Nr467partcvol02 Si

Marine Division92571 Neuilly-sur-Seine Cedex- France

Tel: + 33 (0)1 55 24 70 00 - Fax: + 33 (0)1 55 24 70 25Marine Website: http://www.veristar.comEmail: [email protected]

© 2011 Bureau Veritas - All rights reserved

PART C – Machinery, Electricity, Automationand Fire Protection

Chapters 2 – 3

NR 467.C2 DT R05 E July 2011

Rules for the Classification ofSteel Ships

ARTICLE 1

1.1. - BUREAU VERITAS is a Society the purpose of whose Marine Division (the "Society") is the classi-fication (" Classification ") of any ship or vessel or structure of any type or part of it or system therein col-lectively hereinafter referred to as a "Unit" whether linked to shore, river bed or sea bed or not, whetheroperated or located at sea or in inland waters or partly on land, including submarines, hovercrafts, drillingrigs, offshore installations of any type and of any purpose, their related and ancillary equipment, subseaor not, such as well head and pipelines, mooring legs and mooring points or otherwise as decided by theSociety.

The Society:• prepares and publishes Rules for classification, Guidance Notes and other documents (“Rules”);• issues Certificates, Attestations and Reports following its interventions (“Certificates”);• publishes Registers.

1.2. - The Society also participates in the application of National and International Regulations or Stand-ards, in particular by delegation from different Governments. Those activities are hereafter collectively re-ferred to as " Certification ".1.3. - The Society can also provide services related to Classification and Certification such as ship andcompany safety management certification; ship and port security certification, training activities; all activi-ties and duties incidental thereto such as documentation on any supporting means, software, instrumen-tation, measurements, tests and trials on board.

1.4. - The interventions mentioned in 1.1., 1.2. and 1.3. are referred to as " Services ". The party and/or itsrepresentative requesting the services is hereinafter referred to as the " Client ". The Services are pre-pared and carried out on the assumption that the Clients are aware of the International Maritimeand/or Offshore Industry (the "Industry") practices.1.5. - The Society is neither and may not be considered as an Underwriter, Broker in ship's sale or char-tering, Expert in Unit's valuation, Consulting Engineer, Controller, Naval Architect, Manufacturer, Ship-builder, Repair yard, Charterer or Shipowner who are not relieved of any of their expressed or impliedobligations by the interventions of the Society.

ARTICLE 22.1. - Classification is the appraisement given by the Society for its Client, at a certain date, following sur-veys by its Surveyors along the lines specified in Articles 3 and 4 hereafter on the level of compliance ofa Unit to its Rules or part of them. This appraisement is represented by a class entered on the Certificatesand periodically transcribed in the Society's Register.

2.2. - Certification is carried out by the Society along the same lines as set out in Articles 3 and 4 hereafterand with reference to the applicable National and International Regulations or Standards.

2.3. - It is incumbent upon the Client to maintain the condition of the Unit after surveys, to presentthe Unit for surveys and to inform the Society without delay of circumstances which may affect thegiven appraisement or cause to modify its scope.2.4. - The Client is to give to the Society all access and information necessary for the safe and efficientperformance of the requested Services. The Client is the sole responsible for the conditions of presenta-tion of the Unit for tests, trials and surveys and the conditions under which tests and trials are carried out.

ARTICLE 33.1. - The Rules, procedures and instructions of the Society take into account at the date of theirpreparation the state of currently available and proven technical knowledge of the Industry. Theyare not a standard or a code of construction neither a guide for maintenance, a safety handbookor a guide of professional practices, all of which are assumed to be known in detail and carefullyfollowed at all times by the Client.Committees consisting of personalities from the Industry contribute to the development of those docu-ments.3.2. - The Society only is qualified to apply its Rules and to interpret them. Any reference to themhas no effect unless it involves the Society's intervention.3.3. - The Services of the Society are carried out by professional Surveyors according to the applicableRules and to the Code of Ethics of the Society. Surveyors have authority to decide locally on matters re-lated to classification and certification of the Units, unless the Rules provide otherwise.

3.4. - The operations of the Society in providing its Services are exclusively conducted by way ofrandom inspections and do not in any circumstances involve monitoring or exhaustive verifica-tion.

ARTICLE 4

4.1. - The Society, acting by reference to its Rules:• reviews the construction arrangements of the Units as shown on the documents presented by the Cli-

ent;• conducts surveys at the place of their construction;• classes Units and enters their class in its Register;• surveys periodically the Units in service to note that the requirements for the maintenance of class are

met.

The Client is to inform the Society without delay of circumstances which may cause the date or theextent of the surveys to be changed.

ARTICLE 55.1. - The Society acts as a provider of services. This cannot be construed as an obligation bearingon the Society to obtain a result or as a warranty.5.2. - The certificates issued by the Society pursuant to 5.1. here above are a statement on the levelof compliance of the Unit to its Rules or to the documents of reference for the Services providedfor.In particular, the Society does not engage in any work relating to the design, building, productionor repair checks, neither in the operation of the Units or in their trade, neither in any advisory serv-ices, and cannot be held liable on those accounts. Its certificates cannot be construed as an im-plied or express warranty of safety, fitness for the purpose, seaworthiness of the Unit or of its valuefor sale, insurance or chartering.5.3. - The Society does not declare the acceptance or commissioning of a Unit, nor of its construc-tion in conformity with its design, that being the exclusive responsibility of its owner or builder,respectively.

5.4. - The Services of the Society cannot create any obligation bearing on the Society or constitute anywarranty of proper operation, beyond any representation set forth in the Rules, of any Unit, equipment ormachinery, computer software of any sort or other comparable concepts that has been subject to any sur-vey by the Society.

ARTICLE 66.1. - The Society accepts no responsibility for the use of information related to its Services which was notprovided for the purpose by the Society or with its assistance.

6.2. - If the Services of the Society cause to the Client a damage which is proved to be the directand reasonably foreseeable consequence of an error or omission of the Society, its liability to-wards the Client is limited to ten times the amount of fee paid for the Service having caused thedamage, provided however that this limit shall be subject to a minimum of eight thousand (8,000)Euro, and to a maximum which is the greater of eight hundred thousand (800,000) Euro and oneand a half times the above mentioned fee.The Society bears no liability for indirect or consequential loss such as e.g. loss of revenue, lossof profit, loss of production, loss relative to other contracts and indemnities for termination of oth-er agreements.6.3. - All claims are to be presented to the Society in writing within three months of the date when the Serv-ices were supplied or (if later) the date when the events which are relied on of were first known to the Client,and any claim which is not so presented shall be deemed waived and absolutely barred. Time is to be in-terrupted thereafter with the same periodicity.

ARTICLE 77.1. - Requests for Services are to be in writing.

7.2. - Either the Client or the Society can terminate as of right the requested Services after givingthe other party thirty days' written notice, for convenience, and without prejudice to the provisionsin Article 8 hereunder. 7.3. - The class granted to the concerned Units and the previously issued certificates remain valid until thedate of effect of the notice issued according to 7.2. here above subject to compliance with 2.3. here aboveand Article 8 hereunder.

7.4. - The contract for classification and/or certification of a Unit cannot be transferred neither assigned.

ARTICLE 88.1. - The Services of the Society, whether completed or not, involve, for the part carried out, the paymentof fee upon receipt of the invoice and the reimbursement of the expenses incurred.

8.2. Overdue amounts are increased as of right by interest in accordance with the applicable leg-islation.8.3. - The class of a Unit may be suspended in the event of non-payment of fee after a first unfruitfulnotification to pay.

ARTICLE 9

9.1. - The documents and data provided to or prepared by the Society for its Services, and the informationavailable to the Society, are treated as confidential. However:• clients have access to the data they have provided to the Society and, during the period of classifica-

tion of the Unit for them, to the classification file consisting of survey reports and certificates whichhave been prepared at any time by the Society for the classification of the Unit;

• copy of the documents made available for the classification of the Unit and of available survey reportscan be handed over to another Classification Society, where appropriate, in case of the Unit's transferof class;

• the data relative to the evolution of the Register, to the class suspension and to the survey status of theUnits, as well as general technical information related to hull and equipment damages, are passed onto IACS (International Association of Classification Societies) according to the association workingrules;

• the certificates, documents and information relative to the Units classed with the Society may bereviewed during certificating bodies audits and are disclosed upon order of the concerned governmen-tal or inter-governmental authorities or of a Court having jurisdiction.

The documents and data are subject to a file management plan.

ARTICLE 1010.1. - Any delay or shortcoming in the performance of its Services by the Society arising from an eventnot reasonably foreseeable by or beyond the control of the Society shall be deemed not to be a breach ofcontract.

ARTICLE 1111.1. - In case of diverging opinions during surveys between the Client and the Society's surveyor, the So-ciety may designate another of its surveyors at the request of the Client.

11.2. - Disagreements of a technical nature between the Client and the Society can be submitted by theSociety to the advice of its Marine Advisory Committee.

ARTICLE 1212.1. - Disputes over the Services carried out by delegation of Governments are assessed within theframework of the applicable agreements with the States, international Conventions and national rules.

12.2. - Disputes arising out of the payment of the Society's invoices by the Client are submitted to the Courtof Nanterre, France.

12.3. - Other disputes over the present General Conditions or over the Services of the Society areexclusively submitted to arbitration, by three arbitrators, in London according to the ArbitrationAct 1996 or any statutory modification or re-enactment thereof. The contract between the Societyand the Client shall be governed by English law.

ARTICLE 1313.1. - These General Conditions constitute the sole contractual obligations binding together theSociety and the Client, to the exclusion of all other representation, statements, terms, conditionswhether express or implied. They may be varied in writing by mutual agreement.13.2. - The invalidity of one or more stipulations of the present General Conditions does not affect the va-lidity of the remaining provisions.

13.3. - The definitions herein take precedence over any definitions serving the same purpose which mayappear in other documents issued by the Society.

BV Mod. Ad. ME 545 k - 17 December 2008

MARINE DIVISION

GENERAL CONDITIONS

RULES FOR THE CLASSIFICATION OF SHIPS

Part CMachinery, Electricity, Automation and

Fire Protection

Chapters 1 2 3 4

Chapter 1 MACHINERY

Chapter 2 ELECTRICAL INSTALLATIONS

Chapter 3 AUTOMATION

Chapter 4 FIRE PROTECTION, DETECTION AND EXTINCTION

July 2011

The English wording of these rules take precedence over editions in other languages.

Unless otherwise specified, these rules apply to ships for which contracts aresigned after July 1st, 2011. The Society may refer to the contents hereofbefore July 1st, 2011, as and when deemed necessary or appropriate.

2 Bureau Veritas July 2011

CHAPTER 2ELECTRICAL INSTALLATIONS

Section 1 General

1 Application 19

1.1 General1.2 References to other regulations and standards

2 Documentation to be submitted 19

2.1

3 Definitions 19

3.1 General3.2 Essential services3.3 Primary essential services3.4 Secondary essential services3.5 Safety voltage3.6 Low-voltage systems3.7 High-voltage systems3.8 Basic insulation3.9 Supplementary insulation3.10 Double insulation3.11 Reinforced insulation3.12 Earthing3.13 Normal operational and habitable condition3.14 Emergency condition3.15 Main source of electrical power3.16 Dead ship condition3.17 Main generating station3.18 Main switchboard3.19 Emergency switchboard3.20 Emergency source of electrical power3.21 Section boards3.22 Distribution board3.23 Final sub-circuit3.24 Hazardous areas3.25 High fire risk areas3.26 Certified safe-type equipment3.27 Environmental categories3.28 Black out situation

Section 2 General Design Requirements

1 Environmental conditions 24

1.1 General1.2 Ambient air temperatures1.3 Humidity1.4 Sea water temperatures1.5 Salt mist1.6 Inclinations1.7 Vibrations

July 2011 Bureau Veritas 3

2 Quality of power supply 24

2.1 General2.2 a.c. distribution systems2.3 d.c. distribution systems2.4 Harmonic distortions

3 Electromagnetic susceptibility 26

3.1

4 Materials 26

4.1 General4.2 Insulating materials for windings4.3 Insulating materials for cables

5 Construction 26

5.1 General5.2 Degree of protection of enclosures

6 Protection against explosion hazard 27

6.1 Protection against explosive gas or vapour atmosphere hazard6.2 Protection against combustible dust hazard

Section 3 System Design

1 Supply systems and characteristics of the supply 28

1.1 Supply systems1.2 Maximum voltages

2 Sources of electrical power 28

2.1 General2.2 Main source of electrical power2.3 Emergency source of electrical power2.4 Use of emergency generator in port

3 Distribution 33

3.1 Earthed distribution systems3.2 Insulated distribution systems3.3 Distribution systems with hull return3.4 General requirements for distribution systems3.5 Main distribution of electrical power3.6 Emergency distribution of electrical power3.7 Shore supply3.8 Supply of motors3.9 Specific requirements for special power services3.10 Power supply to heaters3.11 Refeer containers3.12 Power supply to final sub-circuits: socket outlet and lighting3.13 Navigation lights3.14 General emergency alarm system3.15 Public address system3.16 Combined general emergency alarm-public address system3.17 Control and indication circuits3.18 Power supply to the speed control systems of main propulsion engines3.19 Power supply to the speed control systems of generator sets3.20 Installation of water-based local application fire-fighting systems (FWBLAFFS)


4 Degrees of protection of the enclosures 38

4.1 General4.2 Installation of electrical and electronic equipment in engine rooms protected by

fixed water-based local application fire-fighting systems (FWBLAFFS)

5 Diversity (demand) factors 40

5.1 General

6 Environmental categories of the equipment 40

6.1 Environmental categories

7 Electrical protection 40

7.1 General requirements for overcurrent protection7.2 Short-circuit currents7.3 Selection of equipment7.4 Protection against short-circuit7.5 Continuity of supply and continuity of service7.6 Protection against overload7.7 Localisation of overcurrent protection7.8 Protection of generators7.9 Protection of circuits7.10 Protection of motors7.11 Protection of storage batteries7.12 Protection of shore power connection7.13 Protection of measuring instruments, pilot lamps and control circuits7.14 Protection of transformers

8 System components 44

8.1 General

9 Electrical cables 45

9.1 General9.2 Choice of insulation9.3 Choice of protective covering9.4 Cables in refrigerated spaces9.5 Cables in areas with a risk of explosion9.6 Cables in circuits required to be operable under fire condition9.7 Cables for submerged bilge pumps9.8 Internal wiring of switchboards and other enclosures for equipment9.9 Current carrying capacity of cables9.10 Minimum nominal cross-sectional area of conductors9.11 Choice of cables

10 Electrical installations in hazardous areas 50

10.1 Electrical equipment10.2 Electrical cables10.3 Electrical installations in battery rooms10.4 Electrical installations in paint stores or enclosed spaces leading to paint stores10.5 Electrical installations in stores for welding gas (acetylene) bottles10.6 Special ships


Section 4 Rotating Machines

1 Constructional and operational requirements for generators and motors 53

1.1 Mechanical construction1.2 Sliprings, commutators and brushes1.3 Terminal connectors1.4 Electrical insulation

2 Special requirements for generators 53

2.1 Prime movers, speed governors and overspeed protection2.2 A.c. generators

3 Testing of rotating machines 54

3.1 General3.2 Shaft material3.3 Tests

4 Description of test 55

4.1 Technical documentation and visual inspection4.2 Insulation resistance measurement4.3 Winding resistance measurement4.4 Verification of the voltage regulation4.5 Rated load test and temperature rise measurements4.6 Overload/ overcurrent test4.7 Verification of the steady short circuit current4.8 Overspeed test4.9 Dielectric strength test4.10 No load test4.11 Verification of degree of protection4.12 Verification of bearings

5 Additional tests for rotating machines used as propulsion motor or thruster 57

5.1 General

Section 5 Transformers

1 Constructional and operational requirements 58

1.1 Construction1.2 Terminals1.3 Voltage variation, short-circuit conditions and parallel operation1.4 Electrical insulation and temperature rise1.5 Insulation tests

2 Testing 59

2.1 General2.2 Tests on transformers


Section 6 Semiconductor Convertors

1 Constructional and operational requirements 60

1.1 Construction1.2 Protection1.3 Parallel operation with other power sources1.4 Temperature rise1.5 Insulation test

2 Requirements for uninterruptible power system (UPS) units as alternative and/or transitional power 61

2.1 Definitions2.2 Design and construction2.3 Location2.4 Performance

3 Testing 61

3.1 General3.2 Tests on convertors3.3 Additional testing and survey for uninterruptible power system (UPS) units

as alternative and/or transitional power

Section 7 Storage Batteries and Chargers

1 Constructional requirements for batteries 63

1.1 General1.2 Vented batteries1.3 Valve-regulated sealed batteries1.4 Tests on batteries1.5 Battery maintenance

2 Constructional requirements for chargers 63

2.1 Characteristics2.2 Tests on chargers

Section 8 Switchgear and Controlgear Assemblies

1 Constructional requirements for main and emergency switchboards 65

1.1 Construction1.2 Busbars and bare conductors1.3 Internal wiring1.4 Switchgear and controlgear1.5 Auxiliary circuits1.6 Instruments

2 Constructional requirements for section boards and distribution boards 67

2.1 Construction

3 Testing 67

3.1 General3.2 Inspection of equipment, check of wiring and electrical operation test3.3 High voltage test3.4 Measurement of insulation resistance


Section 9 Cables

1 Constructional requirements 69

1.1 Construction1.2 Conductors1.3 Insulating materials1.4 Inner covering, fillers and binders1.5 Protective coverings (armour and sheath)1.6 Identification

2 Testing 70

2.1 Type tests2.2 Routine tests

Section 10 Miscellaneous Equipment

1 Switchgear and controlgear, protective devices 71

1.1 General1.2 Circuit-breakers1.3 Protection devices

2 Lighting fittings 71

2.1 Applicable requirements2.2 Construction

3 Accessories 71

3.1 Applicable requirements3.2 Construction

4 Plug-and-socket connections 72

4.1 Applicable requirements

5 Heating and cooking appliances 72

5.1 Applicable requirements5.2 General5.3 Space heaters5.4 Cooking appliances5.5 Fuel oil and lube oil heaters5.6 Water heaters

Section 11 Location

1 General 73

1.1 Location1.2 Areas with a risk of explosion

2 Main electrical system 73

2.1 Location in relation to the emergency system2.2 Main switchboard


3 Emergency electrical system 73

3.1 Spaces for the emergency source3.2 Location in relation to the main electrical system3.3 Emergency switchboard3.4 Emergency battery

4 Distribution boards 74

4.1 Distribution boards for cargo spaces and similar spaces4.2 Distribution board for navigation lights

5 Cable runs 74

5.1 General5.2 Location of cables in relation to the risk of fire and overheating5.3 Location of cables in relation to electromagnetic interference5.4 Services with a duplicate feeder5.5 Emergency circuits5.6 Electrical distribution in passenger ships

6 Storage batteries 75

6.1 General6.2 Large vented batteries6.3 Moderate vented batteries6.4 Small vented batteries6.5 Ventilation

Section 12 Installation

1 General 77

1.1 Protection against injury or damage caused by electrical equipment1.2 Protection against damage to electrical equipment1.3 Accessibility1.4 Electrical equipment in environmentally controlled spaces

2 Earthing of non-current carrying parts 77

2.1 Parts which are to be earthed2.2 Methods of earthing2.3 Earthing connections2.4 Connection to the ship’s structure2.5 Earthed distribution systems2.6 Aluminium superstructures

3 Rotating machines 79

3.1

4 Semiconductor convertors 79

4.1 Semiconductor power convertors

5 Vented type storage batteries 79

5.1 General5.2 Protection against corrosion

6 Switchgear and controlgear assemblies 79

6.1 Main switchboard6.2 Emergency switchboard6.3 Section boards and distribution boards


7 Cables 80

7.1 General7.2 Radius of bend7.3 Fixing of cables7.4 Mechanical protection7.5 Penetrations of bulkheads and decks7.6 Expansion joints7.7 Cables in closed pipes or conduits7.8 Cables in casings or trunking and conduits with removable covers7.9 Cable ends7.10 Joints and tappings (branch circuit)7.11 Earthing and continuity of metal coverings of cables7.12 Earthing and continuity of metal pipes, conduits and trunking or casings7.13 Precautions for single-core cables for a.c.7.14 Cables in refrigerated spaces7.15 Cables in areas with a risk of explosion7.16 Cables and apparatus for services required to be operable under fire conditions7.17 Cables in the vicinity of radio equipment7.18 Cables for submerged bilge pumps7.19 Cable trays/protective casings made of plastics materials

8 Various appliances 85

8.1 Lighting fittings8.2 Heating appliances8.3 Heating cables and tapes or other heating elements

Section 13 High Voltage Installations

1 General 87

1.1 Field of application1.2 Nominal system voltage1.3 High-voltage, low-voltage segregation

2 System design 87

2.1 Distribution2.2 Degrees of protection2.3 Insulation2.4 Protection

3 Rotating machinery 88

3.1 Stator windings of generators3.2 Temperature detectors3.3 Tests

4 Power transformers 88

4.1 General

5 Cables 89

5.1 General

6 Switchgear and controlgear assemblies 89

6.1 General6.2 Construction6.3 Auxiliary systems6.4 High voltage test


7 Installation 89

7.1 Electrical equipment7.2 Cables

Section 14 Electric Propulsion Plant

1 General 91

1.1 Applicable requirements1.2 Operating conditions

2 Design of the propulsion plant 91

2.1 General2.2 Power supply2.3 Auxiliary machinery2.4 Electrical Protection2.5 Excitation of electric propulsion motor

3 Construction of rotating machines and semiconductor convertors 92

3.1 Ventilation3.2 Protection against moisture and condensate3.3 Rotating machines3.4 Semiconductor convertors

4 Control and monitoring 93

4.1 General4.2 Power plant control systems4.3 Indicating instruments4.4 Alarm system4.5 Reduction of power

5 Installation 94

5.1 Ventilation of spaces5.2 Cable runs

6 Tests 94

6.1 Test of rotating machines

7 Specific requirements for PODs 95

7.1 General7.2 Rotating commutator7.3 Electric motor 7.4 Instrumentation and associated devices7.5 Additional tests and tests on board

Section 15 Testing

1 General 96

1.1 Rule application1.2 Insulation-testing instruments

2 Type approved components 96

2.1


3 Insulation resistance 96

3.1 Lighting and power circuits3.2 Internal communication circuits3.3 Switchboards3.4 Generators and motors

4 Earth 96

4.1 Electrical constructions4.2 Metal-sheathed cables, metal pipes or conduits

5 Operational tests 97

5.1 Generating sets and their protective devices5.2 Switchgear5.3 Consuming devices5.4 Communication systems5.5 Installations in areas with a risk of explosion5.6 Voltage drop

Appendix 1 Indirect Test Method for Synchronous Machines

1 General 98

1.1 Test method


CHAPTER 3AUTOMATION

Section 1 General Requirements

1 General 103

1.1 Field of application1.2 Regulations and standards1.3 Definitions1.4 General

2 Documentation 104

2.1 General2.2 Documents to be submitted2.3 Documents for computer based system2.4 Documents for type approval of equipment

3 Environmental and supply conditions 105

3.1 General3.2 Power supply conditions

4 Materials and construction 106

4.1 General4.2 Type approved components

5 Alterations and additions 106

5.1

Section 2 Design Requirements

1 General 107

1.1

2 Power supply of automation systems 107

2.1

3 Control systems 107

3.1 General3.2 Local control3.3 Remote control systems3.4 Automatic control systems

4 Control of propulsion machinery 108

4.1 Remote control 4.2 Remote control from navigating bridge4.3 Automatic control 4.4 Automatic control of propulsion and manoeuvring units 4.5 Clutches4.6 Brakes

5 Communications 109

5.1 Communications between navigating bridge and machinery space5.2 Engineers’ alarm


6 Remote control of valves 109

6.1

7 Alarm system 110

7.1 General requirements7.2 Alarm functions

8 Safety system 110

8.1 Design8.2 Function8.3 Shutdown8.4 Standby systems8.5 Testing

Section 3 Computer Based Systems

1 General requirements 112

1.1 General1.2 System type approval1.3 System operation1.4 System reliability1.5 System failure 1.6 System redundancy

2 Hardware 112

2.1 General2.2 Housing

3 Software 112

3.1 General3.2 Software development quality

4 Data transmission link 113

4.1 General4.2 Hardware support4.3 Transmission software4.4 Transmission operation4.5 Redundant network

5 Man-machine interface 113

5.1 General5.2 System functional indication5.3 Input devices5.4 Output devices5.5 Workstations5.6 Computer dialogue

6 Integrated systems 114

6.1 General

7 Expert system 114

7.1

8 System testing 115

8.1


9 System maintenance 115

9.1 Maintenance

Section 4 Constructional Requirements

1 General 116

1.1 General1.2 Materials1.3 Component design1.4 Environmental and supply conditions

2 Electrical and/or electronic systems 116

2.1 General2.2 Electronic system2.3 Electrical system

3 Pneumatic systems 117

3.1

4 Hydraulic systems 117

4.1

5 Automation consoles 117

5.1 General5.2 Indicating instruments5.3 VDU’s and keyboards

Section 5 Installation Requirements

1 General 118

1.1

2 Sensors and components 118

2.1 General2.2 Temperature elements2.3 Pressure elements2.4 Level switches

3 Cables 118

3.1 Installation3.2 Cable terminations

4 Pipes 119

4.1

5 Automation consoles 119

5.1 General

Section 6 Testing

1 General 120

1.1 General


2 Type approval 120

2.1 General2.2 Hardware type approval2.3 Software type approval2.4 Navigational and radio equipment2.5 Loading instruments 2.6 Oil mist detection system

3 Acceptance testing 126

3.1 General3.2 Hardware testing3.3 Software testing

4 On board tests 126

4.1 General

Appendix 1 Type Testing Procedure for Crankcase Oil Mist Detection and Alarm Equipment

1 General 128

1.1 Scope1.2 Recognised standard1.3 Purpose1.4 Test facilities

2 Testing 128

2.1 Equipment testing2.2 Functional tests2.3 Detectors and alarm equipment to be tested2.4 Method2.5 Assessment2.6 Design series qualification2.7 Test report2.8 Acceptance



Fire Protection

Chapter 2

ELECTRICAL INSTALLATIONS

SECTION 1 GENERAL

SECTION 2 GENERAL DESIGN REQUIREMENTS

SECTION 3 SYSTEM DESIGN

SECTION 4 ROTATING MACHINES

SECTION 5 TRANSFORMERS

SECTION 6 SEMICONDUCTOR CONVERTORS

SECTION 7 STORAGE BATTERIES AND CHARGERS

SECTION 8 SWITCHGEAR AND CONTROLGEAR ASSEMBLIES

SECTION 9 CABLES

SECTION 10 MISCELLANEOUS EQUIPMENT

SECTION 11 LOCATION

SECTION 12 INSTALLATION

SECTION 13 HIGH VOLTAGE INSTALLATIONS

SECTION 14 ELECTRIC PROPULSION PLANT

SECTION 15 TESTING

APPENDIX 1 INDIRECT TEST METHOD FOR SYNCHRONOUS MACHINES



Pt C, Ch 2, Sec 1

SECTION 1 GENERAL

1 Application

1.1 General

1.1.1 The requirements of this Chapter apply to electricalinstallations on ships. In particular, they apply to the com-ponents of electrical installations for:• primary essential services• secondary essential services• essential services for special purposes connected with

ships specifically intended for such purposes (e.g. cargopumps on tankers, cargo refrigerating systems, air con-ditioning systems on passenger ships)

• services for habitability.

The other parts of the installation are to be so designed as notto introduce any risks or malfunctions to the above services.

1.1.2 The Society may consider modified requirements forinstallations not exceeding either 50 V or 50 kW total genera-tor capacity (and for ships classed for “restricted navigation”).

1.2 References to other regulations and standards

1.2.1 The Society may refer to other regulations and stan-dards when deemed necessary. These include the IEC publi-cations, notably the IEC 60092 series.

1.2.2 When referred to by the Society, publications by theInternational Electrotechnical Commission (IEC) or otherinternationally recognised standards, are those currently inforce at the date of agreement for ship classification.

2 Documentation to be submitted

2.1

2.1.1 The documents listed in Tab 1 are to be submitted.The list of documents requested is to be intended as guid-ance for the complete set of information to be submitted,rather than an actual list of titles.

The Society reserves the right to request the submission ofadditional documents in the case of non-conventionaldesign or if it is deemed necessary for the evaluation of thesystem, equipment or components.

Unless otherwise agreed with the Society, documents forapproval are to be sent in triplicate if submitted by the Ship-yard and in four copies if submitted by the equipment supplier.

Documents requested for information are to be sent induplicate.

In any case, the Society reserves the right to require addi-tional copies when deemed necessary.

3 Definitions

3.1 General

3.1.1 Unless otherwise stated, the terms used in this Chap-ter have the definitions laid down by the IEC standards.

The definitions given in the following requirements alsoapply.

3.2 Essential services

3.2.1 Essential services are defined in Pt A, Ch 1, Sec 1,[1.2.1]. They are subdivided in primary and secondaryessential services.

3.3 Primary essential services

3.3.1 Primary essential services are those which need to bemaintained in continuous operation.

Examples of equipment for primary essential services arethe following:

• steering gear

• actuating systems of controllable pitch propellers

• scavenging air blowers, fuel oil supply pumps, fuelvalve cooling pumps, lubricating oil pumps and coolingwater pumps for main and auxiliary engines and tur-bines necessary for the propulsion

• forced draught fans, feed water pumps, water circulatingpumps, condensate pumps, oil burning installations, forsteam plants or steam turbines ship, and also for auxil-iary boilers on ship where steam is used for equipmentsupplying primary essential services

• azimuth thrusters which are the sole means for propul-sion/steering with lubricating oil pumps, cooling waterpumps

• electrical equipment for electric propulsion plant withlubricating oil pumps and cooling water pumps

• electric generators and associated power sources sup-plying the above equipment

• hydraulic pumps supplying the above equipment

• viscosity control equipment for heavy fuel oil

• control, monitoring and safety devices/systems forequipment for primary essential services

• speed regulators dependent on electrical energy formain or auxiliary engines necessary for propulsion

• starting equipment of diesel engines and gas turbines.

The main lighting system for those parts of the ship nor-mally accessible to and used by personnel and passengersis also considered (included as) a primary essential service.


Pt C, Ch 2, Sec 1

Table 1 : Documents to be submitted

3.4 Secondary essential services

3.4.1 Secondary essential services are those services whichneed not necessarily be in continuous operation.Examples of equipment for secondary essential services arethe following:• windlasses• thrusters• fuel oil transfer pumps and fuel oil treatment equipment

• lubrication oil transfer pumps and lubrication oil treat-ment equipment

• preheaters for heavy fuel oil

• sea water pumps

• starting air and control air compressors

• bilge, ballast and heeling pumps

• fire pumps and other fire-extinguishing medium pumps

• ventilation fans for engine and boiler rooms

N° I/A (1) Documents to be submitted

1 A General arrangement of electrical installation.

2 A Single line diagram of main and emergency power and lighting systems.

3 I Electrical power balance (main and emergency supply).

4 A Calculation of short-circuit currents for each installation in which the sum of rated power of the energy sources which may be connected contemporaneously to the network is greater than 500 kVA (kW).

5 A Where the maximal short-circuit current on the main bus-bar is expected to exceed 50 kA for the main andemergency switchboards, justification of the main bus-bar and bracket strength related to induced electro-magnetic forces (except junction bars to the interrupting and protective devices).

6 A List of circuits including, for each supply and distribution circuit, data concerning the nominal current, the cable type, length and cross-section, nominal and setting values of the protective and control devices.

7 A Single line diagram and detailed diagram of the main switchboard.

8 A Single line diagram and detailed diagram of the emergency switchboard.

9 A Diagram of the most important section boards or motor control centres (above 100 kW).

10 A Diagram of the supply for monitoring and control systems of propulsion motors and generator prime movers.

11 A Diagram of the supply, monitoring and control systems of the rudder propellers.

12 A Diagram of the supply, monitoring and control systems of controllable pitch propellers.

13 A Diagram of the general emergency alarm system, of the public address system and other intercommunicationsystems.

14 A Detailed diagram of the navigation-light switchboard.

15 A Diagram of the remote stop system (ventilation, fuel pump, fuel valves, etc.).

16 A List of batteries including type and manufacturer, voltage and capacity, location and equipment and/or system(s) served, maintenance and replacement schedule (when used for essential and emergency services).

17 A (2) Selectivity and coordination of the electrical protection.

18 A (3) Single line diagram.

19 A (3) Principles of control system and its power supply.

20 A (3) Alarm and monitoring system including:• list of alarms and monitoring points• power supply diagram.

21 A (3) Safety system including:• list of monitored parameters for safety system• power supply diagram.

22 I (3) Arrangements and details of the propulsion control consoles and panels.

23 I (3) Arrangements and details of electrical coupling.

24 I (3) Arrangements and details of the frequency convertors together with the justification of their characteristics.

25 I (3) Arrangements of the cooling system provided for the frequency convertor and motor enclosure.

26 A (3) Test program for convertors and rotating machines having rated power > 3 MW, dock and sea trials.

(1) A : To be submitted for approval I : To be submitted for information.

(2) For high voltage installations.(3) For electric propulsion installations.


Pt C, Ch 2, Sec 1

• services considered necessary to maintain dangerouscargo in a safe condition

• navigation lights, aids and signals

• internal safety communication equipment

• fire detection and alarm systems

• electrical equipment for watertight closing appliances

• electric generators and associated power supplying theabove equipment

• hydraulic pumps supplying the above mentioned equip-ment

• control, monitoring and safety for cargo containmentsystems

• control, monitoring and safety devices/systems forequipment for secondary essential services.

• cooling system of environmentally controlled spaces.

3.4.2 Services for habitability are those intended for mini-mum comfort conditions for people on board.

Examples of equipment for maintaining conditions of habit-ability:

• cooking

• heating

• domestic refrigeration

• mechanical ventilation

• sanitary and fresh water

• electric generators and associated power sources sup-plying the above equipment.

3.5 Safety voltage

3.5.1 A voltage which does not exceed 50 V a.c. r.m.s.between conductors, or between any conductor and earth,in a circuit isolated from the supply by means such as asafety isolating transformer.

3.5.2 A voltage which does not exceed 50 V d.c. betweenconductors or between any conductor and earth in a circuitisolated from higher voltage circuits.

3.6 Low-voltage systems

3.6.1 Alternating current systems with rated voltagesgreater than 50 V r.m.s. up to 1000 V r.m.s. inclusive anddirect current systems with a maximum instantaneous valueof the voltage under rated operating conditions greater than50 V up to 1500 V inclusive.

3.7 High-voltage systems

3.7.1 Alternating current systems with rated voltagesgreater than 1000 V r.m.s. and direct current systems with amaximum instantaneous value of the voltage under ratedoperating conditions greater than 1500 V.

3.8 Basic insulation

3.8.1 Insulation applied to live parts to provide basic pro-tection against electric shock.

Note 1: Basic insulation does not necessarily include insulationused exclusively for functional purposes.

3.9 Supplementary insulation

3.9.1 Independent insulation applied in addition to basicinsulation in order to provide protection against electricshock in the event of a failure of basic insulation.

3.10 Double insulation

3.10.1 Insulation comprising both basic insulation and sup-plementary insulation.

3.11 Reinforced insulation

3.11.1 A single insulation system applied to live parts,which provides a degree of protection against electric shockequivalent to double insulation.

Note 1: The term "insulation system" does not imply that the insula-tion must be one homogeneous piece. It may comprise several lay-ers which cannot be tested singly as supplementary or basicinsulation.

3.12 Earthing

3.12.1 The earth connection to the general mass of the hullof the ship in such a manner as will ensure at all times animmediate discharge of electrical energy without danger.

3.13 Normal operational and habitable condition

3.13.1 A condition under which the ship as a whole, themachinery, services, means and aids ensuring propulsion,ability to steer, safe navigation, fire and flooding safety,internal and external communications and signals, means ofescape, and emergency boat winches, as well as thedesigned comfortable conditions of habitability are in work-ing order and functioning normally.

3.14 Emergency condition

3.14.1 A condition under which any services needed fornormal operational and habitable conditions are not inworking order due to failure of the main source of electricalpower.

3.15 Main source of electrical power

3.15.1 A source intended to supply electrical power to themain switchboard for distribution to all services necessaryfor maintaining the ship in normal operational and habitablecondition.


Pt C, Ch 2, Sec 1

3.16 Dead ship condition

3.16.1 The condition under which the main propulsionplant, boilers and auxiliaries are not in operation due to theabsence of power.

Note 1: Dead ship condition is a condition in which the entiremachinery installation, including the power supply, is out of opera-tion and the auxiliary services such as compressed air, starting cur-rent from batteries etc., for bringing the main propulsion intooperation and for the restoration of the main power supply are notavailable.

3.17 Main generating station

3.17.1 The space in which the main source of electricalpower is situated.

3.18 Main switchboard

3.18.1 A switchboard which is directly supplied by themain source of electrical power and is intended to distributeelectrical energy to the ship’s services.

3.19 Emergency switchboard

3.19.1 A switchboard which in the event of failure of themain electrical power supply system is directly supplied bythe emergency source of electrical power or the transitionalsource of emergency and is intended to distribute electricalenergy to the emergency services.

3.20 Emergency source of electrical power

3.20.1 A source of electrical power, intended to supply theemergency switchboard in the event of failure of the supplyfrom the main source of electrical power.

3.21 Section boards

3.21.1 A switchgear and controlgear assembly which issupplied by another assembly and arranged for the distribu-tion of electrical energy to other section boards or distribu-tion boards.

3.22 Distribution board

3.22.1 A switchgear and controlgear assembly arranged forthe distribution of electrical energy to final sub-circuits.

3.23 Final sub-circuit

3.23.1 That portion of a wiring system extending beyondthe final required overcurrent protective device of a board.

3.24 Hazardous areas

3.24.1 Areas in which an explosive atmosphere is or maybe expected to be present in quantities such as to requirespecial precautions for the construction, installation anduse of electrical apparatus.

Note 1: An explosive gas atmosphere is a mixture with air, underatmospheric conditions, of flammable substances in the form ofgas, vapour or mist, in which, after ignition, combustion spreadsthroughout the unconsumed mixture.

3.24.2 Hazardous areas are classified in zones based uponthe frequency and the duration of the occurrence of explo-sive atmosphere.

3.24.3 Hazardous areas for explosive gas atmosphere areclassified in the following zones:

• Zone 0: an area in which an explosive gas atmosphereis present continuously or is present for long periods

• Zone 1: an area in which an explosive gas atmosphereis likely to occur in normal operation

• Zone 2: an area in which an explosive gas atmosphereis not likely to occur in normal operation and if it doesoccur, is likely to do only infrequently and will exist fora short period only.

3.25 High fire risk areas

3.25.1 The high fire risk areas are defined as follows:

a) machinery spaces as defined in Ch 4, Sec 1, [3.24]

b) spaces containing fuel treatment equipment and otherhighly inflammable substances

c) galleys and pantries containing cooking appliances

d) laundry with drying equipment

e) spaces as defined in Ch 4, Sec 5, [1.3.3] for ships carry-ing more than 36 passengers, as:

• (8) accommodation spaces of greater fire risk

• (12) machinery spaces and main galleys

• (14) other spaces in which flammable liquids arestowed

f) enclosed or semi-enclosed hazardous spaces, in whichcertified safe type electric equipment is required.

3.26 Certified safe-type equipment

3.26.1 Certified safe-type equipment is electrical equip-ment of a type for which a national or other appropriateauthority has carried out the type verifications and testsnecessary to certify the safety of the equipment with regardto explosion hazard when used in an explosive gas atmo-sphere.


Pt C, Ch 2, Sec 1


3.27.1 Electrical equipment is classified into environmentalcategories according to the temperature range, vibrationlevels, and resistance to chemically active substances andto humidity.The designation of the environmental categories is indi-cated by the EC Code in Tab 2.

The first characteristic numeral indicates the temperaturerange in which the electrical equipment operates satisfacto-rily, as specified in Tab 3.

The second characteristic numeral indicates the vibrationlevel in which the electrical equipment operates satisfacto-rily, as specified in Tab 4.

3.27.2 The tests for verifying the additional and supple-mentary letters and the characteristic numeral of the envi-ronmental categories are defined in Ch 3, Sec 6.

3.28 Black out situation

3.28.1 A “blackout situation” means that the main and aux-iliary machinery installations, including the main powersupply, are out of operation but the services for bringingthem into operation (e.g. compressed air, starting currentfrom batteries, etc.) are available.

Table 2 : EC Code

Table 3 : First characteristic numeral

Table 4 : Second characteristic numeral

Code letter First characteristic numeral Second characteristic numeral Additional letter Supplementary letter

EC (numerals 1 to 4) (numerals 1 to 3) (letter S) (1) (letter C) (2)

(1) The additional letter S indicates the resistance to salt mist (exposed decks, masts) of the electrical equipment.(2) The supplementary letter C indicates the relative humidity up to 80% (air conditioned areas) in which the electrical equipment

operates satisfactorily.

First characteristic numeral Brief description of location Temperature range, in °C

1 Air conditioned areas + 5 + 40

2 Enclosed spaces + 5 + 45

3 Inside consoles or close to combustion engines and similar + 5 + 55

4 Exposed decks, masts − 25 + 45

Secondcharacteristic

numeralBrief description of location

Frequency range,in Hz

Displacement amplitude,

in mm

Acceleration amplitude g

1 Machinery spaces, command and control stations, accommodation spaces, exposed decks, cargo spaces

from 2,0 to 13,2 1,0 −

from 13,2 to 100 − 0,7

2 Masts from 2,0 to 13,2 3,0 −

from 13,2 to 50 − 2,1

3 On air compressors, on diesel engines and similar from 2,0 to 25,0 1,6 −

from 25,0 to 100 − 4,0


Pt C, Ch 2, Sec 2

SECTION 2 GENERAL DESIGN REQUIREMENTS

1 Environmental conditions

1.1 General

1.1.1 The electrical components of installations are to bedesigned and constructed to operate satisfactorily under theenvironmental conditions on board.

In particular, the conditions shown in the tables in this Arti-cle are to be taken into account.

Note 1: The environmental conditions are characterised by:

• one set of variables including climatic conditions (e.g. ambientair temperature and humidity), conditions dependent uponchemically active substances (e.g. salt mist) or mechanicallyactive substances (e.g. dust or oil), mechanical conditions (e.g.vibrations or inclinations) and conditions dependent uponelectromagnetic noise and interference, and

• another set of variables dependent mainly upon location onvessels, operational patterns and transient conditions.

1.2 Ambient air temperatures

1.2.1 For ships classed for unrestricted navigation, theambient air temperature ranges shown in Tab 1 are applica-ble in relation to the various locations of installation.

Table 1 : Ambient air temperature

1.2.2 For ships classed for service in specific zones, theSociety may accept different ranges for the ambient air tem-perature (e.g. for ships operating outside the tropical belt,the maximum ambient air temperature may be assumed asequal to + 40°C instead of + 45°C).

1.3 Humidity

1.3.1 For ships classed for unrestricted service, the humid-ity ranges shown in Tab 2 are applicable in relation to thevarious locations of installation.

Table 2 : Humidity

1.4 Sea water temperatures

1.4.1 The temperatures shown in Tab 3 are applicable toships classed for unrestricted service.

Table 3 : Water temperature

1.4.2 For ships classed for service in specific zones, theSociety may accept different values for the sea water tem-perature (e.g. for ships operating outside the tropical belt,the maximum sea water temperature may be assumed asequal to + 25°C instead of + 32°C).

1.5 Salt mist

1.5.1 The applicable salt mist content in the air is to be1mg/m3.

1.6 Inclinations

1.6.1 The inclinations applicable are those shown in Tab 4.The Society may consider deviations from these angles ofinclination taking into consideration the type, size and ser-vice conditions of the ships.

1.7 Vibrations

1.7.1 In relation to the location of the electrical compo-nents, the vibration levels given in Tab 5 are to be assumed.

1.7.2 The natural frequencies of the equipment, their sus-pensions and their supports are to be outside the frequencyranges specified.Where this is not possible using a suitable constructionaltechnique, the equipment vibrations are to be dumped so asto avoid unacceptable amplifications.

2 Quality of power supply

2.1 General

2.1.1 All electrical components supplied from the mainand emergency systems are to be so designed and manufac-tured that they are capable of operating satisfactorily underthe normally occuring variations in voltage and frequencyspecified from [2.2] to [2.4].

2.2 a.c. distribution systems

2.2.1 For alternating current components the voltage andfrequency variations of power supply shown in Tab 6 are tobe assumed.

Location Temperature range, in °C

Enclosed spaces + 5 + 45

Inside consoles or fitted on com-bustion engines and similar

+ 5 + 55

Air conditioned areas + 5 + 40

Exposed decks − 25 + 45

Location Humidity

General 95% at 55°C

Air conditioned areas Different values may be considered on a case by case basis

Coolant Temperature range, in °C

Sea water 0 + 32


Pt C, Ch 2, Sec 2

Table 4 : Inclination of ship

Table 5 : Vibration levels

Table 6 : Voltage and frequency variations ofpower supply in a.c.

2.3 d.c. distribution systems

2.3.1 For direct current components the power supply vari-ations shown in Tab 7 are to be assumed.

Table 7 : Voltage variations in d.c.

2.3.2 For direct current components supplied by electricalbattery the following voltage variations are to be assumed:

• +30% to −25% for components connected to the bat-tery during charging (see [2.3.2], Note 1)

• +20% to −25% for components not connected to thebattery during charging.

Note 1: Different voltage variations as determined by the charg-ing/discharging characteristics, including ripple voltage from thecharging device, may be considered.

2.3.3 Any special system, e.g. electronic circuits, whosefunction cannot operate satisfactorily within the limitsshown in the tables should not be supplied directly from thesystem but by alternative means, e.g. through stabilizedsupply.

2.4 Harmonic distortions

2.4.1 For components intended for systems without sub-stantially static converter loads and supplied by synchro-nous generators, it is assumed that the total voltageharmonic distortion does not exceed 5%, and the singleharmonic does not exceed 3% of the nominal voltage.

Type of machinery, equipment or component

Angles of inclination, in degrees (1)

Athwartship Fore-and-aft

static dynamic (4) static dynamic (5)

Machinery and equipment relative to main electrical power installation 15 22,5 5 7,5

Machinery and equipment relative to the emergency power installation and crew and passenger safety systems of the ship (e.g. emergency source of power, emergency fire pumps, etc.)

22,5 (2) 22,5 (2) 10 10

Switchgear and associated electrical and electronic components and remote control systems (3)

22,5 22,5 10 10

(1) Athwartship and fore-and-aft angles may occur simultaneously in their most unfavourable combination.(2) In the case of gas carriers or chemical tankers, the emergency power supply must also remain operable with the ship flooded to

a final athwartship inclination up to a maximum of 30°.(3) No undesired switching operations or functional changes may occur up to an angle of inclination of 45°.(4) The period of dynamic inclination may be assumed equal to 10 s.(5) The period of dynamic inclination may be assumed equal to 5 s.

LocationFrequency range,

in HzDisplacement

amplitude, in mmAccelerationamplitude g

Machinery spaces, command and control stations, accommodation spaces, exposed decks, cargo spaces

from 2,0 to 13,2 1,0 −

from 13,2 to 100 − 0,7

On air compressors, on diesel engines and similarfrom 2,0 to 25,0 1,6 −

from 25,0 to 100 − 4,0

Mastsfrom 2,0 to 13,2 3,0 −

from 13,2 to 50 − 2,1

ParameterVariations

Continuous Transient

Voltage + 6% − 10% ± 20% (recovery time: 1,5 s)

Frequency ± 5% ± 10% (recovery time: 5 s)

Note 1: For alternating current components supplied by emergency generating sets, different variations may be con-sidered.

Parameters Variations

Voltage tolerance (continuous) ± 10%

Voltage cyclic variation 5%

Voltage ripple (a.c. r.m.s. over steady d.c. voltage)

10%


Pt C, Ch 2, Sec 2

2.4.2 For components intended for systems fed by staticconverters, and/or systems in which the static converterload predominates, it is assumed that:

• the single harmonics do not exceed 5% of the nominalvoltage up to the 15th harmonic of the nominal fre-quency, decreasing to 1% at the 100th harmonic (seeFig 1), and that

• the total harmonic distortion does not exceed 10%.

Figure 1 :

2.4.3 Higher values for the harmonic content (e.g. in elec-tric propulsion plant systems) may be accepted on the basisof correct operation of all electrical devices.

3 Electromagnetic susceptibility

3.1

3.1.1 For electronic type components such as sensors,alarm panels, automatic and remote control equipment,protective devices and speed regulators, the conducted andradiated disturbance levels to be assumed are those given inPart C, Chapter 3.

Note 1: See also IEC Publication 60533 - “Electromagnetic Com-patibility of Electrical and Electronic Installations in Ships and ofMobile and Fixed Offshore Units”.

3.1.2 Electrical and electronic equipment on the bridgeand in the vicinity of the bridge, not required neither byclassification rules nor by International Conventions andliable to cause electromagnetic disturbance, shall be of typewhich fulfil the test requirements of test specification Ch 3,Sec 6, Tab 1, tests 19 and 20.

4 Materials

4.1 General

4.1.1 In general, and unless it is adequately protected, allelectrical equipment is to be constructed of durable, flame-retardant, moisture-resistant materials which are not subjectto deterioration in the atmosphere and at the temperaturesto which they are likely to be exposed. Particular consider-ation is to be given to sea air and oil vapour contamination.

Note 1: The flame-retardant and moisture-resistant characteristicsmay be verified by means of the tests cited in IEC Publication60092-101 or in other recognised standards.

4.1.2 Where the use of incombustible materials or liningwith such materials is required, the incombustibility charac-teristics may be verified by means of the test cited in IECPublication 60092-101 or in other recognised standards.

4.2 Insulating materials for windings

4.2.1 Insulated windings are to be resistant to moisture, seaair and oil vapour unless special precautions are taken toprotect insulants against such agents.

4.2.2 The insulation classes given in Tab 8 may be used inaccordance with IEC Publication 60085.

Table 8 : Insulation Classes

4.3 Insulating materials for cables

4.3.1 See Ch 2, Sec 9, [1.3].

5 Construction

5.1 General

5.1.1 All electrical apparatus is to be so constructed as notto cause injury when handled or touched in the normalmanner.

5.1.2 The design of electrical equipment is to allow acces-sibility to each part that needs inspection or adjustment,also taking into account its arrangement on board.

5.1.3 Enclosures are to be of adequate mechanical strengthand rigidity.

5.1.4 Enclosures for electrical equipment are generally tobe of metal; other materials may be accepted for accesso-ries such as connection boxes, socket-outlets, switches andluminaires. Other exemptions for enclosures or parts ofenclosures not made of metal will be specially consideredby the Society.

5.1.5 Cable entrance are not to impair the degree of pro-tection of the relevant enclosure (see Ch 2, Sec 3, Tab 2).

5.1.6 All nuts and screws used in connection with current-carrying parts and working parts are to be effectivelylocked.

5.1.7 All equipment is generally to be provided with suit-able, fixed terminal connectors in an accessible position forconvenient connection of the external cables.

10

5

1

0,11 3 10 15 100

ν

U Uν

(%)

ClassMaximum continuous operating

temperature, in °C

A 105

E 120

B 130

F 155

H 180


Pt C, Ch 2, Sec 2

5.2 Degree of protection of enclosures

5.2.1 Electrical equipment is to be protected against theingress of foreign bodies and water.

The minimum required degree of protection, in relation tothe place of installation, is generally that specified in Ch 2,Sec 3, Tab 2.

5.2.2 The degrees of protection are to be in accordancewith:

• IEC Publication No. 60529 for equipment in general

• IEC Publication No. 60034-5 for rotating machines.

5.2.3 For cable entries see [4.3.1].

6 Protection against explosion hazard

6.1 Protection against explosive gas or vapour atmosphere hazard

6.1.1 Electrical equipment intended for use in areas whereexplosive gas or vapour atmospheres may occur (e.g. oiltankers, liquefied gas carriers, chemical tankers, etc.), is tobe of a "safe type" suitable for the relevant flammable atmo-sphere and for shipboard use.

6.1.2 The following “certified safe type” equipment is con-sidered:

• intrinsically-safe: Ex(ia) - Ex(ib)

• flameproof: Ex(d)

• increased safety: Ex(e)

• pressurised enclosure: Ex(p)

• encapsulated: Ex(m)

• sand filled: Ex(q)

• special protection: Ex(s) (apparatus not conforming withIEC 60079 may be considered safe by a national orother authorised body for use in potentially explosiveatmospheres. In such cases, the apparatus is identifiedwith the symbol “s”)

• oil-immersed apparatus (only when required by theapplication): Ex(o).

6.1.3 Other equipment complying with types of protectionother than those in [6.1.2] may be considered by the Soci-ety, such as:• simple electrical apparatus and components (e.g. ther-

mocouples, photocells, strain gauges, junction boxes,switching devices), included in intrinsically-safe circuitsnot capable of storing or generating electrical power orenergy in excess of limits stated in the relevant rules

• electrical apparatus specifically designed and certifiedby the appropriate authority for use in Zone 0 or spe-cially tested for Zone 2 (e.g. type “n” protection)

• equipment the type of which ensures the absence ofsparks and arcs and of “hot spots” during its normaloperation

• pressurised equipment• equipment having an enclosure filled with a liquid

dielectric, or encapsulated.

6.2 Protection against combustible dust hazard

6.2.1 Electrical appliances intended for use in areas wherea combustible dust hazard may be present are to bearranged with enclosures having a degree of protection andmaximum surface temperature suitable for the dust towhich they may be exposed.Note 1: Where the characteristics of the dust are unknown, theappliances are to have a degree of protection IP6X. For most dusts amaximum surface temperature of 200°C is considered adequate.


Pt C, Ch 2, Sec 3

SECTION 3 SYSTEM DESIGN

1 Supply systems and characteristics of the supply

1.1 Supply systems

1.1.1 The following distribution systems may be used:

a) on d.c. installations:• two-wire insulated• two-wire with one pole earthed

b) on a.c. installations:• three-phase three-wire with neutral insulated• three-phase three-wire with neutral directly earthed

or earthed through an impedance• three-phase four-wire with neutral directly earthed

or earthed through an impedance• single-phase two-wire insulated• single-phase two-wire with one phase earthed.

1.1.2 Distribution systems other than those listed in [1.1.1]will be considered by the Society on a case by case basis.

1.1.3 The hull return system of distribution is not to be usedfor power, heating or lighting in any ship of 1600 tons grosstonnage and upwards.

1.1.4 The requirement of [1.1.3] does not preclude underconditions approved by the Society the use of:

a) impressed current cathodic protective systems

b) limited and locally earthed systems, or

c) insulation level monitoring devices provided the circu-lation current does not exceed 30 mA under the mostunfavourable conditions.

Note 1: Limited and locally earthed systems such as starting andignition systems of internal combustion engines are accepted pro-vided that any possible resulting current does not flow directlythrough any dangerous spaces.

1.1.5 For the supply systems of ships carrying liquid devel-oping combustible gases or vapours, see Pt D, Ch 7, Sec 5,Pt D, Ch 8, Sec 10 or Pt D, Ch 9, Sec 10.

1.1.6 For the supply systems in HV Installations, see Ch 2,Sec 13.

1.2 Maximum voltages

1.2.1 The maximum voltages for both alternating currentand direct current low-voltage systems of supply for theship’s services are given in Tab 1.

1.2.2 Voltages exceeding those shown will be speciallyconsidered in the case of specific systems.

1.2.3 For high voltage systems, see Ch 2, Sec 13.

2 Sources of electrical power

2.1 General

2.1.1 Electrical installations are to be such that:

a) All electrical auxiliary services necessary for maintainingthe ship in normal operational and habitable conditionsand for the preservation of the cargo will be assuredwithout recourse to the emergency source of electricalpower.

b) Electrical services essential for safety will be assuredunder various emergency conditions.

c) When a.c. generators are involved, attention is to begiven to the starting of squirrel-cage motors connectedto the system, particularly with regard to the effect of themagnitude and duration of the transient voltage changeproduced due to the maximum starting current and thepower factor. The voltage drop due to such starting cur-rent is not to cause any motor already operating to stallor have any adverse effect on other equipment in use.

2.2 Main source of electrical power

2.2.1 A main source of electrical power is to be provided,of sufficient capability to supply all electrical auxiliary ser-vices necessary for maintaining the ship in normal opera-tional and habitable conditions and for the preservation ofthe cargo without recourse to the emergency source of elec-trical power.

2.2.2 For vessels propelled by electrical power and havingtwo or more constant voltage propulsion generating setswhich constitute the source of electrical energy for theship’s auxiliary services, see Ch 2, Sec 14.

2.2.3 The main source of electrical power is to consist of atleast two generating sets.

The capacity of these generating sets is to be such that in theevent of any one generating set being stopped it will still bepossible to supply those services necessary to provide:

a) normal operational conditions of propulsion and safety(see [2.2.4])

b) minimum comfortable conditions of habitability (see Ch2, Sec 1, [3.4.2])

c) preservation of the cargo, i. e. all the equipment whichare needed for refrigerated cargo or operation of anysafety device, such as inert gas generator.

Such capacity is, in addition, to be sufficient to start thelargest motor without causing any other motor to stop orhaving any adverse effect on other equipment in operation.


Pt C, Ch 2, Sec 3

Table 1 : Maximum voltages for various ship services

2.2.4 Those services necessary to provide normal opera-tional conditions of propulsion and safety include primaryand secondary essential services.

For the purpose of calculating the capacity necessary forsuch services, it is essential to consider which of them canbe expected to be in use simultaneously.

For a duplicated service, one being supplied electricallyand the other non-electrically (e.g. driven by the mainengine), the electrical capacity is not included in the abovecalculation.

2.2.5 The services in [2.2.4] do not include:

• thrusters not forming part of the main propulsion(except in manoeuvring conditions)

• cargo handling gear

• cargo pumps

• refrigerators for air conditioning.

2.2.6 Further to the provisions above, the generating setsshall be such as to ensure that with any one generator or itsprimary source of power out of operation, the remaininggenerating sets shall be capable of providing the electricalservices necessary to start the main propulsion plant from a"dead ship" condition.

2.2.7 Where the electrical power is normally supplied bymore than one generator set simultaneously in paralleloperation, provision of protection, including automatic dis-connection of sufficient non-essential services and, if neces-sary, secondary essential services and those provided forhabitability, should be made to ensure that, in case of loss

of any of these generating sets, the remaining ones are keptin operation to permit propulsion and steering and toensure safety.

2.2.8 Where the electrical power is normally supplied byone generator, provision shall be made, upon loss of power,for automatic starting and connecting to the main switch-board of stand-by generator(s) of sufficient capacity withautomatic restarting of the essential auxiliaries, in sequen-tial operation if required. Starting and connection to themain switchboard of the stand-by generator is to be prefera-bly within 30 seconds, but in any case not more than 45seconds after loss of power.

Where prime movers with longer starting time are used, thisstarting and connection time may be exceeded uponapproval from the Society.

2.2.9 Load shedding or other equivalent arrangementsshould be provided to protect the generators required in thepresent Article against sustained overload.

The load shedding should be automatic.

The non-essential services, services for habitability and, ifnecessary, the secondary essential services may be shed inorder to make sure that the connected generator set(s) is/arenot overloaded.

2.2.10 The emergency source of electrical power may beused for the purpose of starting from a "dead ship" condi-tion if its capability either alone or combined with that ofany other source of electrical power is sufficient to provideat the same time those services required to be supplied inaccordance with the provisions of [3.6.3], items a), b), c)and d), or Pt D, Ch 11, Sec 5 for passenger ships.

Use Maximum voltage V

For permanently installed and connected to fixed wiring

Power equipment 1000

Heating equipment (except in accommodation spaces) 500

Cooking equipment 500

Lighting 250

Space heaters in accommodation spaces 250

Control (1), communication (including signal lamps) and instrumentation equipment

250

For permanently installed and connected by flexible cable

Power and heating equipment, where such connection is necessary because of the application (e.g. for moveable cranes or other hoisting gear)

1000

For socket-outlets supplying Portable appliances which are not hand-held during operation(e.g. refrigerated containers) by flexible cables

1000

Portable appliances and other consumers by flexible cables 250

Equipment requiring extra precaution against electric shock where a isolating transformer is used to supply one appliance (2)

250

Equipment requiring extra precaution against electric shock with or without a safety transformer (2)

50

(1) For control equipment which is part of a power and heating installation (e.g. pressure or temperature switches for start/stop motors), the same maximum voltage as allowed for the power and heating equipment may be used provided that all compo-nents are constructed for such voltage. However, the control voltage to external equipment is not to exceed 500 V.

(2) Both conductors in such systems are to be insulated from earth.


Pt C, Ch 2, Sec 3

2.2.11 The arrangement of the ship’s main source of electri-cal power shall be such that essential services can be main-tained regardless of the speed and direction of rotation ofthe main propulsion machinery or shafting.

2.2.12 Generators driven by the propulsion plant (shaftgenerators) which are intended to operate at constant speed(e.g. a system where vessel speed and direction are con-trolled by varying propeller pitch) may be accepted as form-ing part of the main source of electrical power if, in allsailing and manoeuvring conditions including the propellerbeing stopped, the capacity of these generators is sufficientto provide the electrical power to comply with [2.2.3] andall further requirements, especially those of [2.2.6]. Theyare to be not less effective and reliable than the indepen-dent generating sets.

2.2.13 Shaft generator installations which do not complywith the provisions of [2.2.12] may be used as additionalsources of electrical power with respect to the power bal-ance provided that:

a) in the event of a loss of power from the shaft genera-tor(s), e.g. due to a sudden stopping of the propulsionplant, a standby generating set is started automatically

b) the capacity of the standby set is sufficient for the loadsnecessary for propulsion and safety of the vessel

c) the time required to restore these services is not longerthan 45 s.

2.2.14 Where transformers, converters or similar appli-ances constitute an essential part of the electrical supplysystem, the system is to be so arranged as to ensure thesame continuity of supply as stated in this sub-article.

This may be achieved by arranging at least two three-phaseor three single-phase transformers supplied, protected andinstalled as indicated in Fig 1, so that with any one trans-former not in operation, the remaining transformer(s) is (are)sufficient to ensure the supply to the services stated in[2.2.3].

Each transformer required is to be located as a separate unitwith separate enclosure or equivalent, and is to be servedby separate circuits on the primary and secondary sides.Each of the primary and secondary circuits is to be providedwith switchgears and protection devices in each phase.

Suitable interlocks or a warning label are to be provided inorder to prevent maintenance or repair of one single-phasetransformer unless both switchgears are opened on their pri-mary and secondary sides.

2.2.15 For ships intended for operation with periodicallyunattended machinery spaces, see Part E, Chapter 3.

2.2.16 For starting arrangements for main generating sets,see Ch 1, Sec 2, [3.1].

2.2.17 Where single phase transformers are used, only onespare element is required if special precautions are taken torapidly replace the faulty one.

2.2.18 Generators and generator systems, having the shippropulsion machinery as their prime mover but not formingpart of the ship main source of electrical power, may beused whilst the ship is at sea to supply electrical servicesrequired for normal operational and habitable conditionsprovided that:

a) there are sufficient and adequately rated additional gen-erators fitted, which constitute the main source of elec-trical power required by [2.2.1]

Figure 1 :

'P' 'P'RST

RST

Three-phase transformers

enclosure or separation

RST

RST

Single-phase transformers


Pt C, Ch 2, Sec 3

b) arrangements are fitted to automatically start one ormore of the generators, constituting the main source ofelectrical power required by [2.2.1], upon the frequencyvariations exceeding ± 10% of the limits specifiedbelow

c) within the declared operating range of the generatorsand/or generator systems the specified limits for the volt-age variations and the frequency variations in Ch 2, Sec2 can be met

d) the short circuit current of the generator and/or genera-tor system is sufficient to trip the generator/generatorsystem circuit-breaker taking into account the selectivityof the protective devices for the distribution system

e) where considered appropriate, load shedding arrange-ments are to be fitted

f) on ships having remote control of the ship's propulsionmachinery from the navigating bridge, means are pro-vided, or procedures be in place, so as to ensure thatsupplies to essential services are maintained duringmanoeuvring conditions in order to avoid a blackout sit-uation.

2.3 Emergency source of electrical power

2.3.1 A self-contained emergency source of electricalpower shall be provided.

2.3.2 Provided that suitable measures are taken for safe-guarding independent emergency operation under all cir-cumstances, the emergency generator may be used,exceptionally, and for short periods, to supply non-emer-gency circuits.

Exceptionally is understood to mean conditions, while thevessel is at sea, such as:

a) blackout situation

b) dead ship situation

c) routine use for testing

d) short-term parallel operation with the main source ofelectrical power for the purpose of load transfer.

Unless otherwise instructed by the Society, the emergencygenerator may be used during lay time in port for the supplyof the ship mains, provided the requirements of [2.4] arecomplied with.

2.3.3 The electrical power available shall be sufficient tosupply all those services that are essential for safety in anemergency, due regard being paid to such services as mayhave to be operated simultaneously.

2.3.4 The emergency source of electrical power shall becapable, having regard to starting currents and the transi-tory nature of certain loads, of supplying simultaneously atleast the services stated in [3.6.3] for the period specified, ifthey depend upon an electrical source for their operation.

2.3.5 The transitional source of emergency electricalpower, where required, is to be of sufficient capacity to sup-ply at least the services stated in [3.6.7] for half an hour, ifthey depend upon an electrical source for their operation.

2.3.6 An indicator shall be mounted in a suitable place onthe main switchboard or in the machinery control room toindicate when the batteries constituting either the emer-gency source of electrical power or the transitional sourceof emergency electrical power referred to in [2.3.15] and[2.3.16] are being discharged.

2.3.7 If the services which are to be supplied by the transi-tional source receive power from an accumulator battery bymeans of semiconductor convertors, means are to be pro-vided for supplying such services also in the event of failureof the convertor (e.g. providing a bypass feeder or a dupli-cation of convertor).

2.3.8 Where electrical power is necessary to restore propul-sion, the capacity of the emergency source shall be suffi-cient to restore propulsion to the ship in conjunction toother machinery as appropriate, from a dead ship conditionwithin 30 min. after blackout.

For the purpose of this requirement only, the dead ship con-dition and blackout are both understood to mean a condi-tion under which the main propulsion plant, boilers andauxiliaries are not in operation and in restoring the propul-sion, no stored energy for starting the propulsion plant, themain source of electrical power and other essential auxilia-ries is to be assumed available. It is assumed that means areavailable to start the emergency generator at all times.

The emergency generator and other means needed torestore the propulsion are to have a capacity such that thenecessary propulsion starting energy is available within 30minutes of blackout/dead ship condition as defined above.Emergency generator stored starting energy is not to bedirectly used for starting the propulsion plant, the mainsource of electrical power and/or other essential auxiliaries(emergency generator excluded).

For steam ships, the 30 minute time limit given in SOLAScan be interpreted as time from blackout/dead ship condi-tion defined above to light-off the first boiler.

2.3.9 Where the emergency source of power is necessaryto restore the main source of electrical power, provisionsare to be made to allow a manual restart of a main generat-ing set in case of failure of the emergency source.

2.3.10 Provision shall be made for the periodic testing ofthe complete emergency system and shall include the test-ing of automatic starting arrangements, where provided.

2.3.11 For starting arrangements for emergency generatingsets, see Ch 1, Sec 2, [3.1].

2.3.12 The emergency source of electrical power may beeither a generator or an accumulator battery which shallcomply with the requirements of [2.3.13] or [2.3.15],respectively.

2.3.13 Where the emergency source of electrical power is agenerator, it shall be:

a) driven by a suitable prime mover with an independentsupply of fuel, having a flashpoint (closed cup test) ofnot less than 43°C


Pt C, Ch 2, Sec 3

b) started automatically upon failure of the main source ofelectrical power supply to the emergency switchboardunless a transitional source of emergency electricalpower in accordance with c) below is provided wherethe emergency generator is automatically started, it shallbe automatically connected to the emergency switch-board those services referred to in [3.6.7] shall then beconnected automatically to the emergency generator,and

c) provided with a transitional source of emergency electri-cal power as specified in [2.3.16] unless an emergencygenerator is provided capable both of supplying the ser-vices mentioned in that paragraph and of being auto-matically started and supplying the required load asquickly as is safe and practicable subject to a maximumof 45 s.

2.3.14 It is accepted to apply the total consumer load insteps providing that:

• the total load is supplied within 45 seconds since powerfailure on the main switchboard

• the power distribution system is designed such that thedeclared maximum step loading is not exceeded

• the compliance of time delays and loading sequencewith the above is demonstrated at ship’s trials.

2.3.15 Where the emergency source of electrical power isan accumulator battery it shall be capable of:

a) carrying the emergency electrical load without recharg-ing while maintaining the voltage of the battery through-out the discharge period within 12% above or below itsnominal voltage

b) automatically connecting to the emergency switchboardin the event of failure of the main source of electricalpower, and

c) immediately supplying at least those services specifiedin [3.6.7].

2.3.16 The transitional source of emergency electricalpower where required by [2.3.13] item c), shall consist ofan accumulator battery which shall operate withoutrecharging while maintaining the voltage of the batterythroughout the discharge period within 12% above orbelow its nominal voltage and be so arranged as to supplyautomatically in the event of failure of either the main or theemergency source of electrical power for half an hour atleast the services in [3.6.7] if they depend upon an electri-cal source for their operation.

2.3.17 Where the emergency and/or transitional source ofpower is an uninterruptible power system (UPS), it is tocomply with the requirement of Ch 2, Sec 6, [3].

2.3.18 Where the emergency and/or transitional emer-gency loads are supplied from a battery via an electronicconverter or inverter, the maximum permitted d.c. voltagevariations are to be taken as those on the load side of theconverter or inverter.

Where the d.c. is converted into a.c. the maximum varia-tions are not exceed those given in Ch 2, Sec 2, Tab 6.

2.3.19 If the emergency generator is fitted with control,alarm and safety systems based on electronic equipment,these systems are to be so arranged that, when in failure,there is still a possibility to operate the emergency generatormanually.

A failure of the electronic governor is not considered.

2.3.20 For the emergency source of electrical power in pas-senger ships, see Pt D, Ch 11, Sec 5.

2.4 Use of emergency generator in port

2.4.1 To prevent the generator or its prime mover frombecoming overloaded when used in port, arrangements areto be provided to shed sufficient non-emergency loads toensure its continued safe operation.

2.4.2 The prime mover is to be arranged with fuel oil filtersand lubrication oil filters, monitoring equipment and pro-tection devices as requested for the prime mover for mainpower generation and for unattended operation.

2.4.3 The fuel oil supply tank to the prime mover is to beprovided with a low level alarm, arranged at a level ensur-ing sufficient fuel oil capacity for the emergency services forthe period of time as required in [3.6].

2.4.4 The prime mover is to be designed and built for con-tinuous operation and should be subjected to a plannedmaintenance scheme ensuring that it is always availableand capable of fulfilling its role in the event of an emer-gency at sea.

2.4.5 Fire detectors are to be installed in the location wherethe emergency generator set and emergency switchboardare installed.

2.4.6 Means are to be provided to readily change over toemergency operation.

2.4.7 Control, monitoring and supply circuits for the pur-pose of the use of the emergency generator in port are to beso arranged and protected that any electrical fault will notinfluence the operation of the main and emergency ser-vices.

When necessary for safe operation, the emergency switch-board is to be fitted with switches to isolate the circuits.

2.4.8 Instructions are to be provided on board to ensurethat, even when the vessel is underway, all control devices(e.g. valves, switches) are in a correct position for the inde-pendent emergency operation of the emergency generatorset and emergency switchboard.

These instructions are also to contain information on therequired fuel oil tank level, position of harbour/sea modeswitch, if fitted, ventilation openings, etc.


Pt C, Ch 2, Sec 3

3 Distribution

3.1 Earthed distribution systems

3.1.1 System earthing is to be effected by means indepen-dent of any earthing arrangements of the non-current-carry-ing parts.

3.1.2 Means of disconnection are to be fitted in the neutralearthing connection of each generator so that the generatormay be disconnected for maintenance or insulation resis-tance measurements.

3.1.3 Generator neutrals may be connected in common,provided that the third harmonic content of the voltagewave form of each generator does not exceed 5%.

3.1.4 Where a switchboard is split into sections operatedindependently or where there are separate switchboards,neutral earthing is to be provided for each section or foreach switchboard. Means are to be provided to ensure thatthe earth connection is not removed when generators areisolated.

3.1.5 Where for final sub-circuits it is necessary to locallyconnect a pole (or phase) of the sub-circuits to earth afterthe protective devices (e.g. in automation systems or toavoid electromagnetic disturbances), provision (e.g.d.c./d.c. convertors or transformers) is to be made such thatcurrent unbalances do not occur in the individual poles orphases.

3.1.6 For high voltage systems see Ch 2, Sec 13.

3.2 Insulated distribution systems

3.2.1 Every insulated distribution system, whether primaryor secondary (see [3.2.1], Note 1), for power, heating orlighting, shall be provided with a device capable of continu-ously monitoring the insulation level to earth (i.e. the valuesof electrical insulation to earth) and of giving an audibleand visual indication of abnormally low insulation values(see Ch 2, Sec 15).

Note 1: A primary system is one supplied directly by generators.Secondary systems are those supplied by transformers or conver-tors.

3.2.2 For high voltage systems see Ch 2, Sec 13.

3.3 Distribution systems with hull return

3.3.1 Where the hull return system is used, if permitted, allfinal sub-circuits, i.e. all circuits fitted after the last protec-tive device, shall be two-wire.

The hull return is to be achieved by connecting to the hullone of the busbars of the distribution board from which thefinal sub-circuits originate.

3.4 General requirements for distribution systems

3.4.1 The distribution system is to be such that the failure ofany single circuit will not endanger or impair primaryessential services and will not render secondary essentialservices inoperative for longer periods.

3.4.2 No common switchgear (e.g. contactors for emer-gency stop) is to be used between the switchboard’s busbarsand two primary non duplicated essential services.

3.4.3 Where the main source of electrical power is neces-sary for propulsion and steering of the ship, the system shallbe so arranged that the electrical supply to equipment nec-essary for propulsion and steering and to ensure safety ofthe ship will be maintained or immediately restored in thecase of loss of any one of the generators in service.

3.5 Main distribution of electrical power

3.5.1 Where the main source of electrical power is neces-sary for propulsion of the ship, the main busbar is to bedivided into at least two parts which are normally to beconnected by circuit breakers or other approved meanssuch as circuit breakers without tripping mechanisms or dis-connecting links or switches by means of which busbarscan be split safely and easily.

Bolted links, for example bolted bus bar sections, are notaccepted.

The connection of generating sets and associated auxiliariesand other duplicated equipment is to be equally dividedbetween the parts as far as practicable, so that in the eventof damage to one section of the switchboard the remainingparts are still supplied.

3.5.2 Two or more units serving the same consumer (e.g.main and standby lubricating oil pumps) are to be suppliedby individual separate circuits without the use of commonfeeders, protective devices or control circuits.

This requirement is satisfied when such units are suppliedby separate cables from the main switchboard or from twoindependent section boards.

3.5.3 A main electric lighting system which shall provideillumination throughout those parts of the ship normallyaccessible to and used by (passengers or) crew shall be sup-plied from the main source of electrical power.

3.6 Emergency distribution of electrical power

3.6.1 The emergency switchboard shall be supplied duringnormal operation from the main switchboard by an inter-connector feeder which shall be adequately protected atthe main switchboard against overload and short-circuit andwhich is to be disconnected automatically at the emergencyswitchboard upon failure of the main source of electricalpower.

Where the system is arranged for feedback operation, theinterconnector feeder is also to be protected at the emer-gency switchboard at least against short-circuit.


Pt C, Ch 2, Sec 3

3.6.2 In order to ensure ready availability of the emergencysource of electrical power, arrangements shall be madewhere necessary to disconnect automatically non-emer-gency circuits from the emergency switchboard to ensurethat power shall be available to the emergency circuits.

3.6.3 The emergency source of electrical power shall becapable of supplying simultaneously at least the followingservices for the periods specified hereafter, if they dependupon an electrical source for their operation:

a) for a period of 3 hours, emergency lighting at everymuster and embarkation station and over the sides

b) for a period of 18 hours, emergency lighting:

1) in all service and accommodation alleyways, stair-ways and exits, personnel lift cars and personnel lifttrunks

2) in the machinery spaces and main generating sta-tions including their control positions

3) in all control stations, machinery control rooms, andat each main and emergency switchboard

4) at all stowage positions for firemen’s outfits

5) at the steering gear, and

6) at the fire pump referred to in e) below, at the sprin-kler pump, if any, at the emergency bilge pump, ifany, and at the starting positions of their motors

c) for a period of 18 hours:

1) the navigation lights and other lights required by theInternational Regulations for Preventing Collisions atSea in force

2) on ships constructed on or after 1 February 1995 theVHF radio installation required by RegulationIV/7.1.1 and IV/7.1.2 of SOLAS Consolidated Edi-tion 1992, and, if applicable:

• the MF radio installation required by RegulationsIV/9.1.1, IV/9.1.2, IV/10.1.2 and IV/10.1.3

• the ship earth station required by RegulationIV/10.1.1, and

• the MF/HF radio installation required by Regula-tions IV/10.2.1, IV/10.2.2 and IV/11.1

d) for a period of 18 hours:

1) all internal communication equipment as required inan emergency [3.6.4]

2) the shipborne navigational equipment as requiredby Regulation V/19 where such provision is unrea-sonable or impracticable the Society may waive thisrequirement for ships of less than 5 000 tons grosstonnage

3) the fire detection and fire alarm systems, and

4) intermittent operation of the daylight signallinglamp, the ship’s whistle, the manually operated callpoints and all internal signals (see [3.6.5]) that arerequired in an emergency unless such services havean independent supply for the period of 18 hoursfrom an accumulator battery suitably located for usein an emergency

e) for a period of 18 hours: one of the fire pumps requiredby the relevant provisions of Part C, Chapter 4, if depen-dent upon the emergency generator for its source ofpower

f) for the period of time required in Ch 1, Sec 11, [2], thesteering gear where it is required to be so supplied.

3.6.4 Internal communication equipment required in anemergency generally includes:

a) the means of communication between the navigatingbridge and the steering gear compartment

b) the means of communication between the navigatingbridge and the position in the machinery space or con-trol room from which the engines are normally con-trolled

c) the means of communication which is providedbetween the bridge and the radio communication sta-tion, if any

d) the public address system.

3.6.5 Internal signals required in an emergency generallyinclude:

a) general alarm

b) watertight door indication.

3.6.6 In a ship engaged regularly in voyages of short dura-tion, i.e. voyages where the route is no greater than 20 nau-tical miles offshore or where the vessel has a class notation"Coastal Navigation", the Society may, if satisfied that anadequate standard of safety would be attained, accept alesser period than the 18-hour period specified in [3.6.3],items b) to e), but not less than 12 hours.Note 1: In ships for which Solas is not applicable, a reduced periodof time may be accepted.

Note 2: For passenger ships see Pt D, Ch 11, Sec 5.

3.6.7 The transitional source of emergency electricalpower, where required, shall supply for half an hour at leastthe following services if they depend upon an electricalsource for their operation:

a) the lighting required by [3.6.3], items a), b) and c) 1) forthis transitional phase, the required emergency electriclighting, in respect of the machinery space and theaccommodation and service spaces may be provided bypermanently fixed, individual, automatically charged,relay operated accumulator lamps, and

b) all services required by [3.6.3], items d) 1), d) 3) andd) 4), unless such services have an independent supplyfor the period specified from an accumulator batterysuitably located for use in an emergency.

3.7 Shore supply

3.7.1 Where arrangements are made for supplying theelectrical installation from a source on shore or elsewhere,a suitable connection box is to be installed on the ship in aconvenient location to receive the flexible cable from theexternal source.

3.7.2 Permanently fixed cables of adequate rating are to beprovided for connecting the box to the main switchboard.


Pt C, Ch 2, Sec 3

3.7.3 Where necessary for systems with earthed neutrals,the box is to be provided with an earthed terminal for con-nection between the shore’s and ship’s neutrals or for con-nection of a protective conductor.

3.7.4 The connection box is to contain a circuit-breaker ora switch-disconnector and fuses.

The shore connection is to be protected against short-circuitand overload however, the overload protection may beomitted in the connection box if provided on the mainswitchboard.

3.7.5 Means are to be provided for checking the phasesequence of the incoming supply in relation to the ship’ssystem.

3.7.6 The cable connection to the box is to be providedwith at least one switch-disconnector on the main switch-board.

3.7.7 The shore connection is to be provided with an indi-cator at the main switchboard in order to show when thecable is energised.

3.7.8 At the connection box a notice is to be provided giv-ing full information on the nominal voltage and frequencyof the installation.

3.7.9 The switch-disconnector on the main switchboard isto be interlocked with the main generator circuit-breakersin order to prevent its closure when any generator is supply-ing the main switchboard.

3.7.10 Adequate means are to be provided to equalise thepotential between the hull and the shore when the electri-cal installation of the ship is supplied from shore.

3.8 Supply of motors

3.8.1 A separate final sub-circuit is to be provided for everymotor required for an essential service (and for every motorrated at 1 kW or more).

3.8.2 Each motor is to be provided with controlgear ensur-ing its satisfactory starting.

Direct on line starters are accepted if the voltage drop doesnot exceed 15% of the network voltage.

3.8.3 Efficient means are to be provided for the isolation ofthe motor and its associated control gear from all live polesof the supply.

Where the control gear is mounted on or adjacent to aswitchboard, a disconnecting switch in the switchboardmay be used for this purpose.

Otherwise, a disconnecting switch within the control gearenclosure or a separate enclosed disconnecting switch is tobe provided.

3.8.4 Where the starter or any other apparatus for discon-necting the motor is remote from the motor itself, one of thefollowing is to be arranged:

a) provision for locking the circuit disconnecting switch inthe OFF position

b) an additional disconnecting switch fitted near the motor

c) provision such that the fuses in each live pole or phasecan be readily removed and retained by persons autho-rised to have access to the motor.

3.9 Specific requirements for special power services

3.9.1 For the supply and characteristics of the distributionof the following services see the requirements listed:

• steering gear: Ch 1, Sec 11, [2]

• fire-extinguishing and detecting systems: Ch 4, Sec 3and Ch 4, Sec 6

• permanently installed submersible bilge pump: Ch 1,Sec 10, [6.7.7]

• ventilation fans, fuel pumps: Ch 4, Sec 2, [2.1]

• pumps discharging overboard above the lightest waterline and in way of the area of lifeboat and liferaftlaunching: Ch 1, Sec 10, [5.2.4].

3.9.2 All power circuits terminating in a bunker or cargospace are to be provided with a multiple-pole switch out-side the space for disconnecting such circuits.

3.10 Power supply to heaters

3.10.1 Each heater rated more than 16 A is to be connectedto a separate final circuit.

3.11 Refeer containers

3.11.1 Where the ship is intended to carry a large numberof refrigerated containers, provision of suitable means forpreventing earth faults on containers from affecting themain distribution system is to be made (galvanic isolation,tripping of the faulty circuit).

3.12 Power supply to final sub-circuits: socket outlet and lighting

3.12.1 Final sub-circuits for lighting supplying more thanone lighting point and for socket-outlets are to be fitted withprotective devices having a current rating not exceeding16 A.

3.12.2 In spaces such as:

• main and large machinery spaces

• large galleys

• passageways

• stairways leading to boat-decks

• public spaces

there is to be more than one final sub-circuit for lightingsuch that failure of any one circuit does not reduce thelighting to an insufficient level.

3.12.3 Where the emergency installation is required, oneof the circuits in [3.12.2] may be supplied from the emer-gency source of power.


Pt C, Ch 2, Sec 3

3.12.4 All lighting circuits terminating in a bunker or cargospace are to be provided with a multiple-pole switch out-side the space for disconnecting such circuits.

3.12.5 The number of lighting points (lamps) supplied by afinal sub-circuit having a current rating not exceeding 16 Ais not to exceed the following maxima:

• 10 lamps for voltage up to 55 V

• 14 lamps for voltage from 56 V up to 120 V

• 24 lamps for voltage from 121 V to 250 V.

3.12.6 Final sub-circuits for lighting in accommodationspaces may include socket-outlets. In that case, eachsocket-outlet counts for two lighting points.

3.13 Navigation lights

3.13.1 Navigation lights are to be connected separately toa distribution board specially reserved for this purpose.

3.13.2 The distribution board in [3.13] is to be suppliedfrom two alternative circuits, one from the main source ofpower and one from the emergency source of power (seealso [3.6]).

The transfer of supply is to be practicable from the bridge,for example by means of a switch.

3.13.3 Each navigation light is to be controlled and pro-tected in each insulated pole by a double-pole switch and afuse or, alternatively, by a double-pole circuit-breaker, fittedon the distribution board referred to in [3.13].

3.13.4 Where there are double navigation lights, i.e. lightswith two lamps or where for every navigation light a spareis also fitted, the connections to such lights may run in asingle cable provided that means are foreseen in the distri-bution board to ensure that only one lamp or light may besupplied at any one time.

3.13.5 Each navigation light is to be provided with an auto-matic indicator giving audible and/or visual warning in theevent of failure of the light. If an audible device alone is fit-ted, it is to be connected to a separate source of supply fromthat of the navigation lights, for example an accumulator(storage) battery.

If a visual signal is used connected in series with the naviga-tion light, means are to be provided to prevent the extinc-tion of the navigation light due to the failure of the visualsignal.

A minimum level of visibility is to be assured in the case ofuse of dimmer devices.

3.14 General emergency alarm system

3.14.1 An electrically operated bell or klaxon or otherequivalent warning system installed in addition to the ship'swhistle or siren, for sounding the general emergency alarmsignal, is to comply with the requirements of this sub-arti-cle.

3.14.2 The general emergency alarm system is to be sup-plemented by either a public address system complyingwith the requirements in [3.15] or other suitable means ofcommunication.

3.14.3 Entertainment sound system is to be automaticallyturned off when the general alarm system is activated.

3.14.4 The system is to be continuously powered and is tohave an automatic change-over to a standby power supplyin case of loss of normal power supply.An alarm is to be given in the event of failure of the normalpower supply.

3.14.5 The system is to be powered by means of two cir-cuits, one from the ship's main supply and the other fromthe emergency source of electrical power required by [2.3]and [3.6].

3.14.6 The system is to be capable of operation from thenavigation bridge and, except for the ship’s whistle, alsofrom other strategic points.Note 1: Other strategic points are taken to mean those locations,other than the navigation bridge, from where emergency situationsare intended to be controlled and the general alarm system can beactivated. A fire control station or a cargo control station shouldnormally be regarded as strategic points.

3.14.7 The alarm is to continue to function after it has beentriggered until it is manually turned off or is temporarilyinterrupted by a message on the public address system.

3.14.8 The alarm system is to be audible throughout all theaccommodation and normal crew working spaces.

3.14.9 The minimum sound pressure level for the emer-gency alarm tone in interior and exterior spaces is to be 80dB (A) and at least 10 dB (A) above ambient noise levelsoccurring during normal equipment operation with the shipunderway in moderate weather.

3.14.10 In cabins without a loudspeaker installation, anelectronic alarm transducer, e.g. a buzzer or similar, is to beinstalled.

3.14.11 The sound pressure level at the sleeping position incabins and in cabin bathrooms is to be at least 75 dB (A)and at least 10 dB (A) above ambient noise levels.

3.14.12 For cables used for the general emergency alarmsystem, see [9.6.1].

3.15 Public address system

3.15.1 The public address system is to be a loudspeakerinstallation enabling the broadcast of messages into allspaces where people on board are normally present.

In spaces such as under deck passageways, bosun’s locker,hospital and pump rooms, the public address system is/maynot be required.

3.15.2 Where the public address system is used to supple-ment the general emergency alarm system as per [3.14.2], itis to be continuously powered from the emergency sourceof electrical power required by [2.3] and [3.6].


Pt C, Ch 2, Sec 3

3.15.3 The system is to allow for the broadcast of messagesfrom the navigation bridge and from other places on boardthe ship as deemed necessary.

3.15.4 The system is to be protected against unauthoriseduse.

3.15.5 The system is to be installed with regard to acousti-cally marginal conditions and not require any action fromthe addressee.

3.15.6 Where an individual loudspeaker has a device forlocal silencing, an override arrangement from the controlstation(s), including the navigating bridge, is to be in place.

3.15.7 With the ship underway in normal conditions, theminimum sound pressure level for broadcasting emergencyannouncements is to be:

a) in interior spaces, 75 dB (A) and at least 20 dB (A) abovethe speech interference level

b) in exterior spaces, 80 dB (A) and at least 15 dB (A)above the speech interference level.

With respect to cabin/state rooms, the sound pressure levelis to be attained as required inside such spaces during seatrials.

3.16 Combined general emergency alarm-public address system

3.16.1 Where the public address system is the only meansfor sounding the general emergency alarm signal and thefire alarm, in addition to the requirements of [3.14] and[3.15], the following are to be satisfied:

• the system automatically overrides any other non emer-gency input system when an emergency alarm isrequired

• the system automatically overrides any volume controlprovided to give the required output for the emergencymode when an emergency alarm is required

• the system is arranged to prevent feedback or otherinterference

• the system is arranged to minimise the effect of a singlefailure so that the alarm signal is still audible (aboveambient noise levels) also in the case of failure of anyone circuit or component, by means of the use of:

- multiple amplifiers

- segregated cable routes to public rooms, alleyways,stairways and control stations

- more than one device for generating electronicsound signal

- electrical protection for individual loudspeakersagainst short-circuits.

3.17 Control and indication circuits

3.17.1 For the supply of automation systems, comprisingcontrol, alarm and safety system, see the requirements ofPart C, Chapter 3.

3.17.2 Control and indicating circuits relative to primaryessential services are to be branched off from the main cir-cuit in which the relevant equipment is installed. Equivalentarrangements may be accepted by the Society.

3.17.3 Control and indicating circuits relative to secondaryessential services and to non-essential services may be sup-plied by distribution systems reserved for the purpose to thesatisfaction of the Society.

3.18 Power supply to the speed control systems of main propulsion engines

3.18.1 Electrically operated speed control systems of mainengines are to be fed from the main source of electricalpower.

3.18.2 Where more than one main propulsion engine isforeseen, each speed control system is to be provided withan individual supply by means of separate wiring from themain switchboard or from two independent section boards.

Where the main busbars are divided into two sections, thegovernors are, as far as practicable, to be supplied equallyfrom the two sections.

3.18.3 In the case of propulsion engines which do notdepend for their operation on electrical power, i.e. pumpsdriven from the main engine, the speed control systems areto be fed both from the main source of electrical power andfrom an accumulator battery for at least 15 minutes or froma similar supply source.

Such battery may also be used for other services such asautomation systems, where foreseen.

3.19 Power supply to the speed control systems of generator sets

3.19.1 Each electrically operated control and/or speed con-trol system of generator sets is to be provided with a sepa-rate supply from the main source of electric power and froman accumulator battery for at least 15 minutes or from asimilar supply source.

3.19.2 The speed control system of generator sets is to besupplied from the main switchboard or from independentsection boards.

Where the main busbars are divided into two sections, thegovernors are, as far as practicable, to be supplied from thesections to which the relevant generators are connected.

3.20 Installation of water-based local application fire-fighting systems (FWBLAFFS)

3.20.1 The system is to be capable of manual release.

3.20.2 The activation of the fire-fighting system is not toresult in loss of electrical power or reduction of themanoeuvrability of the ship.


Pt C, Ch 2, Sec 3

3.20.3 The system and its components are to be designedto withstand ambient temperature changes, vibration,humidity, shock, impact, clogging and corrosion normallyencountered in machinery spaces. Components within theprotected spaces are to be designed to withstand the ele-vated temperatures which could occur during a fire.

3.20.4 Degrees of protection are to be in accordance with[4.2].

3.20.5 Systems requiring an external power source are tobe supplied by the main power source.

3.20.6 In case of activation of the system, an alarm inaccordance with Ch 4, Sec 6, [4.7.4] is to be activated.

4 Degrees of protection of the enclosures

4.1 General

4.1.1 The minimum required degree of protection for elec-trical equipment, in relation to the place of installation, isgenerally that specified in Tab 2.

4.1.2 Equipment supplied at nominal voltages in excess of500 V and accessible to non-authorised personnel (e.g.equipment not located in machinery spaces or in lockedcompartments under the responsibility of the ship’s officers)is to have a degree of protection against touching live partsof at least IP 4X.

4.1.3 In addition to the requirements of this paragraph,equipment installed in spaces with an explosion hazard isalso subject to the provisions of Ch 2, Sec 2, [6].

4.1.4 The enclosures of electrical equipment for the moni-toring and control of watertight doors which are situatedbelow the bulkhead deck are to provide suitable protectionagainst the ingress of water.

In particular, the minimum required degree of protection isto be:

• IP X7 for electric motors, associated circuits and controlcomponents

• IP X8 for door position indicators and associated circuitcomponents

• IP X6 for door movement warning signals.

Note 1: The water pressure testing of the enclosures protected toIP X8 is to be based on the pressure that may occur at the locationof the component during flooding for a period of 36 hours.

4.2 Installation of electrical and electronic equipment in engine rooms protected by fixed water-based local application fire-fighting systems (FWBLAFFS)

4.2.1 Unless it is essential for safety or operational pur-poses, electrical and electronic equipment is not to belocated within areas protected by FWBLAFFS and in adja-cent areas where water may extend.

The electrical and electronic equipment located withinareas protected by FWBLAFFS and those within adjacentexposed to direct spray are to have a degree of protectionnot less than IP44.

Electrical and electronic equipment within adjacent areasnot exposed to direct spray may have a lower degree of pro-tection provided evidence of suitability for use in theseareas is submitted taking into account the design and equip-ment layout, e.g. position of inlet ventilation openings, fil-ters, baffles, etc. to prevent or restrict the ingress mist/sprayinto the equipment. The cooling airflow for the equipmentis to be assured.

Note 1: Definitions (see Fig 2):

• protected space is a machinery space where a FWBLAFFS isinstalled

• protected areas: areas within a protected space which isrequired to be protected by FWBLAFFS

• adjacent areas:

- areas other those protected areas, exposed

- areas other those defined above, where water may extend.

Note 2: Additional precautions may be required to be taken inrespect of:

• tracking as the result of water entering the equipment

• potential damage as the result of residual salts from sea watersystems

• high voltage installations

• personnel protection against electric shock

Equipment may require maintenance after being subjected to watermist/spray.

Figure 2 : Definitions of areas

� ��

��

��

��

��


Pt C, Ch 2, Sec 3

Table 2 : Minimum required degrees of protection

Condition in location

Example oflocation

Switch-board,

control gear, motorstarters

Gener-ators

MotorsTrans-

formersLumi-naires

Heat-ing

appli-ances

Cook-ing

appli-ances

Socket outlets

Accessories (e.g.

switches, connection

boxes)

Danger oftouching live parts only

Dry accommoda-tion spaces, dry control rooms

IP 20 X (1) IP 20 IP 20 IP 20 IP 20 IP 20 IP 20 IP 20

Danger ofdripping liquid and/ormoderate mechanical damage

Control rooms, wheel-house, radio room

IP 22 X IP 22 IP 22 IP 22 IP 22 IP 22 IP 22 IP 22

Engine and boiler rooms above floor

IP 22 IP 22 IP 22 IP 22 IP 22 IP 22 IP 22 IP 44 IP 44

Steering gear rooms

IP 22 IP 22 IP 22 IP 22 IP 22 IP 22 X IP 44 IP 44

Emergency machinery rooms

IP 22 IP 22 IP 22 IP 22 IP 22 IP 22 X IP 44 IP 44

Generalstorerooms

IP 22 X IP 22 IP 22 IP 22 IP 22 X IP 22 IP 44

Pantries IP 22 X IP 22 IP 22 IP 22 IP 22 IP 22 IP 44 IP 44

Provision rooms IP 22 X IP 22 IP 22 IP 22 IP 22 X IP 44 IP 44

Ventilation ducts X X IP 22 X X X X X X

Increaseddanger ofliquid and/ormechanical damage

Bathrooms and/or showers

X X X X IP 34 IP 44 X IP 55 IP 55

Engine and boiler rooms below floor

X X IP 44 X IP 34 IP 44 X X IP 55

Closed fuel oil separator rooms

IP 44 X IP 44 IP 44 IP 34 IP 44 X X IP 55

Closedlubricating oil separator rooms

IP 44 X IP 44 IP 44 IP 34 IP 44 X X IP 55

Increaseddanger ofliquid and mechanical damage

Ballast pump rooms

IP 44 XIP 44 (2)

IP 44 (2)

IP 34 IP 44 X IP 55 IP 55

Refrigerated rooms

X X IP 44 X IP 34 IP 44 X IP 55 IP 55

Galleys andlaundries

IP 44 X IP 44 IP 44 IP 34 IP 44 IP 44 IP 44 IP 44

Public bathrooms and shower

X X IP 44 IP 44 IP 34 IP 44 X IP 44 IP 44

Danger ofliquid spraying,presence of cargo dust,serious mechani-cal damage, aggressive fumes

Shaft or pipetunnels in double bottom

IP 55 X IP 55 IP 55 IP 55 IP 55 X IP 56 IP 56

Holds for general cargo

X X IP 55 X IP 55 IP 55 X IP 56 IP 56

Ventilation trunks X X IP 55 X X X X X X

Danger of liquid in massivequantities

Open decks IP 56 X IP 56 X IP 55 IP 56 X IP 56 IP 56

(1) The symbol “X” denotes equipment which it is not advised to install.(2) Electric motors and starting transformers for lateral thrust propellers located in spaces similar to ballast pump rooms may have

degree of protection IP 22.


Pt C, Ch 2, Sec 3

Table 3 : Required environmental categories

5 Diversity (demand) factors

5.1 General

5.1.1 The cables and protective devices of final sub-circuitsare to be rated in accordance with their connected load.

5.1.2 Circuits supplying two or more final sub-circuits areto be rated in accordance with the total connected loadsubject, where justifiable, to the application of a diversity(demand) factor.

5.1.3 A diversity (demand) factor may be applied providedthat the known or anticipated operating conditions in a par-ticular part of an installation are suitable for the applicationof diversity.

6 Environmental categories of the equipment


6.1.1 The environmental categories of the electrical equip-ment, in relation to the place of installation, are generally tobe those specified in Tab 3.

6.1.2 For ships operating outside the tropical belt, the max-imum ambient air temperature may be assumed as equal to+ 40°C instead of + 45°C, so that the first characteristicnumeral changes from 1 to 3.

7 Electrical protection

7.1 General requirements for overcurrent protection

7.1.1 Electrical installations are to be protected againstaccidental overcurrents including short-circuit.The choice, arrangement and performance of the variousprotective devices are to provide complete and coordinatedautomatic protection in order to ensure as far as possible:• continuity of service in the event of a fault, through

coordinated and discriminative action of the protectivedevices

• elimination of the effects of faults to reduce damage tothe system and the hazard of fire as far as possible.

Note 1: An overcurrent is a current exceeding the nominal current.

Note 2: A short-circuit is the accidental connection by a relativelylow resistance or impedance of two or more points in a circuitwhich are normally at different voltages.

7.1.2 Devices provided for overcurrent protection are to bechosen according to the requirements, especially withregard to overload and short-circuit.Note 1: Overload is an operating condition in an electricallyundamaged circuit which causes an overcurrent.

7.1.3 Systems are to be such as to withstand the thermaland electrodynamic stresses caused by the possible overcur-rent, including short-circuit, for the admissible duration.

7.2 Short-circuit currents

7.2.1 In calculating the maximum prospective short-circuitcurrent, the source of current is to include the most power-ful configuration of generators which can be simultaneouslyconnected (as far as permitted by any interlocking arrange-ments), and the maximum number of motors which are nor-mally simultaneously connected in the system.The maximum number of generators or transformers is to beevaluated without taking into consideration short-term par-allel operation (e.g. for load transfer) provided that suitableinterlock is foreseen.

7.2.2 Short-circuit current calculations are to be performedin accordance with a method recognised by the Society,such as that given in IEC Publication 61363-1.

7.2.3 In the absence of precise data concerning the charac-teristics of generators, accumulator batteries and motors,the maximum short-circuit currents on the main busbarsmay be calculated as follows:• for alternating current systems:

Iac = 10 ITG + 3,5 ITM

Ipk = 2,4 Iac

• for direct current systems supplied by batteries:Ip = K C10 + 6 ITM

where:

Location within main area

Main areas on board GeneralInside cubicles,

desks, etc. On machinery such as internal

combustion engines, compressorsMasts

Machinery spaces, steering gear EC21 EC31 EC23 X (1)

Control room, accommodation EC21EC11C

EC31 X X

Bridge EC21EC11C

EC31

X X

Pump room, holds, rooms without heating EC41 X X X

Exposed decks EC41S X X EC42S

(1) The symbol “X” denotes locations which are generally not applicable.


Pt C, Ch 2, Sec 3

Ip : Maximum short-circuit current

Iac : r.m.s. value of the symmetrical component (atthe instant T/2)

Ipk : Maximum peak value

ITG : Rated current of all generators which can beconnected simultaneously

C10 : Battery capacity in Ah for a discharge durationof 10 hours

K : Ratio of the short-circuit current of the batteriesto C10 (see [7.2.3], Note 1)

ITM : Rated current of all motors which are normallysimultaneously connected in the system.

Note 1: For stationary batteries the following values may beassumed for guidance:

• vented lead-acid batteries: K = 8

• vented alkaline type batteries intended for discharge at lowrates corresponding to a battery duration exceeding threehours: K = 15

• sealed lead-acid batteries having a capacity of 100 Ah or moreor alkaline type batteries intended for discharge at high ratescorresponding to a battery duration not exceeding three hours:K = 30.

7.3 Selection of equipment

7.3.1 Circuit-breakers of withdrawable type are requiredwhere they are not suitable for isolation.

7.3.2 Equipment is to be chosen on the basis of its ratedcurrent and its making/breaking capacity.

7.3.3 In the selection of circuit-breakers with intentionalshort-time delay for short-circuit release, those of utilisationcategory B are to be used and they are to be selected alsotaking into account their rated short-time withstand currentcapacity (Icw).

For circuit-breakers without intentional short-time delay forshort-circuit release, circuit breakers of utilisation categoryA may be used and they are to be selected according totheir rated service short-circuit breaking capacity (Ics).

Note 1: For the purpose of these Rules, utilisation categories A andB are defined as follows:

• utilisation category A: circuit-breakers not specifically intendedfor selectivity under short-circuit conditions with respect toother short-circuit protective devices in series on the load side,i.e. without an intentional short-time delay provided for selec-tivity under short-circuit conditions

• utilisation category B: circuit-breakers specifically intended forselectivity under short-circuit conditions with respect to othershort-circuit protective devices in series on the load side, i.e.with an intentional short-time delay (which may be adjustable)provided for selectivity under short-circuit conditions.

7.3.4 For duplicated essential services and non-essentialservices, circuit-breakers may be selected according to theirultimate short-circuit breaking capacity (Icu).

7.3.5 For switches, the making/breaking capacity is to be inaccordance with utilisation category AC-22 A or DC-22 A(in compliance with IEC Publication 60947-3).

7.3.6 For fuse-switch disconnectors or switch-disconnectorfuse units, the making/breaking capacity is to be in accor-dance with utilisation categories AC-23 A or DC-23 A (incompliance with IEC Publication 60947-3).

7.4 Protection against short-circuit

7.4.1 Protection against short-circuit currents is to be pro-vided by circuit- breakers or fuses.

7.4.2 The rated short-circuit breaking capacity of every pro-tective device is to be not less than the maximum prospec-tive value of the short-circuit current at the point ofinstallation at the instant of contact separation.

7.4.3 The rated short-circuit making capacity of everymechanical switching device intended to be capable ofbeing closed on short-circuit is to be not less than the maxi-mum value of the short-circuit current at the point of instal-lation. On alternating current this maximum valuecorresponds to the peak value allowing for maximum asym-metry.

7.4.4 Every protective device or contactor not intended forshort-circuit interruption is to be adequate for the maximumshort-circuit current liable to occur at the point of installa-tion having regard to the time required for the short-circuitto be removed.

7.4.5 The use of a protective device not having a short-cir-cuit breaking or making capacity at least equal to the maxi-mum prospective short-circuit current at the point where itis installed is permitted, provided that it is backed up on thegenerator side by a fuse or by a circuit-breaker having atleast the necessary short-circuit rating and not being thegenerator circuit-breaker.

7.4.6 The same fuse or circuit-breaker may back up morethan one circuit-breaker where the circuits concerned donot involve essential services.

7.4.7 The short-circuit performance of the back-up arrange-ment is to be equal to the requirements of IEC Publication60947-2 for a single circuit-breaker having the same short-circuit performance category as the backed-up circuit-breaker and rated for the maximum prospective short-cir-cuit level at the supply terminals of the arrangement.

7.4.8 Circuit-breakers with fuses connected to the load sidemay be used, provided the back-up fuses and the circuit-breakers are of coordinated design, in order to ensure thatthe operation of the fuses takes place in due time so as toprevent arcing between poles or against metal parts of thecircuit-breakers when they are submitted to overcurrentsinvolving the operation of the fuse.

7.4.9 When determining the performance requirements forthe above-mentioned back-up protection arrangement, it ispermissible to take into account the impedance of the vari-ous circuit elements of the arrangement, such as the imped-ance of a cable connection when the backed-up circuit-breaker is located away from the back-up breaker or fuse.


Pt C, Ch 2, Sec 3

7.5 Continuity of supply and continuity of service

7.5.1 The protection of circuits is to be such that a fault inone service does not cause the loss of any essential services.

7.5.2 The protection of the emergency circuit is to be suchthat a failure in one circuit does not cause a loss of otheremergency services.

Note 1: The continuity of supply for the primary essential servicesand the continuity of service for the secondary essential servicesare to be ensured.

The continuity of supply is the condition for which during and aftera fault in a circuit, the supply to the healthy circuits (see circuit 3 inFig 3) is permanently ensured.

The continuity of service is the condition for which after a fault in acircuit has been cleared, the supply to the healthy circuits (see cir-cuit 3 in Fig 3) is re-established.

7.6 Protection against overload

7.6.1 Devices provided for overload protection are to havea tripping characteristic (overcurrent-trip time) adequate forthe overload ability of the elements of the system to be pro-tected and for any discrimination requirements.

7.6.2 The use of fuses up to 320 A for overload protectionis permitted.

7.7 Localisation of overcurrent protection

7.7.1 Short-circuit protection is to be provided for everynon-earthed conductor.

7.7.2 Overload protection is to be provided for every non-earthed conductor nevertheless, in insulated single-phasecircuits or insulated three-phase circuits having substan-tially balanced loads, the overload protection may be omit-ted on one conductor.

7.7.3 Short-circuit and overload protective devices are notto interrupt earthed conductors, except in the case of multi-ple disconnection devices which simultaneously interruptall the conductors, whether earthed or not.

7.7.4 Electrical protection is to be located as close as possi-ble to the origin of the protected circuit.

7.8 Protection of generators

7.8.1 Generators are to be protected against short-circuitsand overloads by multipole circuit-breakers.

For generators not arranged to operate in parallel with arated output equal to or less than 50 kVA, a multipoleswitch with a fuse in each insulated phase on the generatorside may be accepted.

7.8.2 When multipole switch and fuses are used, the fuserating is to be maximum 110% of the generator rated cur-rent.

Figure 3 : Continuity of supply and continuity of service

Con

tinui

ty o

f sup

ply

Con

tinui

ty o

f ser

vice

1 1

2 3 2 3

Before a fault During a fault After a fault

1

2 3

1 1 1

2 32 32 3 2 32 3


Pt C, Ch 2, Sec 3

7.8.3 Where a circuit-breaker is used:

a) The overload protection is to trip the generator circuit-breaker at an overload between 10% and 50%. For anoverload of 50% of the rated current of the generator,the time delay is not to exceed 2 minutes. However, thefigure of 50% or the time delay of 2 minutes may beexceeded if the construction of the generator permitsthis.

b) the setting of the short-circuit protection is to instanta-neously trip the generator circuit-breaker at an overcur-rent less than the steady short-circuit current of thegenerator. Short time delays (e.g. from 0,5 s to 1 s) maybe introduced for discrimination requirements in"instantaneous" tripping devices.

7.8.4 For emergency generators the overload protectionmay, instead of disconnecting the generator automatically,give a visual and audible alarm in a permanently attendedspace.

7.8.5 After disconnection of a generator due to overload,the circuit-breaker is to be ready for immediate reclosure.

7.8.6 Generator circuit-breakers are to be provided with areclosing inhibitor which prevents their automatic reclosureafter tripping due to a short-circuit.

7.8.7 Generators having a capacity of 1500 kVA or aboveare to be equipped with a suitable protective device or sys-tem which, in the event of a short-circuit in the generator orin the supply cable between the generator and its circuit-breaker, will de-excite the generator and open the circuit-breaker (e.g. by means of differential protection).

7.8.8 Where the main source of electrical power is neces-sary for the propulsion of the ship, load shedding or otherequivalent arrangements are to be provided to protect thegenerators against sustained overload.

7.8.9 Arrangements are to be made to disconnect or reduceautomatically the excess load when the generators are over-loaded in such a way as to prevent a sustained loss of speedand/or voltage (see Ch 2, Sec 2, Tab 6). The operation ofsuch device is to activate a visual and audible alarm. A timedelay of 5-20 s is considered acceptable.

7.8.10 When an overload is detected the load sheddingsystem is to disconnect automatically, after an appropriatetime delay, the circuits supplying the non-essential servicesand, if necessary, the secondary essential services in a sec-ond stage.

7.8.11 Alternating current generators arranged to operatein parallel are to be provided with reverse-power protec-tion.

The protection is to be selected in accordance with thecharacteristics of the prime mover.

The following values are recommended:

• 2-6% of the rated power for turbogenerators

• 8-15% of the rated power for diesel generators.

The reverse-power protection may be replaced by otherdevices ensuring adequate protection of the prime movers.

7.8.12 Generators are to be provided with an undervoltageprotection which trips the breaker if the voltage falls to70%-35% of the rated voltage.

The undervoltage release also prevents the closing of thecircuit-breaker if the generator voltage does not reach aminimum of 85% of the rated voltage.

The operation of the undervoltage release is to be instanta-neous when preventing closure of the breaker, but it is to bedelayed for selectivity purposes when tripping the breaker.

7.9 Protection of circuits

7.9.1 Each separate circuit shall be protected against short-circuit and against overload, unless otherwise specified inthese Rules or where the Society may exceptionally other-wise permit.

7.9.2 Each circuit is to be protected by a multipole circuit-breaker or switch and fuses against overloads and short-cir-cuits.

7.9.3 Circuits for lighting are to be disconnected on bothnon-earthed conductors. Single-pole disconnection of finalsub-circuits with both poles insulated is permitted only inaccommodation spaces, when a differential protection isprovided.

7.9.4 The protective devices of the circuits supplyingmotors are to allow excess current to pass during transientstarting of motors.

7.9.5 Final sub-circuits which supply one consumer withits own overload protection (for example motors), or con-sumers which cannot be overloaded (for example perma-nently wired heating circuits and lighting circuits), may beprovided with short-circuit protection only.

7.9.6 Steering gear circuits are to be provided with short-circuit protection only (see Ch 1, Sec 11, [2]).

7.10 Protection of motors

7.10.1 Motors of rating exceeding 1 kW and all motors foressential services are to be protected individually againstoverload and short-circuit. The short-circuit protection maybe provided by the same protective device for the motorand its supply cable (see [7.9.5]).

7.10.2 For motors intended for essential services, the over-load protection may be replaced by an overload alarm (forsteering gear motors see Ch 1, Sec 11, [2]).

7.10.3 The protective devices are to be designed so as toallow excess current to pass during the normal acceleratingperiod of motors according to the conditions correspondingto normal use.

If the current/time characteristic of the overload protectiondevice does not correspond to the starting conditions of amotor (e.g. for motors with extra-long starting period), pro-vision may be made to suppress operation of the deviceduring the acceleration period on condition that the short-circuit protection remains operative and the suppression ofoverload protection is only temporary.


Pt C, Ch 2, Sec 3

7.10.4 For continuous duty motors the protective gear is tohave a time delay characteristic which ensures reliable ther-mal protection against overload.

7.10.5 The protective devices are to be adjusted so as tolimit the maximum continuous current to a value within therange 105% - 120% of the motor’s rated full load current.

7.10.6 For intermittent duty motors the current setting andthe delay (as a function of time) of the protective devices areto be chosen in relation to the actual service conditions ofthe motor.

7.10.7 Where fuses are used to protect polyphase motorcircuits, means are to be provided to protect the motoragainst unacceptable overload in the case of single phasing.

7.10.8 Motors rated above 1 kW are to be provided with:

• undervoltage protection, operative on the reduction orfailure of voltage, to cause and maintain the interruptionof power in the circuit until the motor is deliberatelyrestarted or

• undervoltage release, operative on the reduction or fail-ure of voltage, so arranged that the motor restarts auto-matically when power is restored after a power failure.

7.10.9 The automatic restart of a motor is not to produce astarting current such as to cause excessive voltage drop.

In the case of several motors required to restart automati-cally, the total starting current is not to cause an excessivevoltage drop or sudden surge current to this end, it may benecessary to achieve a sequence start.

7.10.10 The undervoltage protective devices are to allowthe motor to be started when the voltage exceeds 85% ofthe rated voltage and are to intervene without fail when thevoltage drops to less than approximately 20% of the ratedvoltage, at the rated frequency and with a time delay as nec-essary.

7.11 Protection of storage batteries

7.11.1 Batteries are to be protected against overload andshort-circuit by means of fuses or multipole circuit-breakersat a position adjacent to the battery compartment.

Overcurrent protection may be omitted for the circuit to thestarter motors when the current drawn is so large that isimpracticable to obtain short-circuit protection.

7.11.2 Emergency batteries supplying essential services areto have short-circuit protection only.

7.12 Protection of shore power connection

7.12.1 Permanently fixed cables connecting the shore con-nection box to the main switchboard are to be protected byfuses or circuit-breakers (see [3.7.4]).

7.13 Protection of measuring instruments, pilot lamps and control circuits

7.13.1 Measuring circuits and devices (voltage transform-ers, voltmeters, voltage coils of measuring instruments,

insulation monitoring devices etc.) and pilot lamps are to beprotected against short-circuit by means of multipole cir-cuit-breakers or fuses.

The protective devices are to be placed as near as possibleto the tapping from the supply.

The secondary side of current transformers is not to be pro-tected.

7.13.2 Control circuits and control transformers are to beprotected against overload and short-circuit by means ofmultipole circuit-breakers or fuses on each pole not con-nected to earth.

Overload protection may be omitted for transformers with arated current of less than 2 A on the secondary side.

The short-circuit protection on the secondary side may beomitted if the transformer is designed to sustain permanentshort-circuit current.

7.13.3 Where a fault in a pilot lamp would impair the oper-ation of essential services, such lamps are to be protectedseparately from other circuits such as control circuits.

Note 1: Pilot lamps connected via short-circuit-proof transformersmay be protected in common with control circuits.

7.13.4 Circuits whose failure could endanger operation,such as steering gear control feeder circuits, are to be pro-tected only against short-circuit.

7.13.5 The protection is to be adequate for the minimumcross-section of the protected circuits.

7.14 Protection of transformers

7.14.1 The primary winding side of power transformers isto be protected against short-circuit and overload by meansof multipole circuit-breakers or switches and fuses.

Overload protection on the primary side may be dispensedwith where it is provided on the secondary side or when thetotal possible load cannot reach the rated power of thetransformer.

7.14.2 The protection against short-circuit is to be such asto ensure the selectivity between the circuits supplied bythe secondary side of the transformer and the feeder circuitof the transformer.

7.14.3 When transformers are arranged to operate in paral-lel, means are to be provided so as to trip the switch on thesecondary winding side when the corresponding switch onthe primary side is open.

8 System components

8.1 General

8.1.1 The components of the electrical system are to bedimensioned such as to withstand the currents that can passthrough them during normal service without their ratingbeing exceeded.


Pt C, Ch 2, Sec 3

8.1.2 The components of the electrical system are to bedesigned and constructed so as to withstand for the admissi-ble duration the thermal and electrodynamic stressescaused by possible overcurrents, including short-circuit.

9 Electrical cables

9.1 General

9.1.1 All electrical cables and wiring external to equipmentshall be at least of a flame-retardant type, in accordancewith IEC Publication 60332-1.

9.1.2 In addition to the provisions of [9.1.1], when cablesare laid in bunches, cable types are to be chosen in compli-ance with IEC Publication 60332-3 Category A, or othermeans (see Ch 2, Sec 12) are to be provided such as not toimpair their original flame-retarding properties.

9.1.3 Where necessary for specific applications such asradio frequency or digital communication systems, whichrequire the use of particular types of cables, the Society maypermit the use of cables which do not comply with the pro-visions of [9.1.1] and [9.1.2].

9.1.4 Cables which are required to have fire-resisting char-acteristics are to comply with the requirements stipulated inIEC Publication 60331.

9.2 Choice of insulation

9.2.1 The maximum rated operating temperature of theinsulating material is to be at least 10°C higher than themaximum ambient temperature liable to occur or to be pro-duced in the space where the cable is installed.

9.2.2 The maximum rated conductor temperature for nor-mal and short-circuit operation, for the type of insulatingcompounds normally used for shipboard cables, is not toexceed the values stated in Tab 4. Special consideration willbe given to other insulating materials.

9.2.3 PVC insulated cables are not to be used either inrefrigerated spaces, or on decks exposed to the weather ofships classed for unrestricted service.

9.2.4 Mineral insulated cables will be considered on a caseby case basis.

9.3 Choice of protective covering

9.3.1 The conductor insulating materials are to be enclosedin an impervious sheath of material appropriate to theexpected ambient conditions where cables are installed inthe following locations:

• on decks exposed to the weather

• in damp or wet spaces (e.g. in bathrooms)

• in refrigerated spaces

• in machinery spaces and, in general

• where condensation water or harmful vapour may bepresent.

9.3.2 Where cables are provided with armour or metallicbraid (e.g. for cables installed in hazardous areas), an over-all impervious sheath or other means to protect the metallicelements against corrosion is to be provided (see Ch 2, Sec9, [1.5]).

9.3.3 An impervious sheath is not required for single-corecables installed in tubes or ducts inside accommodationspaces, in circuits with maximum system voltage 250 V.

9.3.4 In choosing different types of protective coverings,due consideration is to be given to the mechanical action towhich each cable may be subjected during installation andin service.

If the mechanical strength of the protective covering is con-sidered insufficient, the cables are to be mechanically pro-tected (e.g. by an armour or by installation inside pipes orconduits).

Table 4 : Maximum rated conductor temperature

Type of insulating compoundAbbreviated designation

Maximum rated conductortemperature, in °C

Normal operation Short-circuit

a) Thermoplastic:

- based upon polyvinyl chloride or copolymer of vinyl chloride and vinyl acetate PVC 70 150

b) Elastomeric or thermoset:

- based upon ethylene-propylene rubber or similar (EPM or EPDM) EPR 90 250

- based upon high modulus or hard grade ethylene propylene rubber HEPR 90 250

- based upon cross-linked polyethylene XLPE 90 250

- based upon silicone rubber S 95 95 350 (1)

- based upon ethylene-propylene rubber or similar (EPM or EPDM) halogen-free HF EPR 90 250

- based upon high modulus or hard grade halogen-free ethylene propylene rubber HF HEPR 90 250

- based upon halogen-free cross-linked polyethylene HF XLPE 90 250

- based upon halogen-free silicone rubber HF S 95 95 350 (1)

- based upon cross-linked polyolefin material for halogen-free cables HF 90 90 250

(1) This temperature is applicable only to power cables and not appropriate for tinned copper conductors.


Pt C, Ch 2, Sec 3

9.3.5 Single-core cables for a.c. circuits with rated currentexceeding 20 A are to be either non-armoured or armouredwith non-magnetic material.

9.4 Cables in refrigerated spaces

9.4.1 Cables installed in refrigerated spaces are to have awatertight or impervious sheath and are to be protectedagainst mechanical damage. If an armour is applied on thesheath, the armour is to be protected against corrosion by afurther moisture-resisting covering.

9.5 Cables in areas with a risk of explosion

9.5.1 For cables in areas with a risk of explosion, see[10.2].

9.6 Cables in circuits required to be opera-ble under fire condition

9.6.1 Electrical services required to be operable under fireconditions are as follows:

• control and power systems to power-operated fire doorsand status indication for all fire doors

• control and power systems to power-operated watertightdoors and their status indication

• emergency fire pump

• emergency lighting

• fire and general alarms

• fire detection systems

• fire-extinguishing systems and fire-extinguishing mediarelease alarms

• low location lighting

• public address systems

• remote emergency stop/shutdown arrangements for sys-tems which may support the propagation of fire and/orexplosion.

9.6.2 Where cables for services specified in [9.6.1] includ-ing their power supplies pass through high fire risk areas,and, in addition for passenger ships, through main verticalfire zones other than those which they serve, they are to beso arranged that a fire in any of these areas or zones doesnot affect the operation of the service in any other area orzone. This may be achieved by either of the following mea-sures:

a) Cables being of a fire resistant type complying with IEC60331 are to be installed and run continuous to keepthe fire integrity within the high fire risk area (see Fig 4)

b) At least two-loops/radial distributions run as widelyapart as is practicable and so arranged that in the eventof damage by fire at least one of the loops/radial distri-butions remains operational.

Systems that are self monitoring, fail safe or duplicated withcable runs as widely separated as is practicable may beexempted.

9.6.3 Cables for services required to be operable under fireconditions, including their power supplies, are to be run asdirectly as is practicable.

9.6.4 Cables connecting fire pumps to the emergencyswitchboard shall be of a fire-resistant type where they passthrough high fire risk areas.

9.7 Cables for submerged bilge pumps

9.7.1 Cables and their connections to such pumps are to becapable of operating under a head of water equal to theirdistance below the bulkhead deck. The cable is to beimpervious-sheathed and armoured, is to be installed incontinuous lengths from above the bulkhead to the motorterminals and is to enter the air bell from the bottom.

Figure 4 : Routing of cables in high fire risk area

��

��

��

��

��


Pt C, Ch 2, Sec 3

9.8 Internal wiring of switchboards and other enclosures for equipment

9.8.1 For installation in switchboards and other enclosuresfor equipment, single-core cables may be used without fur-ther protection (sheath).

Other types of flame-retardant switchboard wiring may beaccepted at the discretion of the Society.

9.9 Current carrying capacity of cables

9.9.1 The current carrying capacity for continuous serviceof cables given in Tab 5 to Tab 9 is based on the maximumpermissible service temperature of the conductor also indi-cated therein and on an ambient temperature of 45°C.

9.9.2 The current carrying capacity cited in [9.9.1] is appli-cable, with rough approximation, to all types of protectivecovering (e.g. both armoured and non-armoured cables).

9.9.3 Values other than those shown in Tab 5 to Tab 9 maybe accepted provided they are determined on the basis ofcalculation methods or experimental values approved bythe Society.

9.9.4 When the actual ambient temperature obviously dif-fers from 45°C, the correction factors shown in Tab 10 maybe applied to the current carrying capacity in Tab 5 to Tab 9.

Table 5 : Current carrying capacity, in A, in continuous service for cables based on maximum conductor oper-ating temperature of 60°C (ambient temperature 45°C)



Nominal section, in mm2

Number of conductors1 2 3 or 4

1,5 10 9 72,5 17 14 12

4 23 20 166 29 25 20

10 40 34 2816 54 46 3825 71 60 5035 88 75 6250 110 94 7770 135 115 9595 164 139 115120 189 161 132150 218 185 153

185 248 211 174240 292 248 204300 336 286 235

400dc: 390ac: 380

dc: 332ac: 323

dc: 273ac: 266

500dc: 450ac: 430

dc: 383ac: 366

dc: 315ac: 301

630dc: 520ac: 470

dc: 442ac: 400

dc: 364ac: 329

Nominal section,in mm2


1,5 21 18 152,5 28 24 204 38 32 276 49 42 34

10 67 57 4716 91 77 6425 120 102 8435 148 126 10450 184 156 12970 228 194 16095 276 235 193

120 319 271 223150 367 312 257185 418 355 293240 492 418 344300 565 480 396

400dc: 650ac: 630

dc: 553ac: 536

dc: 455ac: 441

500dc: 740ac: 680

dc: 629ac: 578

dc: 518ac: 476

630dc: 840ac: 740

dc: 714ac: 629

dc: 588ac: 518

Nominal section, in mm2


1,5 15 13 112,5 21 18 15

4 29 25 206 37 31 26

10 51 43 3616 68 58 4825 90 77 6335 111 94 7850 138 117 9770 171 145 12095 207 176 145

120 239 203 167150 275 234 193

185 313 266 219240 369 314 258300 424 360 297

400dc: 500ac: 490

dc: 425ac: 417

dc: 350ac: 343

500dc: 580ac: 550

dc: 493ac: 468

dc: 406ac: 385

630dc: 670ac: 610

dc: 570ac: 519

dc: 469ac: 427


Pt C, Ch 2, Sec 3



Table 10 : Correction factors for various ambient air temperatures

9.9.5 Where more than six cables are bunched together insuch a way that there is an absence of free air circulatingaround them, and the cables can be expected to be underfull load simultaneously, a correction factor of 0,85 is to beapplied.

9.9.6 Where a cable is intended to supply a short-time loadfor 1/2-hour or 1-hour service (e.g. mooring winches orbow thruster propellers), the current carrying capacityobtained from Tab 5 to Tab 9 may be increased by applyingthe corresponding correction factors given in Tab 11.

In no case is a period shorter than 1/2-hour to be used,whatever the effective period of operation.

9.9.7 For supply cables to single services for intermittentloads (e.g. cargo winches or machinery space cranes), thecurrent carrying capacity obtained from Tab 5 to Tab 9 maybe increased by applying the correction factors given in Tab12.

The correction factors are calculated with rough approxi-mation for periods of 10 minutes, of which 4 minutes with aconstant load and 6 minutes without load.

Nominal section (mm2)

Number of conductors

1 2 3 or 4

1,5 23 20 16

2,5 30 26 21

4 40 34 28

6 52 44 36

10 72 61 50

16 96 82 67

25 127 108 89

35 157 133 110

50 196 167 137

70 242 206 169

95 293 249 205

120 339 288 237

150 389 331 272

185 444 377 311

240 522 444 365

300 601 511 421

400dc: 690ac: 670

dc: 587ac: 570

dc: 483ac: 469

500dc: 780ac: 720

dc: 663ac: 612

dc: 546ac: 504

630dc: 890ac: 780

dc: 757ac: 663

dc: 623ac: 546

Nominal section (mm2)

Number of conductors

1 2 3 or 4

1,5 26 22 18

2,5 32 27 22

4 43 37 30

6 55 47 39

10 76 65 53

16 102 87 71

25 135 115 95

35 166 141 116

50 208 177 146

70 256 218 179

95 310 264 217

120 359 305 251

150 412 350 288

185 470 400 329

240 553 470 387

300 636 541 445

400dc: 760ac: 725

dc: 646ac: 616

dc: 532ac: 508

500dc: 875ac: 810

dc: 744ac: 689

dc: 612ac: 567

630dc: 1010ac: 900

dc: 859ac: 765

dc: 707ac: 630

Maximum conductor temperature, in °C

Correction factors for ambient air temperature of:

35°C 40°C 45°C 50°C 55°C 60°C 65°C 70°C 75°C 80°C 85°C

60 1,29 1,15 1,00 0,82 − − − − − − −65 1,22 1,12 1,00 0,87 0,71 − − − − − −70 1,18 1,10 1,00 0,89 0,77 0,63 − − − − −75 1,15 1,08 1,00 0,91 0,82 0,71 0,58 − − − −80 1,13 1,07 1,00 0,93 0,85 0,76 0,65 0,53 − − −85 1,12 1,06 1,00 0,94 0,87 0,79 0,71 0,61 0,50 − −90 1,10 1,05 1,00 0,94 0,88 0,82 0,74 0,67 0,58 0,47 −95 1,10 1,05 1,00 0,95 0,89 0,84 0,77 0,71 0,63 0,55 0,45


Pt C, Ch 2, Sec 3

Table 11 : Correction factors for short-time loads

Table 12 : Correction factors for intermittent service

9.9.8 The current carrying capacity of cables connected inparallel is the sum of the current ratings of all parallel con-ductors but the cables must have equal impedance, equalcross-section, equal maximum permissible conductor tem-peratures and follow substantially identical routing or be

installed in close proximity. Connections in parallel are onlypermitted for cross-sections of 10 mm2 or above. Whenequal impedance can not be assumed, a correction factor of0,9 is to be applied to the current carrying capacity.

9.10 Minimum nominal cross-sectional area of conductors

9.10.1 In general the minimum allowable conductor cross-sectional areas are those given in Tab 13.

9.10.2 The nominal cross-sectional area of the neutral con-ductor in three-phase distribution systems is to be equal toat least 50% of the cross-sectional area of the phases, unlessthe latter is less than or equal to 16 mm2. In such case thecross-sectional area of the neutral conductor is to be equalto that of the phase.

9.10.3 For the nominal cross-sectional area of:

• earthing conductors, see Ch 2, Sec 12, [2.3]

• earthing connections for distribution systems, see Ch 2,Sec 12, [2.5]

• neutral connections for three-phase systems, see Ch 2,Sec 8, [1.2.4].

Table 13 : Minimum nominal cross-sectional areas

1/2-hour service 1-hour service

Correctionfactor

Sum of nominal cross-sectional areas of all conductors, in mm2

Sum of nominal cross-sectional areas of all conductors, in mm2

Cables with metallic sheath and armoured cables

Cables with non-metallic sheath and non-armoured

cables

Cables with metallic sheath and armoured cables

Cables with non-metallic sheath and non-armoured

cables

up to 20 up to 75 up to 80 up to 230 1,06

21 - 41 76 - 125 81 - 170 231 - 400 1,10

41 - 65 126 - 180 171 - 250 401 - 600 1,15

66 - 95 181 - 250 251 - 430 601 - 800 1,20

96 - 135 251 - 320 431 - 600 − 1,25

136 - 180 321 - 400 601 - 800 − 1,30

181 - 235 401 - 500 − − 1,35

236 - 285 501 - 600 − − 1,40

286 - 350 − − − 1,45

Sum of nominal cross-sectional areasof all conductors, in mm2

Correction factorCables with

metallic sheath and armoured cables

Cables withoutmetallic sheath and

non-armoured cables

S ≤ 5 1,10

5 < S ≤ 8 1,15

8 < S ≤ 16 1,20

S ≤ 4 16 < S ≤ 25 1,25

4 < S ≤ 7 25 < S ≤ 42 1,30

7 < S ≤ 17 42 < S ≤ 72 1,35

17 < S ≤ 42 72 < S ≤ 140 1,40

42 < S ≤ 110 140 < S 1,45

110 < S − 1,50

ServiceNominal cross-sectional area, in mm2

External wiring Internal wiring

Power, heating and lighting systems 1,0 1,0

Control circuits for power plant 1,0 1,0

Control circuits other than those for power plant 0,75 0,5

Control circuits for telecommunications, measurement, alarms 0,5 0,2

Telephone and bell equipment, not required for the safety of the ship or crew calls 0,2 0,1

Bus and data cables 0,2 0,1


Pt C, Ch 2, Sec 3

9.11 Choice of cables

9.11.1 The rated voltage of any cable is to be not lowerthan the nominal voltage of the circuit for which it is used.

9.11.2 The nominal cross-sectional area of each cable is tobe sufficient to satisfy the following conditions with refer-ence to the maximum anticipated ambient temperature:

• the current carrying capacity is to be not less than thehighest continuous load carried by the cable

• the voltage drop in the circuit, by full load on this cir-cuit, is not to exceed the specified limits

• the cross-sectional area calculated on the basis of theabove is to be such that the temperature increaseswhich may be caused by overcurrents or starting tran-sients do not damage the insulation.

9.11.3 The highest continuous load carried by a cable is tobe calculated on the basis of the power requirements and ofthe diversity factor of the loads and machines suppliedthrough that cable.

9.11.4 When the conductors are carrying the maximumnominal service current, the voltage drop from the main oremergency switchboard busbars to any point in the installa-tion is not to exceed 6% of the nominal voltage.

For battery circuits with supply voltage less than 55 V, thisvalue may be increased to 10%.

For the circuits of navigation lights, the voltage drop is notto exceed 5% of the rated voltage under normal conditions.

10 Electrical installations in hazardous areas

10.1 Electrical equipment

10.1.1 No electrical equipment is to be installed in hazard-ous areas unless the Society is satisfied that such equipmentis:

• essential for operational purposes

• of a type which will not ignite the mixture concerned

• appropriate to the space concerned, and

• appropriately certified for safe usage in the dusts,vapours or gases likely to be encountered.

10.1.2 Where electrical equipment of a safe type is permit-ted in hazardous areas it is to be selected with due consid-eration to the following:

a) risk of explosive dust concentration (see Ch 2, Sec 2,[6.2]):

• degree of protection of the enclosure

• maximum surface temperature

b) risk of explosive gas atmosphere (see Ch 2, Sec 2, [6.1]):

• explosion group

• temperature class.

10.1.3 Where electrical equipment is permitted in hazard-ous areas, all switches and protective devices are to inter-rupt all poles or phases and, where practicable, to belocated in a non-hazardous area unless specifically permit-ted otherwise.

Such switches and equipment located in hazardous areasare to be suitably labelled for identification purposes.

10.1.4 Electrical installations in hazardous areas are to beinspected by skilled personnel at their initial installationand regularly during their life time.

The requirements of IEC 60079-17 apply.

10.1.5 For electrical equipment installed in Zone 0 hazard-ous areas, only the following types are permitted:

• certified intrinsically-safe apparatus Ex(ia)

• simple electrical apparatus and components (e.g. ther-mocouples, photocells, strain gauges, junction boxes,switching devices), included in intrinsically-safe circuitsof category “ia” not capable of storing or generatingelectrical power or energy in excess of limits stated inthe relevant rules, and accepted by the appropriateauthority

• equipment specifically designed and certified by theappropriate authority for use in Zone 0.


• any type that may be considered for Zone 0

• certified intrinsically-safe apparatus Ex(ib)

• simple electrical apparatus and components (e.g. ther-mocouples, photocells, strain gauges, junction boxes,switching devices), included in intrinsically-safe circuitsof category “ib” not capable of storing or generatingelectrical power or energy in excess of limits stated inthe relevant rules, and accepted by the appropriateauthority

• certified flameproof Ex(d)

• certified pressurised Ex(p)

• certified increased safety Ex(e)

• certified encapsulated Ex(m)

• certified sand filled Ex(q)

• certified specially Ex(s)

• through runs of cable.


• any type that may be considered for Zone 1

• tested specially for Zone 2 (e.g. type “n” protection)

• pressurised, and accepted by the appropriate authority

• encapsulated, and accepted by the appropriate author-ity

• the type which ensures the absence of sparks and arcsand of “hot spots” during its normal operation (mini-mum class of protection IP 55).

10.1.8 When apparatus incorporates a number of types ofprotection, it is to be ensured that all are suitable for use inthe zone in which it is located.


Pt C, Ch 2, Sec 3

10.2 Electrical cables

10.2.1 Electrical cables are not to be installed in hazardousareas except as specifically permitted or when associatedwith intrinsically safe circuits.

10.2.2 All cables installed in Zone 0, Zone 1 or weatherexposed areas are to be sheathed with at least one of thefollowing:

a) a non-metallic impervious sheath in combination withbraiding or other metallic covering

b) a copper or stainless steel sheath (for mineral insulatedcables only).

10.2.3 All cables installed in non-weather exposed Zone 2areas are to be provided with at least a non-metallic exter-nal impervious sheath.

10.2.4 Cables of intrinsically safe circuits are to have ametallic shielding with at least a non-metallic externalimpervious sheath.

10.2.5 The circuits of a category “ib” intrinsically safe sys-tem are not to be contained in a cable associated with a cat-egory “ia” intrinsically safe system required for a hazardousarea in which only category “ia” systems are permitted.

10.3 Electrical installations in battery rooms

10.3.1 Only lighting fittings may be installed in compart-ments assigned solely to large vented storage batteries (seeCh 2, Sec 11, [6.2.1]).

The associated switches are to be installed outside suchspaces.

Electric ventilator motors are to be outside ventilation ductsand, if within 3 m of the exhaust end of the duct, they are tobe of an explosion-proof safe type. The impeller of the fan isto be of the non-sparking type.

Overcurrent protective devices are to be installed as closeas possible to, but outside of, battery rooms.

Electrical cables other than those pertaining to the equip-ment arranged in battery rooms are not permitted.

10.3.2 Electrical equipment for use in battery rooms is tohave minimum explosion group IIC and temperature classT1.

10.3.3 Standard marine electrical equipment may beinstalled in compartments assigned solely to valve-regu-lated sealed storage batteries.

10.4 Electrical installations in paint stores or enclosed spaces leading to paint stores

10.4.1 Electrical equipment is to be installed in paint storesand in ventilation ducts serving such spaces only when it isessential for operational services.

Certified safe type equipment of the following type isacceptable:

• certified intrinsically-safe apparatus Ex(i)

• certified flameproof Ex(d)

• certified pressurised Ex(p)

• certified increased safety Ex(e)

• certified specially Ex(s).

Cables (through runs or termination cables) of armouredtype or installed in metallic conduit are to be used.

10.4.2 Switches, protective devices and motor control gearof electrical equipment installed in a paint store are to inter-rupt all poles or phases and are preferably to be located in anon hazardous space.

10.4.3 Electrical equipment for use in paint stores is tohave minimum explosion group IIB and temperature classT3.

10.4.4 In the areas on open deck within 1 m of inlet andexhaust ventilation openings of paint stores or 3 m ofexhaust mechanical ventilation outlets of such spaces, fol-lowing electrical equipment may be installed:

• electrical equipment with the type of protection as per-mitted in paint stores, or

• equipment of protection class Exn, or

• appliances which do not generate arcs in service andwhose surface does not reach unacceptably high tem-perature, or

• appliances with simplified pressurised enclosures orvapour proof enclosures (minimum class of protectionIP55) whose surface does not reach unacceptably hightemperature

• cables as specified in [10.4.1].

10.4.5 Enclosed spaces giving access to paint stores maybe considered as non-hazardous, provided that:

• the door to the paint store is a gastight door with self-closing devices without holding back arrangements

• the paint store is provided with an acceptable, indepen-dent, natural ventilation system ventilated from a safearea

• warning notices are fitted adjacent to the paint storeentrance stating that the store contains flammable liq-uids.

Note 1: The paint stores and inlet and exhaust ventilation ductsunder [10.4.4] are classified as Zone 1 and areas on open deckunder [10.4.4] are classified as Zone 2 as defined in IEC standard60092-502.

Note 2: A watertight door may be considered as being gastight.

10.5 Electrical installations in stores for welding gas (acetylene) bottles

10.5.1 The following equipment may be installed in storesfor welding gas bottles provided that it is of a safe typeappropriate for Zone 1 area installation:

• lighting fittings

• ventilator motors where provided.


Pt C, Ch 2, Sec 3

10.5.2 Electrical cables other than those pertaining to theequipment arranged in stores for welding gas bottles are notpermitted.

10.5.3 Electrical equipment for use in stores for weldinggas bottles is to have minimum explosion group IIC andtemperature class T2.

10.6 Special ships

10.6.1 For installations in hazardous areas in:• oil tankers, chemical tankers and liquefied gas carriers,

see Pt D, Ch 7, Sec 5, Pt D, Ch 8, Sec 10 or Pt D, Ch 9,Sec 10

• ships arranged with spaces for the carriage of vehicles,see Pt D, Ch 1, Sec 4 or Pt D, Ch 12, Sec 4.


Pt C, Ch 2, Sec 4

SECTION 4 ROTATING MACHINES

1 Constructional and operational requirements for generators and motors

1.1 Mechanical construction

1.1.1 Materials and construction of electrical machines areto conform to the relevant requirements of Ch 2, Sec 2, [4]and Ch 2, Sec 2, [5].

1.1.2 Shafts are to be made of material complying with theprovisions of NR216 Materials and Welding, Ch 2, Sec 3 or,where rolled products are allowed in place of forgings, withthose of NR216 Materials and Welding, Ch 2, Sec 1.

1.1.3 Where welded parts are foreseen on shafts and rotors,the provisions of NR216 Materials and Welding, Chapter 5are to apply.

1.1.4 Sleeve bearings are to be efficiently and automati-cally lubricated at all running speeds.

Provision is to be made for preventing the lubricant fromgaining access to windings or other insulated or bare cur-rent carrying parts.

1.1.5 Means are to be provided to prevent bearings frombeing damaged by the flow of currents circulating betweenthem and the shaft. According to the manufacturer’srequirements, electrical insulation of at least one bearing isto be considered.

1.1.6 For surface-cooled machines with an external faninstalled on the open deck, adequate protection of the fanagainst icing is to be provided.

1.1.7 When liquid cooling is used, the coolers are to be soarranged as to avoid entry of water into the machine,whether by leakage or condensation in the heat exchanger,and provision is to be made for the detection of leakage.

1.1.8 Rotating machines whose ventilation or lubricationsystem efficiency depends on the direction of rotation are tobe provided with a warning plate.

1.2 Sliprings, commutators and brushes

1.2.1 Sliprings and commutators with their brushgear are tobe so constructed that undue arcing is avoided under allnormal load conditions.

1.2.2 The working position of brushgear is to be clearly andpermanently marked.

1.2.3 Sliprings, commutators and brushgear are to bereadily accessible for inspection, repairs and maintenance.

1.3 Terminal connectors

1.3.1 Suitable, fixed terminal connectors are to be pro-vided in an accessible position for connection of the exter-nal cables.

1.3.2 All terminal connectors are to be clearly identifiedwith reference to a diagram.

1.3.3 The degree of protection of terminal boxes is to beadequate to that of the machine.

1.4 Electrical insulation

1.4.1 Insulating materials for windings and other currentcarrying parts are to comply with the requirements of Ch 2,Sec 2, [4.2] and Ch 2, Sec 2, [4.3].

2 Special requirements for generators

2.1 Prime movers, speed governors and overspeed protection

2.1.1 Prime movers for generators are to comply with therelevant requirements of Ch 1, Sec 2, [2.7].

2.1.2 When generators are to operate in parallel, the char-acteristics of speed governors are to comply with the provi-sions of [2.2].

2.2 A.c. generators

2.2.1 Alternators are to be so constructed that, whenstarted up, they take up the voltage without the aid of anexternal electrical power source.

Where these provisions are not complied with, the externalelectrical power source is to be constituted by a batteryinstallation in accordance with the requirements for electri-cal starting systems of auxiliary machinery (see Ch 1, Sec 2).

2.2.2 The voltage wave form is to be approximately sinuso-idal, with a maximum deviation from the sinusoidal funda-mental curve of 5% of the peak value.

2.2.3 Each alternator is to be provided with automaticmeans of voltage regulation.

2.2.4 For a.c. generating sets operating in parallel, the gov-erning characteristics regarding the load are to comply withrequirement of Ch 1, Sec 2, [2.7.5].


Pt C, Ch 2, Sec 4

2.2.5 When a.c. generators are operated in parallel, thereactive loads of the individual generating sets are not todiffer from their proportionate share of the total reactiveload by more than 10% of the rated reactive power of thelargest machine, or 25% of that of the smallest machine,whichever is the lesser.

3 Testing of rotating machines

3.1 General

3.1.1 All machines are to be tested by the manufacturers.

3.1.2 All tests are to be carried out according to IEC Publi-cation 60092-301.

3.1.3 The manufacturer is to issue a test report giving, interalia, information concerning the construction, type, serialnumber, insulation class and all other technical data rele-vant to the machine, as well as the results of the testsrequired.

3.1.4 All machines of 100 KW and over, intended foressential services are to be type approved or case-by-caseapproved and surveyed by the Society during testing and, ifappropriate, during manufacturing. Tested machines are tobe individually certified by the Society.

In addition for rotating machines intended for propulsiondeveloping a power of more than 1 MW, requirementsgiven in [5] apply.

Note 1: An alternative inspection scheme may be agreed by theSociety with the manufacturer whereby the attendance of the Sur-veyor will not be required as indicated above.

3.1.5 All machines below 100 KW intended for essentialservices are to be type approved or case-by-case approved.Individual works' certificate is to be issued by the manufac-turer and detailed test report submitted to the Society.

3.1.6 For rotating machines intended for non essential ser-vices, individual works' certificate is to be issued by themanufacturer and detailed test report made available andsubmitted upon request.

3.1.7 Case-by-case approval, mentioned in [3.1.4] and[3.1.5], is to be in line with requirement given in Ch 2, Sec15, [2.1.2].

3.2 Shaft material

3.2.1 Shaft material for electric propulsion motors and formain engine driven generators where the shaft is part of thepropulsion shafting is to be certified by the Society.

3.2.2 Shaft material for other machines is to be in accor-dance with recognized international or national standard.

3.3 Tests

3.3.1 Type test are to be carried out on a proptoype machineor on the first batch of machines, and routine tests carried outon subsequent machines in accordance with Tab 1.

Table 1 : Tests to be carried out on electrical rotating machines

N° Testsa.c. Generators Motors

Type test (1) Routine test (2) Type test (1) Routine test (2)

1 Examination of the technical documentation, visual inspection in compliance with design drawings

X X X X

2 Insulation resistance measurement (stator and rotor windings)

X X X X

3 Winding resistance measurement (stator and rotor) X X X X

4 Verification of the voltage regulation system X X (3)

5 Rated load test and temperature rise measurement X X

6 Overload/overcurrent test X X (4) X X (4)

7 Verification of steady short-circuit conditions (5) X

8 Overspeed test X X X (6) X (6)

9 Dielectric strength test (stator and rotor windings) X X X X

10 No load test X X X X

11 Verification of degree of protection X X

12 Verification of bearings X X X X

(1) Type test on prototype machine or test on at least the first batch of machines.(2) The reports of machines routine tested are to contain the manufacturer’s serial number of the machine which has been type

tested and the test result.(3) Only functional test of the voltage regulator system.(4) Only applicable for machine of essential services rated above 100kW/kVA.(5) Verification of steady short-circuit condition applies to synchronous machines only.(6) Not applicable for squirrel cage motors.


Pt C, Ch 2, Sec 4

3.3.2 Where the test procedure is not specified, therequirements of IEC 60034-1 apply.

4 Description of test

4.1 Technical documentation and visual inspection

4.1.1 Technical documentation of machines rated at 100kW (kVA) and over are to be available for examination bythe Surveyor.

4.1.2 A visual inspection of the machine is to be made toensure, as far as practicable, that it complies with the tech-nical documentation.

4.2 Insulation resistance measurement

4.2.1 Immediately after the high voltage tests the insulationresistances are to be measured using a direct current insula-tion tester between:

a) all current carrying parts connected together and earth

b) all current carrying parts of different polarity or phase,where both ends of each polarity or phase are individu-ally accessible.

The minimum values of test voltages and correspondinginsulation resistances are given in Tab 2. The insulationresistance is to be measured close to the operating tempera-ture, or an appropriate method of calculation is to be used.

Table 2 : Minimum insulation resistance

4.3 Winding resistance measurement

4.3.1 The resistances of the machine windings are to bemeasured and recorded using an appropriate bridgemethod or voltage and current method.

4.4 Verification of the voltage regulation

4.4.1 The alternating current generator, together with itsvoltage regulation system, is to be verified in such a waythat, at all loads from no load running to full load, the ratedvoltage at the rated power factor is maintained under steadyconditions within ± 2,5%. These limits may be increased to± 3,5% for emergency sets.

4.4.2 When the generator is driven at rated speed, giving itsrated voltage, and is subjected to a sudden change of sym-metrical load within the limits of specified current andpower factor, the voltage is not to fall below 85% norexceed 120% of the rated voltage.

4.4.3 The voltage of the generator is then to be restored towithin plus or minus 3% of the rated voltage for the maingenerator sets in not more than 1.5 s. For emergency sets,these values may be increased to plus or minus 4% in notmore than 5 s, respectively.

4.4.4 In the absence of precise information concerning themaximum values of the sudden loads, the following condi-tions may be assumed: 60% of the rated current with apower factor of between 0.4 lagging and zero to be sud-denly switched on with the generator running at no load,and then switched off after steady - state conditions havebeen reached.

4.5 Rated load test and temperature rise measurements

4.5.1 The temperature rises are to be measured at the ratedout-put, voltage and frequency and for the duty for whichthe machine is rated and marked in accordance with thetesting methods specified in IEC Publication 60034-1, or bymeans of a combination of other tests.

4.5.2 The limits of temperature rise above ambient air tem-perature of 45°C for air-cooled machines are those given inTab 3.

4.6 Overload/ overcurrent test

4.6.1 Overload test is to be carried out as a type test forgenerators as proof of overload capability of generators andthe excitation system, for motors as proof of momentaryexcess torque as required in IEC Publication 60034-1. Theover-load test can be replaced at a routine test by an over-current test. The overcurrent test is to be proof of the currentcapability of the windings, wires, connections etc. of eachmachine. The overcurrent test can be performed at reducedspeed (motors) or at short-circuit (generators).

Note 1: The overload test may be omitted for electrical propulsionmotor supplied by converter if an overload protection / limitation isprovided inside the converter. Justifications are to be transmitted bythe converter manufacturer.

4.6.2 In the case of machines for special uses (e.g. forwind-lasses), overload values other than the above may beconsidered.

4.7 Verification of the steady short circuit current

4.7.1 It is to be verified that under steady state short-circuitconditions, the generator with its voltage regulating systemis capable of maintaining, without sustaining any damage, acurrent of at least three times the rated current for a durationof at least 2 s or, where precise data is available, for a dura-tion of any time delay which may be fitted in a trippingdevice for discrimination purposes.

Rated voltage Un VMinimum

test voltage VMinimum insulation

resistance MΩ

Un = 250 2 Un 1

250 < Un ≤ 1000 500 1

1000 < Un ≤ 7200 1000 Un/1000 + 1

7200 < Un ≤ 15000 5000 Un/1000 + 1


Pt C, Ch 2, Sec 4

Table 3 : Temperature rise limits for air-cooled machines based on an ambient temperature of 45°C

4.8 Overspeed test

4.8.1 Machines are to withstand the overspeed test as spec-ified in IEC Publication 60034-1. This test is not applicablefor squirrel cage motors.

4.9 Dielectric strength test

4.9.1 New and completed rotating machines are to with-stand a dielectric test as specified in IEC Publication 60034-1.

4.9.2 For high voltage machines an impulse test is to becarried out on the coils according to Ch 2, Sec 13.

4.9.3 When it is necessary to perform an additional highvoltage test, this is to be carried out after any further drying,with a test voltage of 80% of that specified in IEC Publica-tion 60034-1.

4.9.4 Completely rewound windings of used machines areto be tested with the full test voltage applied in the case ofnew machines.

4.9.5 Partially rewound windings are to be tested at 75% ofthe test voltage required for new machines. Prior to the test,the old part of the winding is to be carefully cleaned anddried.

4.9.6 Following cleaning and drying, overhauled machinesare to be subjected to a test at a voltage equal to 1,5 timesthe rated voltage, with a minimum of 500 V if the rated volt-age is less than 100 V, and with a minimum of 1000 V if therated voltage is equal to or greater than 100 V.

4.9.7 A repetition of the high voltage test for groups ofmachines and apparatus is to be avoided if possible, but if atest on an assembled group of several pieces of new appara-tus, each of which has previously passed its high voltagetest, is per-formed, the test voltage to be applied to suchassembled group is 80% of the lowest test voltage appropri-ate for any part of the group.

Note 1: For windings of one or more machines connected togetherelectrically, the voltage to be considered is the maximum voltagethat occurs in relation to earth.

N° Part of machinesMethod of

measurement of temperature (1)

Temperature rise, in °C,by class of insulation

A E B F H

1 a) a.c. windings of machines having outputs of 5000 kW(or kVA) or more

RETD

5560

−−

7580

95100

120125

b) a.c. windings of machines having outputs of less than 5000 kW (or kVA)

RETD

5560

70−

7585

100105

120125

2 Windings of armatures with commutators TR

4555

6070

6575

80100

100120

3 Field windings of a.c. and d.c machines having d.c. excitation other than those in item 4

TR

4555

6070

6575

80100

100120

4 a) Field windings of synchronous machines with cylindrical rotors having d.c. excitation

R − − 85 105 130

b) Stationary field windings of d.c. machines having more than one layer

TR

ETD

4555−

6070−

657585

80100105

100120130

c) Low resistance field windings of more than one layer, and compensating windings

T, R (2) 55 70 75 95 120

d) Single-layer windings with exposed bare surfaces T, R (2) 60 75 85 105 130

5 Permanently short-circuited, insulated windings T 55 70 75 95 120

6 Permanently short-circuited uninsulated windings The temperature rise of these parts is in no case to reach such a value that there is a risk of damage to any insulating or other material on adjacent parts

7 Magnetic core and other parts not in contact with windings

8 Magnetic core and other parts in contact with windings T 55 70 75 95 120

9 Commutators and sliprings, open or enclosed (3) T 55 65 75 85 95

(1) T : Measurement by the thermometer methodR : Measurement by the resistance methodETD : Measurement by embedded temperature detectors.

(2) Temperature rise measurement is to use the resistance method R whenever practicable.(3) If commutators and sliprings are adjacent to windings with a lower insulation class, the temperature rises for this class apply.


Pt C, Ch 2, Sec 4

4.10 No load test

4.10.1 Machines are to be operated at no load and ratedspeed whilst being supplied at rated voltage and frequencyas a motor while generators are to be driven by a suitablemeans and excited to give rated terminal voltage.During the running test, the vibration of the machine andoperation of the bearing lubrication system, if appropriate,are to be checked.

4.11 Verification of degree of protection

4.11.1 As specified in IEC Publication 60034-5.

4.12 Verification of bearings

4.12.1 Upon completion of the above tests, machineswhich have sleeve bearings are to be opened upon requestfor examination by the Surveyor, to establish that the shaft iscorrectly seated in the bearing shells.

5 Additional tests for rotating machines used as propulsion motor or thruster

5.1 General

5.1.1 In addition to the tests defined in Tab 1, rotatingmachines used as propulsion motor or thruster and devel-oping a power of more than 1 MW are to be subjected tothe following requirements and tests during their assembly:

a) Shaft line

• requirements of Ch 1, Sec 7 apply

b) Rotor winding assembly

• dynamic balancing

c) Stator winding assembly

• dielectric test (after impregnation)

• insulation resistance measurement (after impregna-tion)

d) Frame

• visual examination in compliance with design draw-ings

• liquid penetrant test of 10% of the structure weldsand 100% of the handling points.

e) Watercooler

• visual examination in compliance with design draw-ings

• performance test (see temperature rise measurementtest in Tab 1)

f) Hydrostatic jacking unit

• pressure test

• working test under nominal conditions


Pt C, Ch 2, Sec 5

SECTION 5 TRANSFORMERS

1 Constructional and operational requirements

1.1 Construction

1.1.1 Transformers, except those for motor starting, are tobe double wound (two or more separate windings).

1.1.2 Transformers are normally to be of the dry, air-cooledtype.

1.1.3 When a forced air cooling system is used, an alarm isto be activated in the event of its failure.

1.1.4 Liquid-cooled transformers may be used providedthat:

• the liquid is non-toxic and of a type which does notreadily support combustion

• the construction is such that the liquid is not spilled ininclined position

• temperature and pressure relief devices with an alarmare installed

• drip trays or other suitable arrangements for collectingthe liquid from leakages are provided

• a liquid gauge indicating the normal liquid level rangeis fitted.

1.1.5 Transformers are to have enclosures with a degree ofprotection in accordance with Ch 2, Sec 3, Tab 2.

1.2 Terminals

1.2.1 Suitable fixed terminal connections are to be pro-vided in an accessible position with sufficient space forconvenient connection of the external cables.

1.2.2 Terminals are to be clearly identified.

1.3 Voltage variation, short-circuit condi-tions and parallel operation

1.3.1 Under resistive load (cos Φ = 1), the voltage dropfrom no load to full load is not to exceed 2,5%.

For transformers with a power lower than 5 kVA per phase,this voltage drop is not to exceed 5%.

An exception is made for special transformers, such as start-ing and instrument transformers, for which a different volt-age variation may be considered.

1.3.2 In determining the voltage ratio and the impedancevoltage of transformers, account is to be taken of the totalpermitted voltage drop from the main switchboard’s busbarsto the consumers (see Ch 2, Sec 3, [9.11.4]).

1.3.3 Transformers are to be constructed to withstand,without damage, the thermal and mechanical effects of asecondary terminal short-circuit for 2 s, with rated primaryvoltage and frequency.For transformers of 1 MVA and over, this is to be justifiedwith appropriate tests or documentation.

1.3.4 When transformers are so arranged that their second-ary windings may be connected in parallel, their windingconnections are to be compatible, their rated voltage ratiosare to be equal (with tolerances allowed) and their short-cir-cuit impedance values, expressed as a percentage, are tohave a ratio within 0,9 to 1,1.When transformers are intended for operation in parallel,the rated power of the smallest transformer in the group is tobe not less than half of the rated power of the largest trans-former in the group.

1.4 Electrical insulation and temperature rise

1.4.1 Insulating materials for windings and other currentcarrying parts are to comply with the requirements of Ch 2,Sec 2.

1.4.2 All windings of air-cooled transformers are to be suit-ably treated to resist moisture, air salt mist and oil vapours.

1.4.3 The permissible limits of temperature rise with anambient air temperature of 45°C for (natural or forced) air-cooled transformers are given in Tab 1. The temperaturerises shown for windings refer to measurement by the resis-tance method while those for the core refer to the thermom-eter method.

Table 1 : Temperature rise limits for transformers

N° Part of machineTemperature rise by class of insulation, in °C

A E B F H

1 Windings 55 70 75 95 120

2 Cores and other parts:

a) in contact with the windings

b) not in contact with the windings

a) the same values as for the windings

b) in no case is the temperature to reach values such as to damage either the core itself or other adjacent parts or materials


Pt C, Ch 2, Sec 5

1.4.4 For dry-type transformers cooled with an external liq-uid cooling system, the permissible limits of temperaturerise with a sea water temperature of 32°C are 13°C higherthan those specified in Tab 1.

1.4.5 For liquid-cooled transformers, the following temper-ature rises measured by the resistance method apply:• 55°C where the fluid is cooled by air• 68°C where the fluid is cooled by water.

1.5 Insulation tests

1.5.1 Transformers are to be subjected to a high voltage testin accordance with the procedure defined in IEC publica-tion 60076-3.

1.5.2 The test voltage is to be applied between each wind-ing under test and the other windings not under test, coreand enclosure all connected together.Single-phase transformers for use in a polyphase group areto be tested in accordance with the requirements applicableto that group.

1.5.3 The r.m.s. value of the test voltage is to be equal to2 U + 1000 V, with a minimum of 2500 V, where U is therated voltage of the winding. The full voltage is to be main-tained for 1 minute.

1.5.4 Partially rewound windings are to be tested at 80% ofthe test voltage required for new machines.

1.5.5 The insulation resistance of a new, clean and drytransformer, measured after the temperature rise test hasbeen carried out (at or near operating temperature) at a volt-age equal to 500 V d.c., is to be not less than 5 MΩ.

1.5.6 Transformers are to be subjected to an induced volt-age insulation test by applying to the terminals of the wind-ing under test a voltage equal to twice the rated voltage. Theduration of the test is to be 60 s for any test frequency fp upto and including twice the rated frequency fn.If the test frequency exceeds twice the rated frequency, thetest time in seconds will be 120 fn / fp with a minimum of15 s.

2 Testing

2.1 General

2.1.1 On new transformers intended for essential servicesthe tests specified in [2.2] are to be carried out.

2.1.2 The manufacturer is to issue a test report giving, interalia, information concerning the construction, type, serialnumber, insulation class and all other technical data rele-vant to the transformer, as well as the results of the testsrequired.

Such test reports are to be made available to the Society.

2.1.3 In the case of transformers which are completelyidentical in rating and in all other constructional details, itwill be acceptable for the temperature rise test to be per-formed on only one transformer.

The results of this test and the serial number of the testedtransformer are to be inserted in the test reports for the othertransformers.

2.1.4 Where the test procedure is not specified, therequirements of IEC 60076 apply.

2.1.5 The tests and, if appropriate, manufacture of trans-formers of 100 kVA and over (60 kVA when single phase)intended for essential services are to be attended by a Sur-veyor of the Society.

Transformers of 5 kVA up to the limit specified above areapproved on a case by case basis, at the discretion of theSociety, subject to the submission of adequate documenta-tion and routine tests.

2.2 Tests on transformers

2.2.1 Tests to be carried out on transformers are specifiedin Tab 2.

Table 2 : Tests to be carried out on transformers

N° Tests Type test (1) Routine test (2)

1 Examination of the technical documentation, as appropriate, and visual inspection (3) X X

2 Insulation resistance measurement X X

3 Voltage drop X X

4 High voltage test X X

5 Temperature rise measurement X

6 Induced voltage test X X

7 Voltage ratio X X

(1) Type test on prototype transformer or test on at least the first batch of transformers.(2) The certificates of transformers routine tested are to contain the manufacturer’s serial number of the transformer which has been

type tested and the test result.(3) A visual examination is to be made of the transformer to ensure, as far as practicable, that it complies with technical

documentation.


Pt C, Ch 2, Sec 6

SECTION 6 SEMICONDUCTOR CONVERTORS

1 Constructional and operational requirements

1.1 Construction

1.1.1 Semiconductor convertors are generally to complywith the requirements for switchgear assemblies (see Ch 2,Sec 8).

1.1.2 The monitoring and control circuits are generally tocomply with the requirements of Part C, Chapter 3.

1.1.3 For liquid-cooled convertors the following provisionsare to be satisfied:

• liquid is to be non-toxic and of low flammability

• drip trays or other suitable means are to be provided tocontain any liquid leakages

• the resistivity of the cooling fluid in direct contact withsemiconductor or other current carrying parts is to bemonitored and an alarm initiated if the resistivity is out-side the specified limits.

1.1.4 Where forced cooling is used, the temperature of theheated cooling medium is to be monitored.

If the temperature exceeds a preset value an alarm is to begiven and the shutdown of the convertor is to be activated.

1.1.5 Where forced (air or liquid) cooling is provided, it isto be so arranged that the convertor cannot be or remainloaded unless effective cooling is maintained.

Alternatively, other effective means of protection againstovertemperature may be provided.

1.1.6 Stacks of semiconductor elements, and other equip-ment such as fuses, or control and firing circuit boards etc.,are to be so arranged that they can be removed from equip-ment without dismantling the complete unit.

1.1.7 Semiconductor convertors are to be rated for therequired duty having regard to the peak loads, system tran-sient and overvoltage and to be dimensioned so as to with-stand the maximum short-circuit currents foreseen at thepoint of installation for the time necessary to trip the protec-tion of the circuits they supply.

1.2 Protection

1.2.1 Semiconductor elements are to be protected againstshort-circuit by means of devices suitable for the point ofinstallation in the network.

1.2.2 Overcurrent or overvoltage protection is to beinstalled to protect the convertor. When the semiconductorconvertor is designed to work as an inverter supplying thenetwork in transient periods, precautions necessary to limitthe current are to be taken.

1.2.3 Semiconductor convertors are not to cause distortionin the voltage wave form of the power supply at levelsexceeding the voltage wave form tolerances at the otheruser input terminals (see Ch 2, Sec 2, [2.4]).

1.2.4 An alarm is to be provided for tripping of protectivedevices against overvoltages and overcurrents in electricpropulsion convertors and for convertors for the emergencysource of power.

1.3 Parallel operation with other power sources

1.3.1 For convertors arranged to operate in parallel withother power sources, load sharing is to be such that undernormal operating conditions overloading of any unit doesnot occur and the combination of paralleled equipment isstable.

1.4 Temperature rise

1.4.1 The permissible limit of temperature rise of the enclo-sure of the semiconductors is to be assessed on the basis ofan ambient air temperature of 45°C or sea water tempera-ture of 32°C for water-cooled elements, taking into accountits specified maximum permissible temperature value.

1.4.2 The value of the maximum permissible temperatureof the elements at the point where this can be measured(point of reference) is to be stated by the manufacturer.

1.4.3 The value of the mean rated current of the semicon-ductor element is to be stated by the manufacturer.

1.5 Insulation test

1.5.1 The test procedure is that specified in IEC Publication60146.

1.5.2 The effective value of the test voltage for the insula-tion test is to be as shown in Tab 1.


Pt C, Ch 2, Sec 6

Table 1 : Test voltages for high voltage teston static convertors

2 Requirements for uninterruptible power system (UPS) units as alternative and/or transitional power

2.1 Definitions

2.1.1 Uninterruptible power system (UPS)

Combination of converters, switches and energy storagemeans, for example batteries, constituting a power systemfor maintaining continuity of load power in case of inputpower failure (see IEC Publication 62040).

2.1.2 Off line UPS unit

A UPS unit where under normal operation the output loadis powered from the bypass line (raw mains) and only trans-ferred to the inverter if the bypass supply fails or goes out-side preset limits. This transition will invariably result in abrief (typically 2 to 10 ms) break in the load supply.

2.1.3 Line interactive UPS unit

An off-line UPS unit where the bypass line switch to storedenergy power when the input power goes outside the presetvoltage and frequency limits.

2.1.4 On line UPS unit

A UPS unit where under normal operation the output loadis powered from the inverter, and will therefore continue tooperate without break in the event of the supply input fail-ing or going outside preset limits.

2.2 Design and construction

2.2.1 UPS units are to be constructed in accordance withIEC 62040, or an acceptable and relevant national or inter-national standard.

2.2.2 The operation of the UPS is not to depend uponexternal services.

2.2.3 The type of UPS unit employed, whether off-line, lineinteractive or on-line, is to be appropriate to the power sup-ply requirements of the connected load equipment.

2.2.4 An external bypass is to be provided.

2.2.5 The UPS unit is to be monitored and audible andvisual alarm is to be given in a normally attended locationfor:

• power supply failure (voltage and frequency) to the con-nected load

• earth fault

• operation of battery protective device

• when the battery is being discharged

• when the bypass is in operation for on-line UPS units.

2.3 Location

2.3.1 The UPS unit is to be suitably located for use in anemergency.

2.3.2 UPS units utilising valve regulated sealed batteriesmay be located in compartments with normal electricalequipment, provided the ventilation arrangements are inaccordance with the requirements of IEC 62040 or anacceptable and relevant national or international standard.

2.4 Performance

2.4.1 The output power is to be maintained for the durationrequired for the connected equipment as stated in Ch 2, Sec3, [3.6.3] and Pt D, Ch 11, Sec 5, [2.2.3].

2.4.2 No additional circuits are to be connected to the UPSunit without verification that the UPS unit has adequatecapacity.

2.4.3 The UPS battery capacity is, at all times, to be capa-ble of supplying the designated loads for the time specifiedin the regulations.

2.4.4 On restoration of the input power, the rating of thecharge unit shall be sufficient to recharge the batteries whilemaintaining the output supply to the load equipment.

3 Testing

3.1 General

3.1.1 Convertors intended for essential services are to besubjected to the tests stated in [3.2].

3.1.2 The manufacturer is to issue a test report giving infor-mation on the construction, type, serial number and alltechnical data relevant to the convertor, as well as theresults of the tests required.

3.1.3 In the case of convertors which are completely identi-cal in rating and in all other constructional details, it will beacceptable for the rated current test and temperature risemeasurement stipulated in [3.2] not to be repeated.

3.1.4 The tests and, if appropriate, manufacture of conver-tors of 50 kVA and over intended for essential services areto be attended by a Surveyor of the Society.

in V (1)

Test voltageV

U ≤ 60 600

60 < U ≤ 90 900

90 < U2 U + 1000

(at least 2000)

(1) Um: highest crest value to be expected between any pair of terminals.

Um

2-------- U=


Pt C, Ch 2, Sec 6

3.2 Tests on convertors

3.2.1 Convertors are to be subjected to tests in accordancewith Tab 2.

Type tests are the tests to be carried out on a prototype con-vertor or the first of a batch of convertors, and routine testsare the tests to be carried out on subsequent convertors of aparticular type.

3.2.2 The electronic components of the convertors are tobe constructed to withstand the tests required in Ch 3, Sec6.

3.2.3 Final approval of convertors is to include completefunction tests after installation on board, performed with allship’s systems in operation and in all characteristic loadconditions.

3.3 Additional testing and survey for unin-terruptible power system (UPS) units as alternative and/or transitional power

3.3.1 UPS units of 50 kVA and over are to be surveyed bythe Society during manufacturing and testing.

3.3.2 Appropriate testing is to be carried out to demon-strate that the UPS unit is suitable for its intended environ-ment. This is expected to include as a minimum thefollowing tests:• functionality, including operation of alarms• ventilation rate• battery capacity.

3.3.3 Where the supply is to be maintained without a breakfollowing a power input failure, this is to be verified afterinstallation by practical test.

Table 2 : Tests to be carried out on static convertors


1 Examination of the technical documentation, as appropriate, and visual inspection (3) including check of earth continuity

X X

2 Light load function test to verify all basic and auxiliary functions X X

3 Rated current test X


5 Insulation test (dielectric strength test and insulation resistance measurement) X X

6 Protection of the convertors in case of failure of forced cooling system X X

(1) Type test on prototype convertor or test on at least the first batch of convertors.(2) The certificates of convertors routine tested are to contain the manufacturer’s serial number of the convertor which has been

type tested and the test result.(3) A visual examination is to be made of the convertor to ensure, as far as practicable, that it complies with technical

documentation.


Pt C, Ch 2, Sec 7

SECTION 7 STORAGE BATTERIES AND CHARGERS

1 Constructional requirements for batteries

1.1 General

1.1.1 The requirements of this Section apply to perma-nently installed storage batteries (not to portable batteries).

1.1.2 Storage batteries may be of the lead-acid or nickel-alkaline type, due consideration being given to the suitabil-ity for any specific application.

Other types of storage batteries of satisfactorily provendesign (e.g. silver/zinc) may be accepted provided they aresuitable for shipboard use to the satisfaction of the Society.

1.1.3 Cells are to be assembled in suitable crates or traysequipped with handles for convenient lifting.

1.2 Vented batteries

1.2.1 Vented batteries are those in which the electrolytecan be replaced and freely releases gas during periods ofcharge and overcharge.

1.2.2 Vented batteries are to be constructed to withstandthe movement of the ship and the atmosphere (salt mist, oiletc.) to which they may be exposed.

1.2.3 Battery cells are to be so constructed as to preventspilling of electrolyte at any inclination of the battery up to40° from the vertical.

1.2.4 It is to be possible to check the electrolyte level andthe ph.

1.3 Valve-regulated sealed batteries

1.3.1 Valve-regulated sealed batteries are batteries whosecells are closed under normal conditions but which have anarrangement which allows the escape of gas if the internalpressure exceeds a predetermined value. The cells cannotnormally receive addition to the electrolyte.

Note 1: The cells of batteries which are marketed as “sealed” or“maintenance free” are fitted with a pressure relief valve as a safetyprecaution to enable uncombined gas to be vented to the atmo-sphere; they should more properly be referred to as valve-regulatedsealed batteries. In some circumstances the quantity of gas ventedcan be up to 25% of the equivalent vented design. The design is totake into consideration provision for proper ventilation.

1.3.2 Cell design is to minimise risks of release of gas undernormal and abnormal conditions.

1.4 Tests on batteries

1.4.1 The battery autonomy is to be verified on board inaccordance with the operating conditions.

1.5 Battery maintenance

1.5.1 Where batteries are fitted for use for essential andemergency services, a schedule of such batteries is to becompiled and maintained. The schedule, which is to bereviewed by the Society, is to include at least the followinginformation regarding the battery(ies):

• maintenance/replacement cycle dates

• date(s) of last maintenance and/or replacement

• for replacement batteries in storage, the date of manu-facture and shelf life.

Note 1: Shelf life is the duration of storage under specified condi-tions at the end of which a battery retains the ability to give a spec-ified performance.

1.5.2 Procedures are to be put in place to ensure that,where batteries are replaced, they are of an equivalent per-formance type.

1.5.3 Where vented type batteries replace valve-regulatedsealed types, it is to be ensured that there is adequate venti-lation and that the Society's requirements relevant to thelocation and installation of vented types batteries are com-plied with.

1.5.4 Details of the schedule and of the procedures are tobe included in the ship's safety management system and beintegrated into the ship's operational maintenance routine,as appropriate, to be verified by the Society's surveyor.

2 Constructional requirements for chargers

2.1 Characteristics

2.1.1 Chargers are to be adequate for the batteries forwhich they are intended and provided with a voltage regu-lator.

2.1.2 In the absence of indications regarding its operation,the battery charger is to be such that the completely dis-charged battery can be recharged to 80% capacity within aperiod of 10 hours without exceeding the maximum per-missible charging current. A charging rate other than theabove (e.g. fully charged within 6 hours for batteries forstarting of motors) may be required in relation to the use ofthe battery.


Pt C, Ch 2, Sec 7

2.1.3 For floating service or for any other condition wherethe load is connected to the battery while it is on charge,the maximum battery voltage is not to exceed the safe valueof any connected apparatus.

Note 1: Consideration is to be given to the temperature variation ofthe batteries.

2.1.4 The battery charger is to be designed so that thecharging current is set within the maximum current allowedby the manufacturer when the battery is discharged and thefloating current to keep the battery fully charged.

2.1.5 Trickle charging to neutralise internal losses is to beprovided. An indication is to be provided to indicate acharging voltage being present at the charging unit.

2.1.6 Protection against reversal of the charging current isto be provided.

2.1.7 Battery chargers are to be constructed to simplifymaintenance operation. Indications are to be provided tovisualise the proper operation of the charger and for trou-bleshooting.

2.2 Tests on chargers

2.2.1 Battery chargers are to be subjected to tests in accor-dance with Tab 1.Type tests are the tests to be carried out on a prototypecharger or the first of a batch of chargers, and routine testsare the tests to be carried out on subsequent chargers of aparticular type.

2.2.2 The electronic components of the battery chargersare to be constructed to withstand the tests required in Ch3, Sec 6.

2.2.3 The tests of battery chargers of 5 kW and overintended for essential services are to be attended by a Sur-veyor of the Society.

Table 1 : Tests to be carried out on battery chargers


1 Examination of the technical documentation, as appropriate, and visual inspection (3) including check of earth continuity

X X

2 Functional tests (current and voltage regulation, quick, slow, floating charge, alarms) X X


4 Insulation test (dielectric strength test and insulation resistance measurement) X X

(1) Type test on prototype battery charger or test on at least the first batch of battery chargers.(2) The certificates of battery chargers routine tested are to contain the manufacturer’s serial number of the battery charger which

has been type tested and the test result.(3) A visual examination is to be made of the battery charger to ensure, as far as practicable, that it complies with technical

documentation.


Pt C, Ch 2, Sec 8

SECTION 8 SWITCHGEAR AND CONTROLGEAR ASSEMBLIES

1 Constructional requirements for main and emergency switchboards

1.1 Construction

1.1.1 Construction is to be in accordance with IEC Publica-tion 60092-302.

1.1.2 Where the framework, panels and doors of the enclo-sure are of steel, suitable measures are to be taken to pre-vent overheating due to the possible circulation of eddycurrents.

1.1.3 Insulating material for panels and other elements ofthe switchboard is at least to be moisture-resistant andflame-retardant.

1.1.4 Switchboards are to be of dead front type, withenclosure protection according to Ch 2, Sec 3, Tab 2.

1.1.5 Switchboards are to be provided with insulated hand-rails or handles fitted in an appropriate position at the frontof the switchboard. Where access to the rear is necessaryfor operational or maintenance purposes, an insulatedhandrail or insulated handles are to be fitted.

1.1.6 Where the aggregate capacity of generators con-nected to the main busbars exceeds 100 kVA, a separatecubicle for each generator is to be arranged with flame-retardant partitions between the different cubicles. Similarpartitions are to be provided between the generator cubi-cles and outgoing circuits.

1.1.7 Instruments, handles or push-buttons for switchgearoperation are to be placed on the front of the switchboard.All other parts which require operation are to be accessibleand so placed that the risk of accidental touching of liveparts, or accidental making of short-circuits and earthings,is reduced as far as practicable.

1.1.8 Where it is necessary to make provision for the open-ing of the doors of the switchboard, this is to be in accor-dance with one of the following requirements:

a) opening is to necessitate the use of a key or tool (e.g.when it is necessary to replace a lamp or a fuse-link)

b) all live parts which can be accidentally touched afterthe door has been opened are to be disconnected beforethe door can be opened

c) the switchboard is to include an internal barrier or shut-ter with a degree of protection not less than IP2X shield-ing all live parts such that they cannot accidentally betouched when the door is open. It is not to be possibleto remove this barrier or shutter except by the use of akey or tool.

1.1.9 All parts of the switchboard are to be readily accessi-ble for maintenance, repair or replacement. In particular,fuses are to be able to be safely inserted and withdrawnfrom their fuse-bases.

1.1.10 Hinged doors which are to be opened for operationof equipment on the door or inside are to be provided withfixing devices for keeping them in open position.

1.1.11 Means of isolation of the circuit-breakers of genera-tors and other important parts of the installation are to beprovided so as to permit safe maintenance while the mainbusbars are alive.

1.1.12 Where components with voltage exceeding thesafety voltage are mounted on hinged doors, the latter are tobe electrically connected to the switchboard by means of aseparate, flexible protective conductor.

1.1.13 All measuring instruments and all monitoring andcontrol devices are to be clearly identified with indeliblelabels of durable, flame-retardant material.

1.1.14 The rating of each circuit, together with the rating ofthe fuse or the appropriate setting of the overload protectivedevice (circuit-breaker, thermal relay etc.) for each circuit isto be permanently indicated at the location of the fuse orprotective device.

1.2 Busbars and bare conductors

1.2.1 Busbars are to be of copper or of copper-surroundedaluminium alloy if suitable for use in the marine environ-ment and if precautions are taken to avoid galvanic corro-sion.

1.2.2 All connections are to be so made as to inhibit corro-sion.

1.2.3 Busbars are to be dimensioned in accordance withIEC Publication 60092-302.

The mean temperature rise of busbars is not to exceed 45°Cunder rated current condition with an ambient air tempera-ture of 45°C (see Ch 2, Sec 2, [1.2.2]) and is not to have anyharmful effect on adjacent components. Higher values oftemperature rise may be accepted to the satisfaction of theSociety.


Pt C, Ch 2, Sec 8

1.2.4 The cross-section of neutral connection on an a.c.three-phase, four-wire system is to be at least 50% of thecross-section for the corresponding phases.

1.2.5 Bare main busbars, excluding the conductorsbetween the main busbars and the supply side of outgoingunits, are to have the minimum clearances and creepagedistances given in Tab 1. The values shown apply to clear-ances and creepage distances between live parts as well asbetween live parts and exposed conductive parts.

Note 1: Clearance is the distance between two conductive partsalong a string stretched the shortest way between such parts.Creepage distance is the shortest distance along the surface of aninsulating material between two conductive parts.

Table 1 : Clearance and creepage distances

1.2.6 Reduced values as specified in IEC Publication60092-302 may be accepted for type tested and partiallytype tested assemblies.

The reference values for the evaluation of the minimumclearances and creepage distances for these assemblies arebased on the following:

• pollution degree 3 (conductive pollution occurs, or drynon-conductive pollution occurs which becomes con-ductive due to condensation which is expected)

• overvoltage category III (distribution circuit level)

• unhomogenous field conditions (case A)

• rated operational voltage 1000 V a.c., 1500 V d.c.

• group of insulating material IIIa.

Special consideration is to be given to equipment located inspaces where a pollution degree higher than 3 is applica-ble, e.g. in diesel engine rooms.

1.2.7 Busbars and other bare conductors with their sup-ports are to be mechanically dimensioned and fixed suchthat they can withstand the stresses caused by short-circuits.

Where maximum symetrical short-circuit currents areexpected to exceed 50 kA, calculation is to be submitted tothe Society.

1.2.8 Busbars and bare conductors are to be protected,where necessary, against falling objects (e.g. tools, fuses orother objects).

1.3 Internal wiring

1.3.1 Insulated conductors for internal wiring of auxiliarycircuits of switchboards are to be constructed in accor-dance with Ch 2, Sec 9, [1.1.1].

1.3.2 All insulated conductors provided for in [1.3.1] are tobe of flexible construction and of the stranded type.

1.3.3 Connections from busbars to protective devices are tobe as short as possible. They are to be laid and secured insuch a way to minimise the risk of a short-circuit.

1.3.4 All conductors are to be secured to prevent vibrationand are to be kept away from sharp edges.

1.3.5 Connections leading to indicating and control instru-ments or apparatus mounted in doors are to be installedsuch that they cannot be mechanically damaged due tomovement of the doors.

1.3.6 Non-metallic trays for internal wiring of switchboardsare to be of flame-retardant material.

1.3.7 Control circuits are to be installed and protected suchthat they cannot be damaged by arcs from the protectivedevices.

1.3.8 Where foreseen, fixed terminal connectors for con-nection of the external cables are to be arranged in readilyaccessible positions.

1.4 Switchgear and controlgear

1.4.1 Switchgear and controlgear are to comply with IECPublication 60947 series and to be chosen from among thattype approved by the Society.

1.4.2 The characteristics of switchgear, controlgear andprotective devices for the various consumers are to be incompliance with Ch 2, Sec 3, [7].

1.5 Auxiliary circuits

1.5.1 Auxiliary circuits are to be designed in such a mannerthat, as far as practicable, faults in such circuits do notimpair the safety of the system. In particular, control circuitsare to be designed so as to limit the dangers resulting from afault between the control circuit and earth (e.g. inadvertentoperation or malfunction of a component in the installa-tion), also taking account of the earthing system of theirsupply.

1.5.2 Auxiliary circuits of essential systems are to be inde-pendent of other auxiliary circuits.

1.5.3 Common auxiliary circuits for groups of consumersare permitted only when the failure of one consumer jeop-ardises the operation of the entire system to which itbelongs.

1.5.4 Auxiliary circuits are to be branched off from themain circuit in which the relevant switchgear is used.

1.5.5 The supply of auxiliary circuits by specificallyarranged control distribution systems will be specially con-sidered by the Society.

1.5.6 Means are to be provided for isolating the auxiliarycircuits as well when the main circuit is isolated (e.g. formaintenance purposes).

1.5.7 For the protection of auxiliary circuits see Ch 2, Sec3, [7.13].

Rated insulation voltage a.c. r.m.s. or d.c.,

in V

Minimum clearance,

in mm

Minimum creep-age distance,

in mm

≤ 250> 250 to ≤ 690

> 690

152025

202535


Pt C, Ch 2, Sec 8

1.6 Instruments

1.6.1 The upper limit of the scale of every voltmeter is to benot less than 120% of the rated voltage of the circuit inwhich it is installed.

1.6.2 The upper limit of the scale of every ammeter is to benot less than 130% of the normal rating of the circuit inwhich it is installed.

1.6.3 The upper limit of the scale of every wattmeter is tobe not less than 120% of the rated voltage of the circuit inwhich it is installed.

1.6.4 Ammeters or wattmeters for use with a.c. generatorswhich may be operated in parallel are to be capable of indi-cating 15% reverse-current or reverse power, respectively.

1.6.5 For wattmeters using one current circuit only, themeasurement of the current of all generators is to be madein the same phase.

1.6.6 The rated value of the measure read, at full load, is tobe clearly indicated on the scales of instruments.

1.6.7 Frequency meters are to have a scale at least ± 5% ofthe nominal frequency.

1.6.8 The secondary windings of instrument transformersare to be earthed.

1.6.9 Each a.c. generator not operated in parallel is to beprovided with:

• 1 voltmeter

• 1 frequency meter

• 1 ammeter in each phase or 1 ammeter with a selectorswitch to enable the current in each phase to be read

• 1 three-phase wattmeter in the case of generators ratedmore than 50 kVA.

1.6.10 Each a.c. generator operated in parallel is to be pro-vided with:

• 1 three-phase wattmeter

• 1 ammeter in each phase or 1 ammeter with a selectorswitch to enable the current in each phase to be read.

1.6.11 For paralleling purposes the following are to be pro-vided:

• 2 voltmeters

• 2 frequency meters

• 1 synchroscope and synchronising indicating lamps orequivalent means.

A switch is to be provided to enable one voltmeter and onefrequency meter to be connected to each generator beforethe latter is connected to the busbars.

The other voltmeter and frequency meter are to be perma-nently connected to the busbars.

1.6.12 Each secondary distribution system is to be providedwith one voltmeter.

1.6.13 Switchboards are to be fitted with means for moni-toring the insulation level of insulated distribution systemsas stipulated in Ch 2, Sec 3, [3.2.1].

1.6.14 The main switchboard is to be fitted with a voltme-ter or signal lamp indicating that the cable between theshore-connection box and the main switchboard is ener-gised (see Ch 2, Sec 3, [3.7.7]).

1.6.15 For each d.c. power source (e.g. convertors, rectifi-ers and batteries), one voltmeter and one ammeter are to beprovided, except for d.c. power sources for starting devices(e.g. starting motor for emergency generator).

2 Constructional requirements for section boards and distribution boards

2.1 Construction

2.1.1 Section boards and distribution boards are to be con-structed, insofar as applicable, as specified for main andemergency switchboards.

2.1.2 All parts which require operation in normal use are tobe placed on the front.

2.1.3 Distribution switchboards which are provided withtwo or more supply circuits arranged for automatic standbyconnection are to be provided with positive indication ofwhich of the circuits is feeding the switchboard.

2.1.4 Where switchboard supplying essential services isprovided with a forced air cooling system, the air tempera-ture is to be monitored. An alarm is to be activated whentemperature exceeds a preset value.

3 Testing

3.1 General

3.1.1 Switchboards are to be subjected to the tests speci-fied from [3.2] to [3.4].

3.1.2 The manufacturer is to issue the relative test reportsproviding information concerning the construction, serialnumber and technical data relevant to the switchboard, aswell as the results of the tests required.

3.1.3 The tests are to be carried out prior to installation onboard.

3.1.4 The test procedures are as specified in IEC Publica-tion 60092-302.

3.1.5 The tests of main switchboards, emergency switch-boards or switchboards rated above 100 kW are to beattended by a surveyor of the Society.


Pt C, Ch 2, Sec 8

3.2 Inspection of equipment, check of wiring and electrical operation test

3.2.1 It is to be verified that the switchboard:

• complies with the approved drawings• maintains the prescribed degree of protection• is constructed in accordance with the relevant construc-

tional requirements, in particular as regards creepageand clearance distances.

3.2.2 The connections, especially screwed or bolted con-nections, are to be checked for adequate contact, possiblyby random tests.

3.2.3 Depending on the complexity of the switchboard itmay be necessary to carry out an electrical functioning test.The test procedure and the number of tests depend onwhether or not the switchboard includes complicated inter-locks, sequence control facilities, etc. In some cases it maybe necessary to conduct or repeat this test following instal-lation on board.

3.3 High voltage test

3.3.1 The test is to be performed with alternating voltage ata frequency between 25 and 100 Hz of approximately sinu-soidal form.

3.3.2 The test voltage is to be applied:

• between all live parts connected together and earth• between each polarity and all the other polarities con-

nected to earth for the test.

During the high voltage test, measuring instruments, ancil-lary apparatus and electronic devices may be disconnectedand tested separately in accordance with the appropriaterequirements.

3.3.3 The test voltage at the moment of application is not toexceed half of the prescribed value. It is then to beincreased steadily within a few seconds to its full value. Theprescribed test voltage is to be maintained for 1 minute.

3.3.4 The value of the test voltage for main and auxiliarycircuits is given in Tab 2 and Tab 3.

Table 2 : Test voltages for main circuits

Table 3 : Test voltage for auxiliary circuits

3.4 Measurement of insulation resistance

3.4.1 Immediately after the high voltage test, the insulationresistance is to be measured using a device with a directcurrent voltage of at least 500 V.

3.4.2 The insulation resistance between all current carryingparts and earth (and between each polarity and the otherpolarities) is to be at least equal to 1 MΩ.

Rated insulation voltage Ui, in V

Test voltage a.c. (r.m.s.),in V

Ui ≤ 60 1000

60 < Ui ≤ 300 2000

300 < Ui ≤ 660 2500

660 < Ui ≤ 800 3000

800 < Ui ≤ 1000 3500

Rated insulation voltage Ui, in V

Test voltage a.c. (r.m.s.),in V

Ui ≤ 12 250

12 < Ui ≤ 60 500

Ui > 60 2 Ui + 1000 (at least 1500)


Pt C, Ch 2, Sec 9

SECTION 9 CABLES

1 Constructional requirements

1.1 Construction

1.1.1 Cables and insulated wiring are generally to be con-structed in accordance with IEC Publications of the series60092-3.., as well with the provisions of this Chapter.

1.1.2 Mineral-insulated cables are to be constructedaccording to IEC Publication 60702.

1.1.3 Optical fibre cables are to be constructed in accord-ance with IEC Publication 60794.

1.1.4 Flexible cables constructed according to nationalstandards will be specially considered by the Society.

1.1.5 Cables and insulated wires other than those specifiedin IEC Publications (e.g. international or national standard)are subject to special consideration by the Society in eachcase. Those for general purposes are to be constructed ofmaterials having characteristics which produce a cable atleast equivalent to those constructed from materials referredto in IEC Publications.

1.1.6 Insulated wiring for auxiliary circuits of switchboardsmay be constituted by cables with a single conductor of thestranded type for all sections, PVC- or rubber-insulated inaccordance with the Publications cited in [1.1.1] and with-out further protection.

The insulated wiring is to be at least of the flame-retardanttype according to IEC Publication 60332-1. Equivalenttypes of flame-retardant switchboard wires will be speciallyconsidered by the Society.

1.1.7 Fire resistant cables are to be designed and tested inaccordance with the relevant IEC Publication 60092-seriesStandards and comply with the requirements of IEC 60331-1for cables of greater than 20 mm overall diameter, otherwiseIEC 60331-21.

Note 1: For installation methods refer to those specified in Ch 2,Sec 12, [7.1.4].

Note 2: Fire resistant type cables are to be easily distinguishable.

Note 3: For special cables, requirements in the following standardsmay be used :

• IEC 60331-23: Procedures and requirements - Electric datacables

• IEC331-25: Procedures and requirements - Optical fiber cables

1.2 Conductors

1.2.1 Conductors are to be of annealed electrolytic copperwith a resistivity not exceeding 17,241 Ω mm2/km at 20°Caccording to IEC 60228.

1.2.2 Individual conductor wires of rubber-insulated cablesare to be tinned or coated with a suitable alloy.

1.2.3 All conductors are to be stranded, except for cablesof nominal cross-sectional area 2,5 mm2 and less (providedthat adequate flexibility of the finished cable is assured).

1.2.4 For the minimum nominal cross-sectional areas per-mitted, see Ch 2, Sec 3, [9.10].

1.3 Insulating materials

1.3.1 The materials used for insulation are to comply withIEC Publication 60092-351 and to have the thicknessesspecified for each type of cable in the relevant standard.The maximum permissible rated temperature is specified forthe various materials.

1.3.2 Materials and thicknesses other than those in [1.3.1]will be specially considered by the Society.

1.4 Inner covering, fillers and binders

1.4.1 The cores of a multicore cable are to be laid up. Thespaces between the cores are to be filled so as to obtain anassembly having an essentially circular cross-section. Thefilling may be omitted in multicore cables having a conduc-tor cross-sectional area not exceeding 4 mm2.

When a non-metallic sheath is applied directly over theinner covering or the fillers, it may substitute partially forthe inner covering or fillers.

1.4.2 The materials used, the binders and the thicknesses ofthe inner coverings are generally to be in accordance withIEC Publications of the series 60092-3.., in relation to thetype of cable.

1.5 Protective coverings (armour and sheath)

1.5.1 Metallic armour, if not otherwise protected againstcorrosion, is to be protected by means of a coating of pro-tective paint (see Ch 2, Sec 3, [9.3]).

1.5.2 The paint is to be non-flammable and of adequateviscosity. When dry, it is not to flake off.

1.5.3 The materials and construction used for (metal)armour are to be in accordance with IEC Publication60092-350 and their dimensions are to be those specifiedfor each type of cable in the relevant standard.


Pt C, Ch 2, Sec 9

1.5.4 The materials used for sheaths are to be in accord-ance with IEC Publication 60092-359 and are to have thethicknesses specified for each type of cable in the relevantstandard.The quality of the materials is to be adequate to the servicetemperature of the cable.

1.5.5 Materials other than those in [1.5.3] and [1.5.4] willbe specially considered by the Society.

1.6 Identification

1.6.1 Each cable is to have clear means of identification sothat the manufacturer can be determined.

1.6.2 Fire non propagating cables are to be clearly labelledwith indication of the standard according to which thischaracteristic has been verified and, if applicable, of thecategory to which they correspond.

2 Testing

2.1 Type tests

2.1.1 Type tests are to be in accordance with the relevantIEC 60092-3.. Series Publications and IEC 60332-1, IEC60332-3 Category A, and IEC 60331 where applicable.

2.2 Routine tests

2.2.1 Every length of finished cable is to be subjected to thetests specified in [2.2.2].

2.2.2 The following routine tests are to be carried out:

a) visual inspection

b) check of conductor cross-sectional area by measuringelectrical resistance

c) high voltage test

d) insulation resistance measurement

e) dimensional checks (as necessary).

2.2.3 The manufacturer is to issue a statement providinginformation on the type and characteristics of the cable, aswell as the results of the tests required and the TypeApproval Certificates.

2.2.4 The test procedure is as specified in IEC Publication60092-350.

2.2.5 Where an alternative scheme, e.g. a certified qualityassurance system, is recognised by the Society, attendanceof the Surveyor may not be required.


Pt C, Ch 2, Sec 10

SECTION 10 MISCELLANEOUS EQUIPMENT

1 Switchgear and controlgear, protective devices

1.1 General

1.1.1 Switchgear and controlgear are to comply with IECPublication 60947.

1.1.2 For materials and construction see Ch 2, Sec 2, [4]and Ch 2, Sec 2, [5].

1.2 Circuit-breakers

1.2.1 Power-driven circuit-breakers are to be equippedwith an additional separate drive operated by hand.

1.2.2 Power circuit-breakers with a making capacityexceeding 10 kA are to be equipped with a drive which per-forms the make operation independently of the actuatingforce and speed.

1.2.3 Where the conditions for closing the circuit-breakerare not satisfied (e.g. if the undervoltage trip is not ener-gised), the closing mechanism is not to cause the closing ofthe contacts.

1.2.4 All circuit-breakers rated more than 16 A are to be ofthe trip-free type, i.e. the breaking action initiated by over-current or undervoltage releases is to be fulfilled independ-ently of the position of the manual handle or other closingdevices.

1.3 Protection devices

1.3.1 Short-circuit releases are generally to be independentof energy supplied from circuits other than that to be pro-tected. Tripping due to short-circuit is to be reliable even inthe event of a total loss of voltage in the protected circuit.

1.3.2 Short-circuit releases for generators are to beequipped with reclosing inhibitors and are to be delayed forselective tripping.

1.3.3 Overload releases or relays are to operate reliably atany voltage variation of the supply voltage in the protectedcircuit.

1.3.4 Undervoltage relays or releases are to cause the cir-cuit-breaker to open if the voltage drops to 70%-35% of therated voltage.

1.3.5 Shunt releases are to ensure the disconnection of thecircuit-breaker even when the supply voltage of the releasedrops to 85% of the rated supply voltage.

1.3.6 The reverse power protection device is to respond tothe active power regardless of the power factor, and is tooperate only in the event of reverse power.

1.3.7 Single-phase failure devices in three-phase circuitsare to operate without a time lag.

1.3.8 Insulation monitoring devices are to continuouslymonitor the insulation resistance to earth and trigger analarm should the insulation resistance fall below a predeter-mined value.

The measuring current of such devices is not to exceed 30mA in the event of a total short to earth.

2 Lighting fittings


2.1.1 Lighting fittings are to comply with IEC Publications60598 and 60092-306.

Lighting fittings complying with other standards will be spe-cially considered by the Society.

2.2 Construction

2.2.1 The temperature of terminals for connection of sup-plying cables is not to exceed the maximum conductor tem-perature permitted for the cable (see Ch 2, Sec 3, [9.9]).

Where necessary, luminaires are to be fitted with terminalboxes which are thermally insulated from the light source.

2.2.2 Wires used for internal connections are to be of atemperature class which corresponds to the maximum tem-perature within the luminaire.

2.2.3 The temperature rise of parts of luminaires which arein contact with the support is not to exceed 50°C. The rise isnot to exceed 40°C for parts in contact with flammablematerials.

2.2.4 The temperature rise of surface parts which can easilybe touched in service is not to exceed 15°C.

2.2.5 High-power lights with higher surface temperaturesthan those in [2.2.2] and [2.2.3] are to be adequately pro-tected against accidental contact.

3 Accessories


3.1.1 Accessories are to be constructed in accordance withthe relevant IEC Publications, and in particular with Publi-cation 60092-306.


Pt C, Ch 2, Sec 10

3.2 Construction

3.2.1 Enclosures of accessories are to be of metal havingcharacteristics suitable for the intended use on board, or offlame-retardant insulating material.

3.2.2 Terminals are to be suitable for the connection ofstranded conductors, except in the case of rigid conductorsfor mineral-insulated cables.

4 Plug-and-socket connections


4.1.1 Plug-and-socket connections are to comply with IECPublication 60092-306 and with the following additionalstandards in relation to their use:

• in accommodation spaces, day rooms and servicerooms (up to 16 A, 250 V a.c.): IEC Publication 60083or 60320, as applicable

• for power circuits (up to 250 A, 690 V a.c.): IEC Publica-tion 60309

• for electronic switchgear: IEC Publications, e.g. 60512and 60603

• for refrigerated containers: ISO 1496-2.

5 Heating and cooking appliances


5.1.1 Heating and cooking appliances are to comply withthe relevant IEC Publications (e.g. those of series 60335),with particular attention to IEC 60092-307.

5.2 General

5.2.1 Heating elements are to be enclosed and protectedwith metal or refractory material.

5.2.2 The terminals of the power supply cable are not to besubjected to a higher temperature than that permitted forthe conductor of the connection cable.

5.2.3 The temperature of parts which are to be handled inservice (switch knobs, operating handles and the like) is notto exceed the following values:• 55°C for metal parts• 65°C for vitreous or moulded material.

5.3 Space heaters

5.3.1 The casing or enclosure of heaters is to be sodesigned that clothing or other flammable material cannotbe placed on them.

5.3.2 The temperature of the external surface of space heat-ers is not to exceed 60°C.

5.3.3 Space heaters are to be provided with a temperaturelimiting device without automatic reconnection whichautomatically trips all poles or phases not connected toearth when the temperature exceeds the maximum permis-sible value.

5.4 Cooking appliances

5.4.1 Live parts of cooking appliances are to be protectedsuch that any foods or liquids which boil over or spill do notcause short-circuits or loss of insulation.

5.5 Fuel oil and lube oil heaters

5.5.1 In continuous-flow fuel oil and lube oil heaters, themaximum temperature of the heating elements is to bebelow the boiling point of the oil.

5.5.2 Each oil heater is to be provided with a thermostatmaintaining the oil temperature at the correct level.

5.5.3 In addition to the thermostat in [5.5.2], each oilheater is to be provided with a temperature limiting devicewithout automatic reconnection, and with the sensingdevice installed as close as possible to the heating elementsand permanently submerged in the liquid.

5.6 Water heaters

5.6.1 Water heaters are to be provided with a thermostatand safety temperature limiter.


Pt C, Ch 2, Sec 11

SECTION 11 LOCATION

1 General

1.1 Location

1.1.1 The degree of protection of the enclosures and theenvironmental categories of the equipment are to be appro-priate to the spaces or areas in which they are located; seeCh 2, Sec 3, Tab 2, Ch 2, Sec 3, Tab 3 and Ch 2, Sec 2,[5.2.2].

1.2 Areas with a risk of explosion

1.2.1 Except where the installation of equipment for explo-sive gas atmosphere is provided for by the Rules, electricalequipment is not to be installed where flammable gases orvapours are liable to accumulate; see Ch 2, Sec 3, [10].

2 Main electrical system

2.1 Location in relation to the emergency system

2.1.1 The arrangement of the emergency electrical systemis to be such that a fire or other casualty in spaces contain-ing the emergency source of electrical power, associatedconverting equipment, if any, the emergency switchboardand the emergency lighting switchboard will not renderinoperative the main electric lighting system and the otherprimary essential services.


2.2.1 The main switchboard shall be so placed relative toone main generating station that, as far as is practicable, theintegrity of the normal electrical supply may be affectedonly by a fire or other casualty in one space.

2.2.2 An environmental enclosure for the main switch-board, such as may be provided by a machinery controlroom situated within the main boundaries of the space, isnot to be considered as separating switchboards from gen-erators.

2.2.3 The main generating station is to be situated withinthe machinery space, i.e. within the extreme main trans-verse watertight bulkheads.

2.2.4 Any bulkhead between the extreme main transversewatertight bulkheads is not regarded as separating theequipment in the main generating station provided thatthere is access between the spaces.

2.2.5 The main switchboard is to be located as close aspracticable to the main generating station, within the samemachinery space and the same vertical and horizontal A60fire boundaries.

2.2.6 Where essential services for steering and propulsionare supplied from section boards, these and any transform-ers, convertors and similar appliances constituting an essen-tial part of the electrical supply system are also to satisfy theabove provisions.

2.2.7 A non-required subdivision bulkhead, with sufficientaccess, located between the switchboard and generators, orbetween two or more generators, is not to be considered asseparating the equipment.

3 Emergency electrical system

3.1 Spaces for the emergency source

3.1.1 The emergency source of electrical power, associatedtransforming equipment, if any, transitional source of emer-gency power, emergency switchboard and emergency light-ing switchboard shall be located above the uppermostcontinuous deck and shall be readily accessible from theopen deck.

They shall not be located forward of the collision bulkhead.

3.1.2 The spaces containing the emergency source of elec-trical power, associated transforming equipment, if any, thetransitional source of emergency electrical power and theemergency switchboard are not to be contiguous to theboundaries of machinery spaces of Category A or thosespaces containing the main source of electrical power, asso-ciated transforming equipment, if any, and the main switch-board.

Where this is not practicable, the contiguous boundariesare to be Class A60.

3.2 Location in relation to the main electrical system

3.2.1 The location of the emergency source of electricalpower, associated transforming equipment, if any, the transi-tional source of emergency power, the emergency switch-board and the emergency lighting switchboard in relation tothe main source of electrical power, associated transformingequipment, if any, and the main switchboard shall be suchas to ensure to the satisfaction of the Society that a fire orother casualty in the space containing the main source ofelectrical power, associated transforming equipment, if any,and the main switchboard or in any machinery space ofCategory A will not interfere with the supply, control anddistribution of emergency electrical power.


Pt C, Ch 2, Sec 11

3.2.2 The arrangement of the main electrical system is tobe such that a fire or other casualty in spaces containing themain source of electrical power, associated convertingequipment, if any, the main switchboard and the main light-ing switchboard will not render inoperative the emergencyelectric lighting system and the other emergency servicesother than those located within the spaces where the fire orcasualty has occurred.


3.3.1 The emergency switchboard shall be installed as nearas is practicable to the emergency source of electricalpower.

3.3.2 Where the emergency source of electrical power is agenerator, the emergency switchboard shall be located inthe same space unless the operation of the emergencyswitchboard would thereby be impaired.

3.4 Emergency battery

3.4.1 No accumulator battery fitted in accordance with theprovisions of Ch 2, Sec 3, [2.3] shall be installed in the samespace as the emergency switchboard.

3.4.2 For ships not subject to Solas, accumulator batteriesfitted in accordance with the provisions of Ch 2, Sec 3,[2.3] and connected to a charging device of power of 2 kWor less may be accepted in the same space as the emer-gency switchboard but outside the emergency switchboardto the satisfaction of the Society.

4 Distribution boards

4.1 Distribution boards for cargo spaces and similar spaces

4.1.1 Distribution boards containing multipole switches forthe control of power and lighting circuits in bunkers andcargo spaces are to be situated outside such spaces.

4.2 Distribution board for navigation lights

4.2.1 The distribution board for navigation lights is to beplaced in an accessible position on the bridge.

5 Cable runs

5.1 General

5.1.1 Cable runs are to be selected so as to be as far aspracticable accessible, with the exception of single cables,situated behind walls or ceilings constructed of incombusti-ble materials, supplying lighting fittings and socket-outletsin accommodation spaces, or cables enclosed in pipes orconduits for installation purposes.

5.1.2 Cable runs are to be selected so as to avoid actionfrom condensed moisture and from dripping of liquids.

5.1.3 Connection and draw boxes are to be accessible.

5.1.4 Cables are generally not to be installed across expan-sion joints.

Where this is unavoidable, however, a loop of cable oflength proportional to the expansion of the joint is to beprovided (see Ch 2, Sec 12, [7.2.2]).

5.2 Location of cables in relation to the risk of fire and overheating

5.2.1 Cables and wiring serving essential or emergencypower, lighting, internal communications or signals are, sofar as is practicable, to be routed clear of galleys, laundries,machinery spaces of Category A and their casings and otherhigh fire risk areas, except for supplying equipment in thosespaces.

5.2.2 When it is essential that a circuit functions for sometime during a fire and it is unavoidable to carry the cable forsuch a circuit through a high fire risk area (e.g. cables con-necting fire pumps to the emergency switchboard), thecable is to be of a fire-resistant type or adequately protectedagainst direct exposure to fire.

5.2.3 Main cable runs (see [5.2.3], Note 1) and cables forthe supply and control of essential services are, as far as ispracticable, to be kept away from machinery parts havingan increased fire risk (see [5.2.3], Note 2) unless:

• the cables have to be connected to the subject equip-ment

• the cables are protected by a steel bulkhead or deck, or

• the cables in that area are of the fire-resisting type.

Note 1: Main cable runs are for example:

• cable runs from generators and propulsion motors to main andemergency switchboards

• cable runs directly above or below main and emergencyswitchboards, centralised motor starter panels, section boardsand centralised control panels for propulsion and essentialauxiliaries.

Note 2: Machinery, machinery parts or equipment handling com-bustibles are considered to present an increased fire risk.

5.2.4 Cables and wiring serving essential or emergencypower, lighting, internal communications or signals are tobe arranged, as far as practicable, in such a manner as topreclude their being rendered unserviceable by heating ofthe bulkheads that may be caused by a fire in an adjacentspace.

5.2.5 Cables are to be arranged as remote as possible fromsources of heat such as hot pipes, resistors, etc. Whereinstallation of cables near heat sources cannot be avoided,and where there is consequently a risk of damage to thecables by heat, suitable shields are to be installed, or otherprecautions to avoid overheating are to be taken, for exam-ple use of ventilation, heat insulation materials or specialheat-resisting cables.


Pt C, Ch 2, Sec 11

5.3 Location of cables in relation to electro-magnetic interference

5.3.1 For the installation of cables in the vicinity of radioequipment or of cables belonging to electronic control andmonitoring systems, steps are to be taken in order to limitthe effects of unwanted electromagnetic interference (seeCh 3, Sec 5).

5.4 Services with a duplicate feeder

5.4.1 In the case of essential services requiring a duplicatesupply (e.g. steering gear circuits), the supply and associ-ated control cables are to follow different routes which areto be as far apart as practicable, separated both verticallyand horizontally.

5.5 Emergency circuits

5.5.1 Cables supplying emergency circuits are not to runthrough spaces containing the main source of electricalpower, associated transforming equipment, if any, the mainswitchboard and the main lighting switchboard, except forcables supplying emergency equipment located within suchspaces (see [3.2.2]).

5.6 Electrical distribution in passenger ships

5.6.1 For the electrical distribution in passenger ships, seePt D, Ch 11, Sec 5, [1.2].

6 Storage batteries

6.1 General

6.1.1 Batteries are to be located where they are notexposed to excessive heat, extreme cold, spray, steam orother conditions which would impair performance or accel-erate deterioration. They are to be installed in such a waythat no damage may be caused to surrounding appliancesby the vapours generated.

6.1.2 Storage batteries are to be suitably housed, and com-partments (rooms, lockers or boxes) used primarily for theiraccommodation are to be properly constructed and effi-ciently ventilated so as to prevent accumulation of flamma-ble gas.

6.1.3 Starter batteries are to be located as close as practica-ble to the engine or engines served.

6.1.4 Accumulator batteries shall not be located in sleepingquarters except where hermetically sealed to the satisfactionof the Society.

6.1.5 Lead-acid batteries and alkaline batteries are not tobe installed in the same compartment (room, locker, box),unless of valve-regulated sealed type.

6.2 Large vented batteries

6.2.1 Batteries connected to a charging device of powerexceeding 2 kW, calculated from the maximum obtainablecharging current and the nominal voltage of the battery(hereafter referred to as "large batteries") are to be installedin a room assigned to batteries only.

Where this is not possible, they may be arranged in a suita-ble locker on deck.

6.2.2 Rooms assigned to large batteries are to be providedwith mechanical exhaust ventilation.

Natural ventilation may be employed for boxes located onopen deck.

6.2.3 The provisions of [6.2.1] and [6.2.2] also apply toseveral batteries connected to charging devices of totalpower exceeding 2 kW calculated for each one as stated in[6.2.1].

6.3 Moderate vented batteries

6.3.1 Batteries connected to a charging device of powerbetween 0,2 kW and 2 kW calculated as stated in [6.2.1](hereafter referred to as "moderate batteries") are to bearranged in the same manner as large batteries or placed ina box or locker in suitable locations such as machineryspaces, storerooms or similar spaces. In machinery spacesand similar well-ventilated compartments, these batteriesmay be installed without a box or locker provided they areprotected from falling objects, dripping water and conden-sation where necessary.

6.3.2 Rooms, lockers or boxes assigned to moderate batter-ies are to be provided with natural ventilation or mechani-cal exhaust ventilation, except for batteries installedwithout a box or locker (located open) in well-ventilatedspaces.

6.3.3 The provisions of [6.3.1] and [6.3.2] also apply toseveral batteries connected to charging devices of totalpower between 0,2 kW and 2 kW calculated for each oneas stated in [6.2.1].

6.4 Small vented batteries

6.4.1 Batteries connected to a charging device of powerless than 0,2 kW calculated as stated in [6.2.1] (hereafterreferred to as "small batteries") are to be arranged in thesame manner as moderate or large batteries, or without abox or locker, provided they are protected from fallingobjects, or in a box in a ventilated area.

6.4.2 Boxes for small batteries may be ventilated only bymeans of openings near the top to permit escape of gas.

6.5 Ventilation

6.5.1 The ventilation of battery compartments is to be inde-pendent of ventilation systems for other spaces.


Pt C, Ch 2, Sec 11

6.5.2 The quantity of air expelled (by natural or forced ven-tilation) for compartments containing vented type batteriesis to be at least equal to:

Q = 110 I n

where:

Q : Quantity of air expelled, in litres per hour

I : Maximum current delivered by the chargingequipment during gas formation, but not lessthan one quarter of the maximum obtainablecharging current in amperes

n : Number of cells in series.

6.5.3 The quantity of air expelled (by natural or forced ven-tilation) for compartments containing valve-regulatedsealed batteries is to be at least 25% of that given in [6.5.2].

6.5.4 Ducts are to be made of a corrosion-resisting materialor their interior surfaces are to be painted with corrosion-resistant paint.

6.5.5 Adequate air inlets (whether connected to ducts ornot) are to be provided near the floor of battery rooms or thebottom of lockers or boxes (except for that of small batter-ies).

Air inlet may be from the open air or from another space(for example from machinery spaces).

6.5.6 Exhaust ducts of natural ventilation systems:

a) are to be run directly from the top of the compartmentto the open air above (they may terminate in the open orin well-ventilated spaces)

b) are to terminate not less than 90 cm above the top of thebattery compartment

c) are to have no part more than 45° from the vertical

d) are not to contain appliances (for example for barringflames) which may impede the free passage of air or gasmixtures.

Where natural ventilation is impracticable or insufficient,mechanical exhaust ventilation is to be provided.

6.5.7 In mechanical exhaust ventilation systems:

a) electric motors are to be outside the exhaust ducts andbattery compartment and are to be of safe type ifinstalled within 3 m from the exhaust of the ventilationduct

b) fans are to be so constructed and of a material such as torender sparking impossible in the event of the impellertouching the fan casing

c) steel or aluminium impellers are not to be used

d) the system is to be interlocked with the charging deviceso that the battery cannot be charged without ventila-tion (trickle charge may be maintained)

e) a temperature sensor is to be located in the battery com-partment to monitor the correct behaviour of the batteryin cases where the battery element is sensitive to tem-perature.

6.5.8 For natural ventilation systems for deck boxes:

a) holes for air inlet are to be provided on at least twoopposite sides of the box

b) the exhaust duct is to be of ample dimensions

c) the duct is to terminate at least 1,25 m above the box ina goose-neck or mushroom-head or the equivalent

d) the degree of protection is to be in accordance with Ch2, Sec 3, Tab 2.


Pt C, Ch 2, Sec 12

SECTION 12 INSTALLATION

1 General

1.1 Protection against injury or damage caused by electrical equipment

1.1.1 All electrical equipment is to be so installed as not tocause injury when handled or touched in the normal man-ner.

1.1.2 All electrical equipment is to be installed in such away that live parts cannot be inadvertently touched, unlesssupplied at a safety voltage.

1.1.3 For protective earthing as a precaution against indi-rect contact, see [2].

1.1.4 Equipment is to be installed so as not to cause, or atleast so as to reduce to a minimum, electromagnetic inter-ference.

1.2 Protection against damage to electrical equipment

1.2.1 Electrical equipment is to be so placed that as far aspracticable it is not exposed to risk of damage from water,steam, oil or oil vapours.

1.2.2 The air supply for internal ventilation of electricalequipment is to be as clean and dry as practicable; coolingair for internal ventilation is not to be drawn from below thefloor plates in engine and/or boiler rooms.

1.2.3 Equipment is to be so mounted that its enclosingarrangements and the functioning of the built-in equipmentwill not be affected by distortions, vibrations and move-ments of the ship’s structure or by other damage liable tooccur.

1.2.4 If electrical fittings, not of aluminium, are attached toaluminium, suitable provision is to be made to prevent gal-vanic corrosion.

1.3 Accessibility

1.3.1 Equipment is to be so installed that sufficient space isavailable for inspection and maintenance as required for allits parts (see [6.1.3]).

1.4 Electrical equipment in environmentally controlled spaces

1.4.1 Where electrical equipment is installed within envi-ronmentally controlled space the ambient temperature forwhich the equipment is to be suitable may be reduced from45°C and maintained at a value not less than 35°C pro-vided:

a) the equipment is not for use for emergency services

b) temperature control is achieved by at least two coolingunits so arranged that in the event of loss of one coolingunit, for any reason, the remaining unit(s) is capable ofsatisfactorily maintaining the design temperature

c) the equipment is able to be initially set to work safetywithin a 45°C ambient temperature until such a timethat the lesser ambient temperature may be achieved;the cooling equipment is to be rated for a 45°C ambienttemperature

d) audible and visual alarms are provided, at a continuallymanned control station, to indicate any malfunction ofthe cooling units.

1.4.2 In accepting a lesser ambient temperature than 45°C,it is to be ensured that electrical cables for their entirelength are adequately rated for the maximum ambient tem-perature to which they are exposed along their length.

2 Earthing of non-current carrying parts

2.1 Parts which are to be earthed

2.1.1 Exposed metal parts of both fixed and portable elec-trical machines or equipment which are not intended to belive but which are liable under fault conditions to becomelive and similar metal parts inside non-metallic enclosuresare to be earthed unless the machines or equipment are:

a) supplied at a voltage not exceeding 50 V direct currentor 50 V, root mean square between conductors,achieved without the use of auto-transformers (safetyvoltage); or

b) supplied at a voltage not exceeding 250 V by safety iso-lating transformers supplying one consuming deviceonly; or

c) constructed in accordance with the principle of doubleinsulation.

2.1.2 To minimise shock from high frequency voltageinduced by the radio transmitter, handles, handrails andother metal elements on the bridge or upper decks are to bein electrical connection with the hull or superstructures.

2.2 Methods of earthing

2.2.1 Metal frames or enclosures of apparatus and electri-cal machinery may be fixed to, and in metallic contactwith, the ship’s structure, provided that the surfaces in con-tact are clean and free from rust, scale or paint wheninstalled and are firmly bolted together.


Pt C, Ch 2, Sec 12

2.2.2 For metal frames or enclosures which are not earthedas specified in [2.2.1], earthing connections complyingwith [2.3] and [2.4] are to be used.

2.2.3 For requirements regarding the earthing of coveringsof cables and the mechanical protection of cables, see[7.11] and [7.12].

2.3 Earthing connections

2.3.1 Every earthing connection is to be of copper or othercorrosion-resistant material and is to be securely installedand protected, where necessary, against damage and elec-trolytic corrosion.

2.3.2 The nominal cross-sectional area of each copperearthing connection is to be not less than that required inTab 1.

Earthing connections of other metals are to have conduc-tance at least equal to that specified for a copper earthingconnection.

2.3.3 Metal parts of portable appliances are to be earthed,where required (see [2.1.1]), by means of an earth-continu-ity conductor in the flexible supply cable or cord, whichhas the cross-sectional area specified in Tab 1 and which isearthed, for example, through the associated plug andsocket.

2.3.4 In no circumstances is the lead sheathing or armourof cables to be relied upon as the sole means of earthing.

2.4 Connection to the ship’s structure

2.4.1 Every connection of an earth-continuity conductor orearthing lead to the ship’s structure is to be secured bymeans of a screw of brass or other corrosion-resistant mate-rial of diameter not less than 6 mm.

2.4.2 Such earthing connection is not to be used for otherpurposes.

2.4.3 The connection described in [2.4.1] is to be locatedin an accessible position where it may readily be checked.

2.5 Earthed distribution systems

2.5.1 The system earthing of earthed distribution systems isto be effected by means independent of any earthingarrangements of non-current carrying parts and is to be con-nected to the hull at one point only.

2.5.2 In an earthed distribution system in which the earth-ing connection does not normally carry current, this con-nection is to conform with the requirements of [2.3], exceptthat the lower limit of 70 mm2 does not apply (see Tab 1).

2.5.3 In a distribution system with hull return, the systemearthing connection is to have at least the same cross-sec-tional area as the feeder lines.

2.5.4 The earthing connection is to be in an accessibleposition where it may readily be inspected and discon-nected for insulation testing.

Table 1 : Cross-sectional area of earth-continuity conductors and earthing connections

Type of earthing connectionCross-sectional area of associated currentcarrying conductor

Minimum cross-sectional area of copper earthing connection

1 Earth-continuityconductor in flexible cable or flexible cord

any Same as current carrying conductor up to and including 16 mm2 and one half above 16 mm2 but at least 16 mm2

2 Earth-continuityconductorincorporated in fixed cable

any a) for cables having an insulated earth-continuity conductor• a cross-section equal to the main conductors up to and including

16 mm2, but minimum 1,5 mm2

• a cross-section not less than 50% of the cross-section of the main conductor when the latter is more than 16 mm2, but at least 16 mm2

b) for cables with a bare earth wire in direct contact with the lead sheath

Cross-section of main conductor,in mm2

Earthing connection,in mm2

1 ÷ 2,54 ÷ 6

11,5

3 Separate fixed earthing conductor

≤ 2,5 mm2 Same as current carrying conductor subject to minimum of 1,5 mm2 for stranded earthing connection or 2,5 mm2 for unstranded earthing connection

> 2,5 mm2 but≤ 120 mm2

One half the cross-sectional area of the current carrying conductor, subjected to a minimum of 4 mm2

> 120 mm2 70 mm2


Pt C, Ch 2, Sec 12

2.6 Aluminium superstructures

2.6.1 When aluminium superstructures are insulated fromthe steel hull to prevent electrolytic corrosion, they are tobe secured to the hull by means of a separate bonding con-nection.

2.6.2 The connections are to be adequately close togetherand are to have a resistance less than 0,1 Ω.

2.6.3 The connections are to be located where they mayreadily be inspected.

3 Rotating machines

3.1

3.1.1 Every rotating machine is preferably to be installedwith the shaft in the fore-and-aft direction. Where a rotatingmachine of 100 kW and over is installed athwartship, orvertically, it is to be ensured that the design of the bearingsand the arrangements for lubrication are satisfactory towithstand the rolling specified in Ch 2, Sec 2, Tab 4.

4 Semiconductor convertors

4.1 Semiconductor power convertors

4.1.1 Naturally air-cooled semiconductor convertors are tobe installed such that the circulation of air to and from thestacks or enclosures is not impeded and that the tempera-ture of the cooling inlet air to convertor stacks does notexceed the ambient temperature for which the stacks arespecified.

5 Vented type storage batteries

5.1 General

5.1.1 Batteries are to be arranged so that each cell or crateof cells is accessible from the top and at least one side topermit replacement and periodical maintenance.

5.1.2 Cells or crates are to be carried on insulating supportsof material non-absorbent to the electrolyte (e.g. treatedwood).

5.1.3 Cells are to be securely chocked by means of insulat-ing material non-absorbent to the electrolyte, e.g. strips oftreated wood. Special mechanical precautions are to betaken to prevent the emergency battery from being dam-aged by the shock due to a collision.

5.1.4 Provision is to be made for the free circulation of air.

5.2 Protection against corrosion

5.2.1 The interior of battery compartments (rooms, lockers,boxes) including all metal parts subject to the electrolyte isto be protected against the deteriorating effect of the latterby electrolyte-resistant coating or other equivalent means,unless corrosion-resistant materials are used.

5.2.2 Interior surfaces of metal shelves for battery cells,whether or not grouped in crates or trays, are to be pro-tected by a lining of electrolyte-resistant material, watertightand carried up to at least 75 mm on all sides. In particular,linings are to have a minimum thickness of 1,5 mm, if oflead sheet for lead-acid batteries, and of 0,8 mm, if of steelfor alkaline batteries.

Alternatively, the floor of the room or locker is to be lined asspecified above to a height of at least 150 mm.

5.2.3 Battery boxes are to be lined in accordance with[5.2.2] to a height of at least 75 mm.

6 Switchgear and controlgear assemblies


6.1.1 The main switchboard is to be so arranged as to giveeasy access as may be needed to apparatus and equipment,without danger to personnel.

6.1.2 An unobstructed space is to be left in front of theswitchboard wide enough to allow access for operation;such width is generally about 1 metre.

When withdrawable equipment is contained in the switch-board, the width of the space is to be not less than 0,5 mwhen the equipment is fully withdrawn.

Reduced widths may be considered for small ships.

6.1.3 Where necessary, an unobstructed space is to be pro-vided at the rear of the switchboard ample to permit main-tenance; in general, the width of this passage is to be notless than 0,6 m, except that this may be reduced to 0,5 m inway of stiffeners and frames, and the height sufficient for theoperation foreseen.

6.1.4 Where the switchboard is open at the rear, the rearspace in [6.1.3] is to form a locked space provided at eachend with an access door. The required IP protection for thecorresponding location is to be fulfilled.

6.1.5 If necessary, the clear height above the switchboardspecified by the manufacturer is to be maintained for pres-sure relief in the event of a short-circuit.

6.1.6 When the voltage exceeds the safety voltage, non-conducting mats or gratings are to be provided at the frontand rear of the switchboard as necessary.

6.1.7 Piping and conduits are not to be installed directlyabove or in the vicinity of switchboards.

Where this is unavoidable, pipes and conduits are to havewelded joints only or to be provided with protection againstspray from steam or pressurised liquids or dripping.


6.2.1 For the installation of the emergency switchboard, thesame requirements apply as given in [6.1] for the installa-tion of the main switchboard.


Pt C, Ch 2, Sec 12

6.3 Section boards and distribution boards

6.3.1 For the installation of section and distribution boards,the same requirements apply, as far as applicable, as givenin [6.1] for the installation of the main switchboard.

7 Cables

7.1 General

7.1.1 Cables having insulating materials with differentmaximum permissible conductor temperatures are not to bebunched together.

Where this is not practicable, the cables are to be soinstalled that no cable reaches a temperature higher than itsrating.

7.1.2 Cables having a protective covering which may dam-age the covering of more vulnerable cables are not to bebunched with the latter.

7.1.3 Cables having a bare metallic sheath (e.g. of copper)or braid or armour are to be installed in such a way that gal-vanic corrosion by contact with other metals is prevented.

7.1.4 All cables and wiring external to equipment are to beso installed as not to impair their original flame-retardingproperties.

To this end, the following methods may be used:

a) the use of cables which have been tested in accordancewith IEC Publication 332-3 Category A or an equivalenttest procedure for cables installed in bunches, or

b) the use of fire stops having at least B0 penetrations fittedas follows (see Fig 1, Fig 2, Fig 3 and Fig 4):

• cable entries at the main and emergency switch-board

• where cables enter engine control rooms

• cable entries at centralised control panels for pro-pulsion machinery and essential auxiliaries

• at each end of totally enclosed cable trunks

• at every second deck or approximately 6 metres forverticals runs and every 14 metres for horizontalruns in enclosed and semi-enclosed spaces

• at the boundaries of the spaces in cargo areas.

Figure 1 : Totally enclosed trunks

Figure 2 : Non-totally enclosed trunks, vertical

BO Penetration

BO Penetration

Fire stop with steel plate andBO penetration

2a

2a

2a

a

a

6 m

A

B


Pt C, Ch 2, Sec 12

Figure 3 : Non-totally enclosed trunks, horizontal

c) the use of fire protection coating applied to at least 1metre in every 14 metres on horizontal cable runs andover the entire length of vertical cable runs for cablesinstalled in enclosed and semi-enclosed spaces.

The cable penetrations are to be installed in steel plates ofat least 3 mm thickness extending all around to twice thelargest dimension of the cable run for vertical runs and oncefor horizontal runs, but need not extend through ceilings,decks, bulkheads or solid sides of trunks. These precautionsapply in particular to bunches of 5 or more cables in areaswith a high fire risk (such as Category A machinery spaces,galleys etc.) and to bunches of more than 10 cables in otherareas.

7.2 Radius of bend

7.2.1 The internal radius of bend for the installation ofcables is to be chosen according to the type of cable as rec-ommended by the manufacturer.

Its value is generally to be not less than the figure given inTab 2.

7.2.2 Where the installation of cables across expansionjoints is unavoidable, the minimum internal radius of theloop at the end of the travel of the expansion joint is to benot less than 12 times the external diameter of the cable.

7.3 Fixing of cables

7.3.1 Cables shall be installed and supported in such amanner as to avoid chafing or other damage.

7.3.2 The supports (tray plates, separate support brackets orhanger ladders) and the corresponding accessories are to beof robust construction and of corrosion-resistant material orsuitably treated before erection to resist corrosion.

When cables are installed directly on aluminium structures,fixing devices of aluminium or suitably treated steel are tobe used.

For mineral-insulated cables with copper sheath, fixingdevices in contact with the sheath are to be of copper alloy.

Table 2 : Bending radii

Steel plate

Penetration Penetration

14 m

BO BO

DECK DECK

a Steel plate

a 1a

Cable construction Overall diameter of cable (D)

Minimum internal radius of bendInsulation Outer covering

Thermoplastic or thermosetting with circular copper conductors

Unarmouredor unbraided

≤ 25 mm 4 D

> 25 mm 6 D

Metal braid screened or armoured Any 6 D

Metal wire armouredMetal tape armoured or metal-sheathed

Any 6 D

Composite polyester/metal laminate tape screened units or collective tape screening

Any 8 D

Thermoplastic or thermosetting with shaped copper conductors

Any Any 8 D


Pt C, Ch 2, Sec 12

Figure 4 : Open cables runs

Coa

ting

Ent

ire L

engt

h

1a

2a

2aa2a2a

1m

CoatingCoating

1m

14m

1a

BO Penetration

Steel plate

FIRE STOP1a

a1a

14m

Horizontal

Steel plate

FIRE STOP

6m

FIRE STOP

or

Vertical

BO Penetration


Pt C, Ch 2, Sec 12

7.3.3 With the exception of cables installed in pipes, con-duits, trunkings or special casings, cables are to be fixed bymeans of clips, saddles or straps of suitable material, inorder to tighten the cables without their coverings beingdamaged.

7.3.4 Cable clips or straps made from a material other thanmetal are to be manufactured of a flame-retardant material.

7.3.5 The distances between fastenings and between sup-ports are to be suitably chosen according to the type andnumber of cables and the probability of vibration.

7.3.6 When cables are fixed by means of clips or strapsmade from a material other than metal and these cables arenot laid on top of horizontal cable supports (e.g. in the caseof vertical installation), suitable metal clips or saddlesspaced not more than 1 metre apart are to be used in addi-tion in order to prevent the release of cables during a fire.

7.3.7 Suspended cables of fire-resisting type are to be fixedby means of steel straps spaced not more than 500 mmapart.

7.4 Mechanical protection

7.4.1 Cables exposed to risk of mechanical damage are tobe protected by metal casing, profiles or grids or enclosedin metal pipes or conduits, unless the cable covering (e.g.armour or sheath) provides adequate mechanical protec-tion.

7.4.2 In situations where there would be an exceptionalrisk of mechanical damage, e.g. in holds, storage spaces,cargo spaces, etc., cables are to be protected by metal cas-ing, trunkings or conduits, even when armoured, if theship’s structure or attached parts do not afford sufficient pro-tection for the cables.

7.4.3 For the protection of cables passing through decks,see [7.5.3].

7.4.4 Metal casing used for mechanical protection ofcables is to be effectively protected against corrosion.

7.5 Penetrations of bulkheads and decks

7.5.1 If cables have to pass without adequate supportthrough non-watertight bulkheads and generally throughholes drilled in sheets of structural steel, these holes are tobe fitted with glands or bushings of suitable material.

7.5.2 If cables have to pass through a watertight bulkheador deck, the penetration is to be effected in a watertightmanner.

Either suitable individual watertight glands for single cablesor boxes containing several cables and filled with a flame-retardant packing may be used for this purpose.

Whichever type of penetration is used, the watertight integ-rity of the bulkheads or deck is to be maintained.

7.5.3 Cables passing through decks and continuing verti-cally are to be protected against mechanical damage to aheight of about 200 mm above the deck.

7.5.4 Where cables pass through bulkheads or decks sepa-rating areas with a risk of explosion, arrangements are to besuch that hazardous gas or dust cannot penetrate throughopenings for the passage of cables into other areas.

7.5.5 Where cables pass through a bulkhead or deck whichis required to have some degree of fire integrity, penetrationis to be so effected as to ensure that the required degree offire integrity is not impaired.

7.6 Expansion joints

7.6.1 If there is reason to fear that a tray plate, pipe or con-duit may break because of the motion of the ship, differentload conditions and temperature variations, appropriateexpansion joints are to be provided.

This may apply in particular in the case of cable runs on theweather deck.

7.7 Cables in closed pipes or conduits

7.7.1 Closed pipes or conduits are to have such internaldimensions and radius of bend as will permit the easy draw-ing in and out of the cables which they are to contain; theinternal radius of bend is to be not less than that permittedfor cables and, for pipes exceeding 63 mm external diame-ter, not less than twice the external diameter of the pipewhere this value is greater.

7.7.2 Closed pipes and conduits are to be suitably smoothon the interior and are to have their ends shaped or bushedin such a way as not to damage the cable covering.

7.7.3 The space factor (ratio of the sum of the cross-sec-tional areas corresponding to the external diameters of thecables to the internal cross-sectional areas of the pipe orconduit) is to be not greater than 0,4.

7.7.4 If necessary, openings are to be provided at the high-est and lowest points so as to permit air circulation andensure that the heat from the cables can be dissipated, andto obviate the possibility of water accumulating at any partof the pipe or conduit.

7.7.5 Vertical trunking for electrical cables is to be so con-structed as not to jeopardise the required passive fire pro-tection between the spaces.

7.7.6 Metal pipes or conduits are to be protected againstcorrosion.

7.7.7 Non-metallic pipes or conduits are to be flame-retar-dant.

7.8 Cables in casings or trunking and conduits with removable covers

7.8.1 Covers are to be removable and when they are open,cables are to be accessible.

7.8.2 Materials used are to comply with [7.7.6] and [7.7.7].


Pt C, Ch 2, Sec 12

7.8.3 If the fixing of covers is by means of screws, the latterare to be of non-rusting material and arranged so as not todamage the cables.

7.8.4 Means are to be provided to ensure that the heat fromthe cables can be dissipated and water accumulation isavoided (see [7.7.4]).

7.9 Cable ends

7.9.1 Terminations in all conductors are to be so made asto retain the original electrical, mechanical, flame-retardingproperties of the cable.

7.9.2 Where mechanical clamps are not used, the ends ofall conductors having a cross-sectional area greater than 4mm2 are to be fitted with soldering sockets or compression-type sockets of sufficient size to contain all the strands ofthe conductor.

7.9.3 Cables not having a moisture-resistant insulation (e.g.mineral-insulated) are to have their ends effectively sealedagainst ingress of moisture.

7.10 Joints and tappings (branch circuit)

7.10.1 Cable runs are normally not to include joints.Where absolutely necessary, cable joints are to be carriedout by a junction method with rebuilding of the insulationand protective coverings.

7.10.2 Joints in all conductors are to be so made as toretain the original electrical (continuity and isolation),mechanical (strength and protection), flame-retarding and,where necessary, fire-resisting properties of the cable.

7.10.3 Tappings (branch circuits) are to be made via suit-able connections or in suitable boxes of such design thatthe conductors remain adequately insulated and protectedfrom atmospheric action and are fitted with terminals orbusbars of dimensions appropriate to the current rating.

7.10.4 Cables for safety voltages are not to terminate in thesame connection boxes as cable for higher voltages unlessseparated by suitable means.

7.11 Earthing and continuity of metal coverings of cables

7.11.1 All metal coverings of cables are to be electricallyconnected to the metal hull of the ship.

7.11.2 Metal coverings are generally to be earthed at bothends of the cable, except for [7.11.3] and [7.11.4].

7.11.3 Single-point earthing is admitted for final sub-cir-cuits (at the supply end), except for those circuits located inareas with a risk of explosion.

7.11.4 Earthing is to be at one end only in those installa-tions (mineral-insulated cables, intrinsically safe circuits,control circuits (see Ch 3, Sec 5), etc.) where it is requiredfor technical or safety reasons.

7.11.5 Metal coverings of single-core a.c. cables and spe-cial d.c. cables with high "ripple" content (e.g. for thyristorequipment) are to be earthed at one point only (e.g. at themid-point).

7.11.6 The electrical continuity of all metal coverings ofcables throughout the length of the latter, particularly atjoints and tappings, is to be ensured.

7.11.7 The metal covering of cables may be earthed bymeans of glands intended for the purpose and so designedas to ensure an effective earth connection.

The glands are to be firmly attached to, and in effectiveelectrical contact with, a metal structure earthed in accor-dance with these requirements.

7.11.8 The metal covering of cables may also be earthed bymeans of clamps or clips of corrosion-resistant materialmaking effective contact with the covering and earthedmetal.

7.12 Earthing and continuity of metal pipes, conduits and trunking or casings

7.12.1 Metal casings, pipes, conduits and trunking are tobe effectively earthed.

7.12.2 Pipes or conduits may be earthed by being screwedinto a metal enclosure, or by nuts on both sides of the wallof a metallic enclosure, provided the surfaces in contact areclean and free from rust, scale or paint and that the enclo-sure is in accordance with these requirements on earthing.

The connection is to be painted immediately after assemblyin order to inhibit corrosion.

7.12.3 Pipes and conduits may be earthed by means ofclamps or clips of corrosion-resistant metal making effectivecontact with the earthed metal.

7.12.4 Pipes, conduits or trunking together with connec-tion boxes of metallic material are to be electrically contin-uous.

7.12.5 All joints in metal pipes and conduits used for earthcontinuity are to be soundly made and protected, wherenecessary, against corrosion.

7.12.6 Individual short lengths of pipes or conduits neednot be earthed.

7.12.7 The connections to earth are to have a resistanceless than 0,1 Ω.

7.13 Precautions for single-core cables for a.c.

7.13.1 For the earthing of metal coverings see [7.11.5].

7.13.2 Where it is necessary to use single-core cables foralternating current circuits rated in excess of 20 A, therequirements of [7.13.3] to [7.13.7] are to be compliedwith.


Pt C, Ch 2, Sec 12

7.13.3 Conductors belonging to the same circuit are to becontained within the same pipe, conduit or trunking, unlessthis is of non-magnetic material.

7.13.4 Cable clips are to include cables of all phases of acircuit unless the clips are of non-magnetic material.

7.13.5 In the installation of two, three or four single-corecables forming respectively single-phase circuits, three-phase circuits, or three-phase and neutral circuits, the cablesare to be in contact with one another, as far as possible. Inany event, the distance between the external covering of twoadjacent cables is to be not greater than one diameter.

7.13.6 When single-core cables having a current ratinggreater than 250 A are installed near a steel bulkhead, theclearance between the cables and the bulkhead is to be atleast 50 mm, unless the cables belonging to the same circuitare installed in trefoil twisted formation.

7.13.7 Magnetic material is not to be used between single-core cables of a group. Where cables pass through steelplates, all the conductors of the same circuit are to passthrough a plate or gland, so made that there is no magneticmaterial between the cables, and the clearance between thecables and the magnetic material is to be no less than75 mm, unless the cables belonging to the same circuit areinstalled in trefoil twisted formation.

7.14 Cables in refrigerated spaces

7.14.1 For the types of cables permitted in refrigeratedspaces, see Ch 2, Sec 3, [9.4].

7.14.2 Power cables installed in refrigerated spaces are notto be covered by thermal insulation. Moreover, such cablesare not to be placed directly on the face of the refrigeratedspace unless they have a thermoplastic or elastomericextruded sheath.

7.14.3 Power cables entering a refrigerated space are topass through the walls and thermal insulation at rightangles, in tubes sealed at each end and protected againstoxidation.

7.15 Cables in areas with a risk of explosion

7.15.1 For the types of cables permitted in areas with a riskof explosion, see Ch 2, Sec 3, [10.2].

7.15.2 For penetration of bulkheads or decks separatingareas with a risk of explosion, see [7.5.4].

7.15.3 Cables of intrinsically safe circuits are to be sepa-rated from the cables of all other circuits (minimum50 mm).

7.16 Cables and apparatus for services required to be operable under fire conditions

7.16.1 Cables and apparatus for services required to beoperable under fire conditions including their power sup-plies are to be so arranged that the loss of these services is

minimized due to a localized fire at any one area or zonelisted in Ch 2, Sec 1, [3.25].

7.17 Cables in the vicinity of radio equipment

7.17.1 All cables between antennas and transmitters are tobe routed separately of any other cable.

7.17.2 Where it is necessary to use single-core cables, thearrangement of conductors is to be such as to avoid com-plete or partial loops.

7.18 Cables for submerged bilge pumps

7.18.1 See Ch 2, Sec 3, [9.7].

7.19 Cable trays/protective casings made of plastics materials

7.19.1 Cable trays or protective casings made of plasticsmaterials (thermoplastic or thermosetting plastic material)are to be type tested.

7.19.2 Cable trays/protective casings are to be supple-mented by metallic fixing and straps such that in the eventof a fire they, and the cables affixed, are prevented from fall-ing and causing injury to personnel and/or an obstruction toany escape route.When used on open deck, they are to be protected againstU.V. light.

7.19.3 The load on the cable trays/ protective casings is tobe within the Safe Working Load (SWL). The support spac-ing is not to be greater than the manufacturer recommenda-tions nor in excess of spacing at SWL test. In general, thespacing is not to exceed 2 meters.

7.19.4 The selection and spacing of cable tray/protectivecasing supports are to take into account:• cable trays/protective casings’ dimensions• mechanical and physical properties of their material• mass of cable trays/protective casings• loads due weight of cables, external forces, thrust forces

and vibrations• maximum accelerations to which the system may be

subjected• combination of loads.

7.19.5 The sum of the cables total cross-sectional area,based on the cables external diameter is not to exceed 40%of the protective casing internal cross-sectional area. Thisdoes not apply to a single cable in a protective casing.

8 Various appliances

8.1 Lighting fittings

8.1.1 Lighting fittings are to be so arranged as to preventtemperature rises which could damage the cables and wir-ing.Note 1: Where the temperature of terminals of lighting fittingsexceeds the maximum conductor temperature permitted for the


Pt C, Ch 2, Sec 12

supplied cable (see Ch 2, Sec 3, [9.9]), special installation arrange-ments, such as terminal boxes thermally insulated from the lightsource, are to be provided.

8.1.2 Lighting fittings are to be so arranged as to preventsurrounding material from becoming excessively hot.

8.1.3 Lighting fittings are to be secured in place such thatthey cannot be displaced by the motion of the vessel.

8.1.4 Emergency lights are to be marked for easy identifica-tion.

8.2 Heating appliances

8.2.1 Space heaters are to be so installed that clothing,bedding and other flammable material cannot come in con-tact with them in such a manner as to cause risk of fire.Note 1: To this end, for example, hooks or other devices for hang-ing garments are not to be fitted above space heaters or, whereappropriate, a perforated plate of incombustible material is to bemounted above each heater, slanted to prevent hanging anythingon the heater itself.

8.2.2 Space heaters are to be so installed that there is norisk of excessive heating of the bulkheads or decks onwhich or next to which they are mounted.

8.2.3 Combustible materials in the vicinity of space heatersare to be protected by suitable incombustible and thermal-insulating materials.

8.3 Heating cables and tapes or other heating elements

8.3.1 Heating cables and tapes or other heating elementsare not to be installed in contact with combustible materials.Where they are installed close to such materials, they are tobe separated by means of a non-flammable material.


Pt C, Ch 2, Sec 13

SECTION 13 HIGH VOLTAGE INSTALLATIONS

1 General

1.1 Field of application

1.1.1 The following requirements apply to a.c. three-phasesystems with nominal voltage exceeding 1kV, the nominalvoltage being the voltage between phases.

If not otherwise stated herein, construction and installationapplicable to low voltage equipment stated in Part C, Chap-ter 2 generally apply to high voltage equipment.

1.2 Nominal system voltage

1.2.1 The nominal system voltage is not to exceed 15 kV.Note 1: Where necessary for special application, higher voltagesmay be accepted by the Society.

1.3 High-voltage, low-voltage segregation

1.3.1 Equipment with voltage above about 1 kV is not to beinstalled in the same enclosure as low voltage equipment,unless segregation or other suitable measures are taken toensure that access to low voltage equipment is obtainedwithout danger.

2 System design

2.1 Distribution

2.1.1 It is to be possible to split the main switchboard intoat least two independent sections, by means of at least onecircuit breaker or other suitable disconnecting devices,each supplied by at least one generator. If two separateswitchboards are provided and interconnected with cables,a circuit breaker is to be provided at each end of the cable.Services which are duplicated are to be divided betweenthe sections.

2.1.2 In the event of an earth fault, the current is not to begreater than full load current of the largest generator on theswitch-board or relevant switchboard section and not lessthan three times the minimum current required to operateany device against earth fault.

It is to be assured that at least one source neutral to groundconnection is available whenever the system is in the ener-gised mode. Electrical equipment in directly earthed neutralor other neutral earthed systems is to withstand the currentdue to a single phase fault against earth for the time neces-sary to trip the protection device.

2.1.3 Means of disconnection are to be fitted in the neutralearthing connection of each generator so that the generatormay be disconnected for maintenance and for insulationresistance measurement.

2.1.4 All earthing impedances are to be connected to thehull. The connection to the hull is to be so arranged that anycirculating currents in the earth connections do not interferewith radio, radar, communication and control equipmentcircuits.

2.1.5 In systems with neutral earthed, connection of theneutral to the hull is to be provided for each section.

2.1.6 Alternators running in parallel may have a commonneutral connection to earth provided they are suitablydesigned to avoid excessive circulating currents.

This is particularly important if the alternators are of differ-ent size and make. Alternators in which the third harmoniccontent does not exceed 5% may be considered adequate.

Note 1: This would mostly occur with a neutral bus with a singlegrounding resistor with the associated neutral switching. Whereindividual resistors are used, circulation of the third harmonic cur-rents between paralleled alternators is minimised.

2.1.7 In systems with earthed neutral, resistors or other cur-rent-limiting devices for the connection of the neutrals tothe hull are to be provided for each section in which thesystems are split [2.1.2].

2.2 Degrees of protection

2.2.1 Each part of the electrical installation is to be pro-vided with a degree of protection appropriate to the loca-tion, as a minimum the requirements of IEC Publication60092-201.

2.2.2 The degree of protection of enclosures of rotatingelectrical machines is to be at least IP 23.

The degree of protection of terminals is to be at least IP 44.

For motors installed in spaces accessible to unqualified per-sonnel, a degree of protection against approaching or con-tact with live or moving parts of at least IP 4X is required.

2.2.3 The degree of protection of enclosures of transform-ers is to be at least IP 23.

For transformers installed in spaces accessible to unquali-fied personnel, a degree of protection of at least IP 4X isrequired.

For transformers not contained in enclosures, see [7.1].

2.2.4 The degree of protection of metal enclosed switch-gear, controlgear assemblies and static convertors is to be atleast IP 32. For switchgear, control gear assemblies andstatic convertors installed in spaces accessible to unquali-fied personnel, a degree of protection of at least IP 4X isrequired.


Pt C, Ch 2, Sec 13

2.3 Insulation

2.3.1 In general, for non type tested equipment phase-to-phase air clearances and phase-to-earth air clearancesbetween non-insulated parts are to be not less than thosespecified in Tab 1.

Intermediate values may be accepted for nominal voltages,provided that the next higher air clearance is observed.

In the case of smaller distances, an appropriate voltageimpulse test is to be applied.

Table 1 : Minimum clearances

2.3.2 Creepage distances between live parts and betweenlive parts and earthed metal parts for standard componentsare to be in accordance with relevant IEC Publications forthe nominal voltage of the system, the nature of the insula-tion material and the transient overvoltage developed byswitch and fault conditions.

For non-standardised parts within the busbar section of aswitchgear assembly, the minimum creepage distance is tobe at least 25 mm/kV and behind current limiting devices,16 mm/kV.

2.4 Protection

2.4.1 Protective devices are to be provided against phase-to-phase faults in the cables connecting the generators tothe main switchboard and against interwinding faults withinthe generators. The protective devices are to trip the genera-tor circuit breaker and to automatically de-excite the gener-ator.

In distribution systems with a neutral earthed, phase-to-earth faults are also to be treated as above.

2.4.2 Any earth fault in the system is to be indicated bymeans of a visual and audible alarm.

In low impedance or direct earthed systems provision is tobe made to automatically disconnect the faulty circuits. Inhigh impedance earthed systems, where outgoing feederswill not be isolated in case of an earth fault, the insulationof the equipment is to be designed for the phase-to-phasevoltage.

A system is defined effectively earthed (low impedance)when this factor is lower than 0,8. A system is defined non-effectively earthed (high impedance) when this factor ishigher than 0,8.

Note 1: Earthing factor is defined as the ratio between the phase-to-earth voltage of the health phase and the phase-to-phase voltage.This factor may vary between 1/31/2 and 1.

2.4.3 Power transformers are to be provided with overloadand short circuit protection.

When transformers are connected in parallel, tripping of theprotective devices on the primary side is to automaticallytrip the switch connected on the secondary side.

2.4.4 Voltage transformers are to be provided with over-load and short circuit protection on the secondary side.

2.4.5 Fuses are not to be used for overload protection.

2.4.6 Lower voltage systems supplied through transformersfrom high voltage systems are to be protected against over-voltages. This may be achieved by:

a) direct earthing of the lower voltage system

b) appropriate neutral voltage limiters

c) earthed screen between the primary and secondarywindings of transformers.

3 Rotating machinery

3.1 Stator windings of generators

3.1.1 Generator stator windings are to have all phase endsbrought out for the installation of the differential protection.

3.2 Temperature detectors

3.2.1 Rotating machinery is to be provided with tempera-ture detectors in its stator windings to actuate a visual andaudible alarm in a normally attended position whenever thetemperature exceeds the permissible limit.

If embedded temperature detectors are used, means are tobe provided to protect the circuit against overvoltage.

3.3 Tests

3.3.1 In addition to the tests normally required for rotatingmachinery, a high frequency high voltage test in accor-dance with IEC Publication 60034-15 is to be carried out onthe individual coils in order to demonstrate a satisfactorywithstand level of the inter-turn insulation to steep frontedswitching surges.

4 Power transformers

4.1 General

4.1.1 Dry type transformers are to comply with IEC Publi-cation 60076-11.

Liquid cooled transformers are to comply with IEC Publica-tion 60076.

Oil immersed transformers are to be provided with the fol-lowing alarms and protection:

• liquid level (Low) - alarm

• liquid temperature (High) - alarm

• liquid level (Low) - trip or load reduction

• liquid temperature (High) - trip or load reduction

• gas pressure relay (High) - trip.

Rated voltage, in kV Minimum clearance, in mm

3 - 3,3 55

6 - 6,6 90

10 - 11 120


Pt C, Ch 2, Sec 13

5 Cables

5.1 General

5.1.1 Cables are to be constructed in accordance with IECPublication 60092-353 and 60092-354 or other equivalentStandard.

6 Switchgear and controlgear assemblies

6.1 General

6.1.1 Switchgear and controlgear assemblies are to be con-structed in accordance with IEC Publication 62271-200 andthe following additional requirements.

6.2 Construction

6.2.1 Switchgear is to be of metal-enclosed type in accor-dance with IEC Publication 62271-200 or of the insulation-enclosed type in accordance with IEC Publication 62271-201.

6.2.2 Withdrawable circuit breakers and switches are to beprovided with mechanical locking facilities in both serviceand disconnected positions. For maintenance purposes, keylocking of withdrawable circuit breakers and switches andfixed disconnectors is to be possible.Withdrawable circuit breakers are to be located in the ser-vice position so that there is no relative motion betweenfixed and moving portions.

6.2.3 The fixed contacts of withdrawable circuit breakersand switches are to be so arranged that in the withdrawableposition the live contacts are automatically covered.

6.2.4 For maintenance purposes an adequate number ofearthing and short-circuiting devices is to be provided toenable circuits to be worked on in safety.

6.3 Auxiliary systems

6.3.1 If electrical energy and/or physical energy is requiredfor the operation of circuit-breakers and switches, a storesupply of such energy is to be provided for at least twooperations of all the components.However, the tripping due to overload or short-circuit, andunder-voltage is to be independent of any stored electricalenergy sources. This does not preclude shunt tripping pro-vided that alarms are activated upon lack of continuity inthe release circuits and power supply failures.

6.3.2 When external source of supply is necessary for aux-iliary circuits, at least two external sources of supply are tobe provided and so arranged that a failure or loss of onesource will not cause the loss of more than one generatorset and/or a main switchboard section as described in[2.1.1] and/or set of essential services.Where necessary one source of supply is to be from theemergency source of electrical power for the start up fromdead ship condition.

6.4 High voltage test

6.4.1 A power-frequency voltage test is to be carried out onany switchgear and controlgear assemblies. The test proce-dure and voltages are to be according to IEC Publication62271-200.

7 Installation

7.1 Electrical equipment

7.1.1 Where equipment is not contained in an enclosurebut a room forms the enclosure of the equipment, theaccess doors are to be so interlocked that they cannot beopened until the supply is isolated and the equipmentearthed down.

At the entrance to spaces where high-voltage electricalequipment is installed, a suitable marking is to be placedindicating danger of high voltage. As regards high-voltageelectrical equipment installed outside the aforementionedspaces, similar marking is to be provided.

7.2 Cables

7.2.1 In accommodation spaces, high voltage cables are tobe run in enclosed cable transit systems.

7.2.2 High voltage cables are to be segregated from cablesoperating at different voltage ratings; in particular, they arenot to be run in the same cable bunch, in the same ducts orpipes, or in the same box.

Where high voltage cables of different voltage ratings areinstalled on the same cable tray, the air clearance betweencables is not to be less than the minimum air clearance forthe higher voltage side in [2.3.1]. However, high voltagecables are not to be installed on the same cable tray forcables operating at the nominal system voltage of 1 kV andless.

7.2.3 High voltage cables are generally to be installed oncarrier plating when they are provided with a continuousmetallic sheath or armour which is effectively bonded toearth; otherwise, they are to be installed for their entirelength in metallic castings effectively bonded to earth.

7.2.4 Terminations in all conductors of high voltage cablesare, as far as practicable, to be effectively covered with suit-able insulating material. In terminal boxes, if conductors arenot insulated, phases are to be separated from earth andfrom each other by substantial barriers of suitable insulatingmaterials.

High voltage cables of the radial field type, i.e. having aconductive layer to control the electric field within the insu-lation, are to have terminations which provide electric stresscontrol.

Terminations are to be of a type compatible with the insula-tion and jacket material of the cable and are to be providedwith means to ground all metallic shielding components(i.e. tapes, wires etc.).

7.2.5 High voltage cables are to be readily identifiable bysuitable marking.


Pt C, Ch 2, Sec 13

7.2.6 Before a new high voltage cable installation, or anaddition to an existing installation, is put into service, avoltage withstand test is to be satisfactorily carried out oneach completed cable and its accessories.The test is to be carried out after an insulation resistancetest.

When a d.c. voltage withstand test is carried out, the volt-age is to be not less than:• 1,6 (2,5 Uo + 2 kV) for cables of rated voltage (Uo) up

to and including 3,6 kV, or• 4,2 Uo for higher rated voltages

where Uo is the rated power frequency voltage betweenconductor and earth or metallic screen, for which the cableis designed.

The test voltage is to be maintained for a minimum of15 minutes.

After completion of the test, the conductors are to be con-nected to earth for a sufficient period in order to removeany trapped electric charge.

An insulation resistance test is then repeated.

Alternatively, an a.c. voltage withstand test may be carriedout on the advice of the high voltage cable manufacturer ata voltage not less than the normal operating voltage of thecable, to be maintained for a minimum of 24 hours.

Note 1: Tests specified in IEC Publication 60502 will be consideredadequate.


Pt C, Ch 2, Sec 14

SECTION 14 ELECTRIC PROPULSION PLANT

1 General


1.1.1 The following requirements apply to ships for whichthe main propulsion plants are provided by at least oneelectric propulsion motor and its electrical supply. All elec-trical components of the propulsion plants are to complywith these requirements.

1.1.2 Prime movers are to comply with the requirements ofCh 1, Sec 2.

1.1.3 For the torsional vibration characteristics of the elec-tric propulsion plant, the provisions of Ch 1, Sec 9 apply.

1.1.4 Cooling and lubricating oil systems are to complywith the requirements of Ch 1, Sec 10.

1.1.5 Monitoring and control systems are to comply withthe requirements of Part C, Chapter 3.

1.1.6 Installations assigned an additional notation for auto-mation are to comply with the requirements of Part E, Chap-ter 3 and Part E, Chapter 4.

1.2 Operating conditions

1.2.1 The normal torque available on the electric propul-sion motors for manoeuvring is to be such as to enable thevessel to be stopped or reversed when sailing at its maxi-mum service speed.

1.2.2 Adequate torque margin is to be provided for three-phase synchronous motors to avoid the motor pulling out ofsynchronism during rough weather and when turning.

1.2.3 Means are to be provided to limit the continuousinput to the electric propulsion motor. This value is not toexceed the continuous full load torque for which motor andshafts are designed.

1.2.4 The plant as a whole is to have sufficient overloadcapacity to provide the torque, power and reactive powerneeded during starting and manoeuvring conditions.

Locked rotor torque which may be required in relation tothe operation of the vessel (e.g. for navigation in ice) is to beconsidered.

1.2.5 The electric motors and shaftline are to be con-structed and installed so that, at any speed reached in ser-vice, all the moving components are suitably balanced.

2 Design of the propulsion plant

2.1 General

2.1.1 The electrical power for the propulsion system maybe supplied from generating sets, dedicated to the propul-sion system, or from a central power generation plant,which supplies the ship’s services and electric propulsion.

The minimum configuration of an electric propulsion plantconsists of one prime mover, one generator and one electricmotor. When the electrical production used for propulsionis independent of the shipboard production, the dieselengines driving the electric generators are to be consideredas main engines.

Note 1: When the electric power plant is constituted with 2 genera-tors, the corresponding prime movers are to be considered as mainpropulsion medium. For electrical propulsion plant fitted with morethan 2 generators, they will be considered as auxiliary generators.The corresponding control and monitoring will be consideredaccordingly.

2.1.2 For plants having only one propulsion motor con-trolled via a static convertor, a standby convertor which it iseasy to switch over to is to be provided. Double statorwindings with one convertor for each winding are consid-ered as an alternative solution.

2.1.3 In electric propulsion plants having two or more con-stant voltage propulsion generating sets, the electricalpower for the ship’s auxiliary services may be derived fromthis source. Additional ship’s generators for auxiliary ser-vices need not be fitted provided that effective propulsionand the services mentioned in Ch 2, Sec 3, [2.2.3] aremaintained with any one generating set out of service.

Where transformers are used to supply the ship’s auxiliaryservices, see Ch 2, Sec 5.

2.1.4 Plants having two or more propulsion generators, twoor more static convertors or two or more motors on one pro-peller shaft are to be so arranged that any unit may be takenout of service and disconnected electrically, without affect-ing the operation of the others.

2.2 Power supply

2.2.1 Where the plant is intended exclusively for electricpropulsion, voltage variations and maximum voltage are tobe maintained within the limits required in Ch 2, Sec 3.

2.2.2 In special conditions (e.g. during crash-stop manoeu-vres), frequency variations may exceed the limits stipulatedin Ch 2, Sec 3 provided that other equipment operating onthe same network is not unduly affected.


Pt C, Ch 2, Sec 14

2.2.3 The electric plant is to be so designed as to preventthe harmful effects of electromagnetic interference gener-ated by semiconductor convertors, in accordance with Ch 2,Sec 3.

2.3 Auxiliary machinery

2.3.1 Propeller/thruster auxiliary plants are to be supplieddirectly from the main switchboard or from the main distri-bution board or from a distribution board reserved for suchcircuits, at the auxiliary rated voltage.

2.3.2 When the installation has one or more lubricationsystems, devices are to be provided to ensure the monitor-ing of the lubricating oil return temperature.

2.3.3 Propelling machinery installations with a forcedlubrication system are to be provided with alarm deviceswhich will operate in the event of oil pressure loss.

2.4 Electrical Protection

2.4.1 Automatic disconnections of electric propulsionplants which adversely affect the manoeuvrability of theship are to be restricted to faults liable to cause severe dam-age to the equipment.

2.4.2 The following protection of convertors is to be pro-vided:• protection against overvoltage in the supply systems to

which convertors are connected• protection against overcurrents in semiconductor ele-

ments during normal operation• short-circuit protection.

2.4.3 Overcurrent protective devices in the main circuitsare to be set sufficiently high so that there is no possibility ofactivation due to the overcurrents caused in the course ofnormal operation, e.g. during manoeuvring or in heavyseas.

2.4.4 Overcurrent protection may be replaced by auto-matic control systems ensuring that overcurrents do notreach values which may endanger the plant, e.g. by selec-tive tripping or rapid reduction of the magnetic fluxes of thegenerators and motors.

2.4.5 In the case of propulsion plants supplied by genera-tors in parallel, suitable controls are to ensure that, if one ormore generators are disconnected, those remaining are notoverloaded by the propulsion motors.

2.4.6 In three-phase systems, phase-balance protectivedevices are to be provided for the motor circuit which de-excite the generators and motors or disconnect the circuitconcerned.

2.5 Excitation of electric propulsion motor

2.5.1 Each propulsion motor is to have its own exciter.

2.5.2 For plants where only one generator or only onemotor is foreseen, each machine is to be provided with astandby exciter, which it is easy to switch over to.

2.5.3 In the case of multi-propeller propulsion ships, onlyone standby exciter is to be provided. Switch-over opera-tion is to be easy.

2.5.4 For the protection of field windings and cables,means are to be provided for limiting the induced voltagewhen the field circuits are opened. Alternatively, theinduced voltage when the field circuits are opened is to bemaintained at the nominal design voltage.

2.5.5 In excitation circuits, there is to be no overload pro-tection causing the opening of the circuit, except for excita-tion circuits with semiconductor convertors.

2.5.6 Each exciter is to be supplied by a separate feeder.

3 Construction of rotating machines and semiconductor convertors

3.1 Ventilation

3.1.1 Where electrical machines are fitted with an inte-grated fan and are to be operated at speeds below the ratedspeed with full load torque, full load current, full load exci-tation or the like, the design temperature rise is not to beexceeded.

3.1.2 Where electrical machines or convertors are force-ventilated, at least two fans, or other suitable arrangements,are to be provided so that limited operation is possible inthe event of one fan failing.

3.2 Protection against moisture and con-densate

3.2.1 Machines and equipment which may be subject tothe accumulation of moisture and condensate are to be pro-vided with effective means of heating. The latter is to beprovided for motors above 500 kW, in order to maintain thetemperature inside the machine at about 3°C above theambient temperature.

3.2.2 Provision is to be made to prevent the accumulationof bilge water, which is likely to enter inside the machine.

3.3 Rotating machines

3.3.1 Electrical machines are to be able to withstand theexcess speed which may occur during operation of the ship.

3.3.2 The design of rotating machines supplied by staticconvertors is to consider the effects of harmonics.

3.3.3 The winding insulation of electrical machines is to becapable of withstanding the overvoltage which may occurin manoeuvring conditions.

3.3.4 The design of a.c. machines is to be such that theycan withstand without damage a sudden short-circuit attheir terminals under rated operating conditions.


Pt C, Ch 2, Sec 14

3.3.5 The obtainable current and voltage of exciters andtheir supply are to be suitable for the output required duringmanoeuvring and overcurrent conditions, including short-circuit in the transient period.

3.4 Semiconductor convertors

3.4.1 The following limiting repetitive peak voltages URM

are to be used as a base for each semiconductor valve:

• when connected to a supply specifically for propellerdrives:

URM = 1,5 UP

• when connected to a common main supply:

URM = 1,8 UP

where

UP : Peak value of the rated voltage at the input ofthe semiconductor convertor.

3.4.2 For semiconductor convertor elements connected inseries, the values in [3.4.1] are to be increased by 10%.Equal voltage distribution is to be ensured.

3.4.3 For parallel-connected convertor elements, an equalcurrent distribution is to be ensured.

3.4.4 Means are to be provided, where necessary, to limitthe effects of the rate of harmonics to the system and toother semiconductor convertors. Suitable filters are to beinstalled to keep the current and voltage within the limitsgiven in Ch 2, Sec 2.

4 Control and monitoring

4.1 General

4.1.1 The control and monitoring systems, including com-puter based systems, are to be type approved, according toCh 3, Sec 6.

4.2 Power plant control systems

4.2.1 The power plant control systems are to ensure thatadequate propulsion power is available, by means of auto-matic control systems and/or manual remote control sys-tems.

4.2.2 The automatic control systems are to be such that, inthe event of a fault, the propeller speed and direction ofthrust do not undergo substantial variations.

4.2.3 Failure of the power plant control system is not tocause complete loss of generated power (i.e. blackout) orloss of propulsion.

4.2.4 The loss of power plant control systems is not tocause variations in the available power; i.e. starting or stop-ping of generating sets is not to occur as a result.

4.2.5 Where power-aided control (for example with electri-cal, pneumatic or hydraulic aid) is used for manual opera-tion, failure of such aid is not to result in interruption ofpower to the propeller. Any such device is to be capable ofpurely manual local operation.

4.2.6 The control system is to include the following mainfunctions:

• monitoring of the alarms: any event critical for theproper operation of an essential auxiliary or a main ele-ment of the installation requiring immediate action toavoid a breakdown is to activate an alarm

• speed or pitch control of the propeller

• shutdown or slow down when necessary.

4.2.7 Where the electric propulsion system is supplied bythe main switchboard together with the ship’s services, loadshedding of the non-essential services and /or power limita-tion of the electric propulsion is to be provided. An alarm isto be triggered in the event of power limitation or loadshedding.

4.2.8 The risk of blackout due to electric propulsion opera-tion is to be eliminated. At the request of the Society, a fail-ure mode and effects analysis is to be carried out todemonstrate the reliability of the system.

4.3 Indicating instruments

4.3.1 In addition to the provisions of Part C, Chapter 3 ofthe Rules, instruments indicating consumed power andpower available for propulsion are to be provided at eachpropulsion remote control position.

4.3.2 The instruments specified in [4.3.3] and [4.3.4] inrelation to the type of plant are to be provided on the powercontrol board or in another appropriate position.

4.3.3 The following instruments are required for each pro-pulsion alternator:

• an ammeter on each phase, or with a selector switch toall phases

• a voltmeter with a selector switch to all phases

• a wattmeter

• a tachometer or frequency meter

• a power factor meter or a var-meter or a field ammeterfor each alternator operating in parallel

• a temperature indicator for direct reading of the temper-ature of the stator windings, for each alternator ratedabove 500 kW.

4.3.4 The following instruments are required for each a.c.propulsion motor:

• an ammeter on the main circuit

• an embedded sensor for direct reading of the tempera-ture of the stator windings, for motors rated above500 kW


Pt C, Ch 2, Sec 14

• an ammeter on the excitation circuit for each synchro-nous motor

• a voltmeter for the measurement of the voltage betweenphases of each motor supplied through a semiconductorfrequency convertor.

4.3.5 Where a speed measuring system is used for controland indication, the system is to be duplicated with separatesensor circuits and separate power supply.

4.3.6 An ammeter is to be provided on the supply circuitfor each propulsion semiconductor bridge.

4.4 Alarm system

4.4.1 An alarm system is to be provided, in accordancewith the requirements of Part C, Chapter 3. The system is togive an indication at the control positions when the param-eters specified in [4.4] assume abnormal values or anyevent occurs which can affect the electric propulsion.

4.4.2 Where an alarm system is provided for other essentialequipment or installations, the alarms in [4.4.1] may beconnected to such system.

4.4.3 Critical alarms for propulsion are to be indicated tothe bridge separately.

4.4.4 The following alarms are to be provided, whereapplicable:• high temperature of the cooling air of machines and

semiconductor convertors provided with forced ventila-tion (see [4.4.4], Note 1)

• reduced flow of primary and secondary coolants ofmachines and semiconductor convertors having aclosed cooling system with a heat exchanger

• leakage of coolant inside the enclosure of machines andsemiconductor convertors with liquid-air heat exchangers

• high winding temperature of generators and propulsionmotors, where required (see [4.3])

• low lubricating oil pressure of bearings for machineswith forced oil lubrication

• tripping of protective devices against overvoltages insemiconductor convertors (critical alarm)

• tripping of protection on filter circuits to limit the distur-bances due to semiconductor convertors

• tripping of protective devices against overcurrents up toand including short-circuit in semiconductor convertors(critical alarm)

• voltage unbalance of three-phase a.c. systems suppliedby semiconductor frequency convertors

• earth fault for the main propulsion circuit (see [4.4.4],Note 2)

• earth fault for excitation circuits of propulsion machines(see [4.4.4], Note 3).

Note 1: As an alternative to the air temperature of convertors or tothe airflow, the supply of electrical energy to the ventilator or thetemperature of the semiconductors may be monitored.

Note 2: In the case of star connected a.c. generators and motorswith neutral points earthed, this device may not detect an earthfault in the entire winding of the machine.

Note 3: This may be omitted in brushless excitation systems and inthe excitation circuits of machines rated up to 500 kW. In suchcases, lamps, voltmeters or other means are to be provided todetect the insulation status under operating conditions.

4.5 Reduction of power

4.5.1 Power is to be automatically reduced in the followingcases:

• low lubricating oil pressure of bearings of propulsiongenerators and motors

• high winding temperature of propulsion generators andmotors

• fan failure in machines and convertors provided withforced ventilation, or failure of cooling system

• lack of coolant in machines and semiconductor conver-tors

• load limitation of generators or inadequate availablepower.

4.5.2 When power is reduced automatically, this is to beindicated at the propulsion control position (critical alarm).

4.5.3 Switching-off of the semiconductors in the event ofabnormal service operation is to be provided in accordancewith the manufacturer’s specification.

5 Installation

5.1 Ventilation of spaces

5.1.1 Loss of ventilation to spaces with forced air cooling isnot to cause loss of propulsion. To this end, two sets of ven-tilation fans are to be provided, one acting as a standby unitfor the other. Equivalent arrangements using several inde-pendently supplied fans may be considered.

5.2 Cable runs

5.2.1 Instrumentation and control cables are to complywith the requirements of Ch 3, Sec 5 of the Rules.

5.2.2 Where there is more than one propulsion motor, allcables for any one machine are to be run as far as is practi-cable away from the cables of other machines.

5.2.3 Cables which are connected to the sliprings of syn-chronous motors are to be suitably insulated for the voltageto which they are subjected during manoeuvring.

6 Tests

6.1 Test of rotating machines

6.1.1 The test requirements are to comply with Ch 2, Sec 4.

6.1.2 For rotating machines, such as synchronous genera-tors and synchronous electric motors, of a power of morethan 1 MW, a quality plan detailing the different controlsduring the machine assembly is to be submitted to the Soci-ety for approval.


Pt C, Ch 2, Sec 14

6.1.3 In relation to the evaluation of the temperature rise, itis necessary to consider the supplementary thermal lossesinduced by harmonic currents in the stator winding. To thisend, two methods may be used:

• direct test method, when the electric propulsion motoris being supplied by its own frequency convertor, and/orback to back arrangement according to the supplier’sfacility

• indirect test method as defined in Ch 2, App 1; in thiscase, a validation of the estimation of the temperatureexcess due to harmonics is to be documented. A justifi-cation based on a computer program calculation maybe taken into consideration, provided that validation ofsuch program is demonstrated by previous experience.

6.1.4 Rotating machines used for propulsion or manoeu-vring are to be subjected to the tests stated in Ch 2, Sec 4,[5.1.1].

7 Specific requirements for PODs

7.1 General

7.1.1 The requirements for the structural part of a POD arespecified in Pt B, Ch 10, Sec 1, [11].

7.1.2 When used as steering manoeuvring system, thePOD is to comply with the requirements of Ch 1, Sec 11.

7.2 Rotating commutator

7.2.1 As far as the electrical installation is concerned, theelectric motor is supplied by a rotating commutator whichrotates with the POD. The fixed part of the power transmis-sion is connected to the ship supply, which uses the samecomponents as a conventional propulsion system. Slidingcontacts with a suitable support are used between the fixedand rotating parts.

7.2.2 The rotating commutator is to be type approved. Typetests are to be carried out, unless the manufacturer can pro-duce evidence based on previous experience indicating thesatisfactory performance of such equipment on board ships.

7.2.3 A test program is to be submitted to the Society forapproval. It is to be to demonstrated that the power trans-mission and transmission of low level signals are notaffected by the environmental and operational conditionsprevailing on board. To this end, the following checks andtests are to be considered:

• check of the protection index (IP), in accordance withthe location of the rotating commutator

• check of the clearances and creepage distances

• check of insulation material (according to the test proce-dure described in IEC Publication 60112)

• endurance test:

After the contact pressure and rated current are set, thecommutator is subjected to a rotation test. The numberof rotations is evaluated taking into consideration the

ship operation and speed rotation control system. Thepossibility of turning the POD 180° to proceed asternand 360° to return to the original position is to be con-sidered. The commutator may be submitted to cyclescomprising full or partial rotation in relation to the useof the POD as steering gear. The voltage drops and cur-rent are to be recorded.

An overload test is to be carried out in accordance withCh 2, Sec 4 (minimum 150%, 15 seconds)

• check of the behaviour of the sliprings when subjectedto the vibration defined in Ch 3, Sec 6

• check of the behaviour of the sliprings, after damp heattest, as defined in Part C, Chapter 3, and possible corro-sion of the moving parts and contacts.

After the damp heat test, the following are to be carried out:

• insulation measurement resistance test: the minimumresistance is to be in accordance with Ch 2, Sec 4, Tab 2

• dielectric strength test as defined in Ch 2, Sec 4.

7.3 Electric motor

7.3.1 The thermal losses are dissipated by the liquid cool-ing of the bulb and by the internal ventilation of the POD.The justification for the evaluation of the heating balancebetween the sea water and air cooling is to be submitted tothe Society.

Note 1: The calculation method used for the evaluation of the cool-ing system (mainly based on computer programs) is to be docu-mented. The calculation method is to be justified based on theexperience of the designer of the system. The results of scale modeltests or other methods may be taken into consideration.

7.3.2 Means to adjust the air cooler characteristics are tobe provided on board, in order to obtain an acceptable tem-perature rise of the windings. Such means are to be set fol-lowing the dock and sea trials.

7.3.3 Vibrations of the electric motor are to be monitored.The alarm set point is to be defined in accordance with themanufacturer recommendation.

7.4 Instrumentation and associated devices

7.4.1 Means are to be provided to transmit the low levelsignals connected to the sensors located in the POD.

7.5 Additional tests and tests on board

7.5.1 Tests of electric propulsion motors are to be carriedout in accordance with Ch 2, Sec 4, and other tests inaccordance with Ch 1, Sec 15.

7.5.2 Tests are to be performed to check the validation ofthe temperature rise calculation.

7.5.3 Tests on board are described in Ch 1, Sec 15, [3.9].


Pt C, Ch 2, Sec 15

SECTION 15 TESTING

1 General

1.1 Rule application

1.1.1 Before a new installation, or any alteration or addi-tion to an existing installation, is put into service, the elec-trical equipment is to be tested in accordance with [3], [4]and [5] to the satisfaction of the Surveyor in charge.

1.2 Insulation-testing instruments

1.2.1 Insulation resistance may be measured with an instru-ment applying a voltage of at least 500 V. The measurementwill be taken when the deviation of the measuring device isstabilised.Note 1: Any electronic devices present in the installation are to bedisconnected prior to the test in order to prevent damage.

1.2.2 For high voltage installation, the measurement is tobe taken with an instrument applying a voltage adapted tothe rated value and agreed with the Society.

2 Type approved components

2.1

2.1.1 The following components are to be type approved orin accordance with [2.1.2]:• electrical cables• transformers• rotating machines• electrical convertors for primary essential services• switching devices (circuit-breakers, contactors, discon-

nectors, etc.) and overcurrent protective devices• sensors, alarm panels, electronic protective devices,

automatic and remote control equipment, actuators,safety devices for installations intended for essentialservices (steering, controllable pitch propellers, propul-sion machinery, etc.), electronic speed regulators formain or auxiliary engines

• computers used for tasks essential to safety.

2.1.2 Case by case approval based on submission of ade-quate documentation and execution of tests may also begranted at the discretion of the Society.

3 Insulation resistance

3.1 Lighting and power circuits

3.1.1 The insulation resistance between all insulated poles(or phases) and earth and, where practicable, between poles(or phases), is to be at least 1 MΩ in ordinary conditions.

The installation may be subdivided to any desired extentand appliances may be disconnected if initial tests giveresults less than that indicated above.

3.2 Internal communication circuits

3.2.1 Circuits operating at a voltage of 50 V and above areto have an insulation resistance between conductors andbetween each conductor and earth of at least 1 MΩ.

3.2.2 Circuits operating at voltages below 50 V are to havean insulation resistance between conductors and betweeneach conductor and earth of at least 0,33 MΩ.

3.2.3 If necessary, any or all appliances connected to thecircuit may be disconnected while the test is being con-ducted.

3.3 Switchboards

3.3.1 The insulation resistance between each busbar andearth and between each insulated busbar and the busbarconnected to the other poles (or phases) of each mainswitchboard, emergency switchboard, section board, etc. isto be not less than 1 MΩ.

3.3.2 The test is to be performed before the switchboard isput into service with all circuit-breakers and switches open,all fuse-links for pilot lamps, earth fault-indicating lamps,voltmeters, etc. removed and voltage coils temporarily dis-connected where otherwise damage may result.

3.4 Generators and motors

3.4.1 The insulation resistance of generators and motors, innormal working condition and with all parts in place, is tobe measured and recorded.

3.4.2 The test is to be carried out with the machine hotimmediately after running with normal load.

3.4.3 The insulation resistance of generator and motor con-nection cables, field windings and starters is to be at least1 MΩ.

4 Earth

4.1 Electrical constructions

4.1.1 Tests are to be carried out, by visual inspection or bymeans of a tester, to verify that all earth-continuity conduc-tors and earthing leads are connected to the frames of appa-ratus and to the hull, and that in socket-outlets havingearthing contacts, these are connected to earth.


Pt C, Ch 2, Sec 15

4.2 Metal-sheathed cables, metal pipes or conduits

4.2.1 Tests are to be performed, by visual inspection or bymeans of a tester, to verify that the metal coverings of cablesand associated metal pipes, conduits, trunking and casingsare electrically continuous and effectively earthed.

5 Operational tests

5.1 Generating sets and their protective devices

5.1.1 Generating sets are to be run at full rated load to ver-ify that the following are satisfactory:

• electrical characteristics

• commutation (if any)

• lubrication

• ventilation

• noise and vibration level.

5.1.2 Suitable load variations are to be applied to verify thesatisfactory operation under steady state and transient con-ditions (see Ch 2, Sec 4, [2] ) of:

• voltage regulators

• speed governors.

5.1.3 Generating sets intended to operate in parallel are tobe tested over a range of loading up to full load to verifythat the following are satisfactory:

• parallel operation

• sharing of the active load

• sharing of the reactive load (for a.c. generators).

Synchronising devices are also to be tested.

5.1.4 The satisfactory operation of the following protectivedevices is to be verified:

• overspeed protection

• overcurrent protection (see [5.1.4], Note 1)

• load-shedding devices

• any other safety devices.

For sets intended to operate in parallel, the correct opera-tion of the following is also to be verified:

• reverse-power protection for a.c. installations (orreverse-current protection for d.c. installations)

• minimum voltage protection.

Note 1: Simulated tests may be used to carry out this check whereappropriate.

5.1.5 The satisfactory operation of the emergency source ofpower and of the transitional source of power, whenrequired, is to be tested. In particular, the automatic startingand the automatic connection to the emergency switch-board, in case of failure of the main source of electricalpower, are to be tested.

5.2 Switchgear

5.2.1 All switchgear is to be loaded and, when found nec-essary by the attending Surveyor, the operation of overcur-rent protective devices is to be verified (see [5.2.1], Note 1).

Note 1: The workshop test is generally considered sufficient toensure that such apparatus will perform as required while in opera-tion.

5.2.2 Short-circuit tests may also be required at the discre-tion of the Society in order to verify the selectivity charac-teristics of the installation.

5.3 Consuming devices

5.3.1 Electrical equipment is to be operated under normalservice conditions (though not necessarily at full load orsimultaneously) to verify that it is suitable and satisfactoryfor its purpose.

5.3.2 Motors and their starters are to be tested under nor-mal operating conditions to verify that the following are sat-isfactory:

• power

• operating characteristics

• commutation (if any)

• speed

• direction of rotation

• alignment.

5.3.3 The remote stops foreseen are to be tested.

5.3.4 Lighting fittings, heating appliances etc. are to betested under operating conditions to verify that they are suit-able and satisfactory for their purposes (with particularregard to the operation of emergency lighting).

5.4 Communication systems

5.4.1 Communication systems, order transmitters andmechanical engine-order telegraphs are to be tested to ver-ify their suitability.

5.5 Installations in areas with a risk of explosion

5.5.1 Installations and the relevant safety certification areto be examined to ensure that they are of a type permittedin the various areas and that the integrity of the protectionconcept has not been impaired.

5.6 Voltage drop

5.6.1 Where it is deemed necessary by the attending Sur-veyor, the voltage drop is to be measured to verify that thepermissible limits are not exceeded (see Ch 2, Sec 3,[9.11.4]).


Pt C, Ch 2, App 1

APPENDIX 1 INDIRECT TEST METHOD FOR SYNCHRONOUS MACHINES

1 General

1.1 Test method

1.1.1 The machine is to be subject to the three separaterunning tests specified below (see Fig 1) when it is complete(with covers, heat exchangers, all control devices and sen-sors), the exciter circuit is connected to its normal supply orto a separate supply having the same characteristics, andthe supply is fitted with the necessary measuring instru-ments:

• Test N° 1: No load test at rated voltage and current onrotor, stator winding in open circuit. The temperaturerise of the stator winding depends, in such case, on themagnetic circuit losses and mechanical losses due toventilation, where:

• Δts1 is the stator temperature rise

• Δtr1 is the rotor temperature rise.

• Test N° 2: Rated stator winding current with the termi-nals short-circuited. The temperature of the stator wind-ing depends on the thermal Joule losses and mechanicallosses, as above, where:


• Δtr2 is the rotor temperature rise, which for test N° 2is negligible.

• Test N° 3: Zero excitation. The temperature of all wind-ings depends on the mechanical losses due to frictionand ventilation, where:


• Δtr3 is the rotor temperature rise.

Note 1: The synchronous electric motor is supplied at its ratedspeed by a driving motor. The temperature balance will be consid-ered as being obtained, when the temperature rise does not vary bymore than 2°C per hour.

1.1.2 Temperature measurements of the stator winding canbe based on the use of embedded temperature sensors ormeasurement of winding resistance. When using the resis-tance method for calculation of the temperature rise, theresistance measurement is to be carried out as soon as themachine is shut down.

The rotor temperature rise is obtained by calculation ofrotor resistance, Rrotor = U/Ir , where U and I are the volt-age and current in the magnetic field winding.

The following parameters are recorded, every 1/2 hour:

• temperature sensors as well as the stator current andvoltage

• the main field voltage and current

• the bearing temperatures (embedded sensor or ther-mometer), and the condition of cooling of the bearings,which are to be compared to those expected on board.

Figure 1 : Schematic diagram used for the test

Driving motor

Shaftcoupling

Propulsion electric motor

Rotating diodsExciter rotating machine

Exc

iter

circ

uit

TEST N˚1 Open circuit and TEST N˚3

TEST N˚2 Short circuit


Pt C, Ch 2, App 1

1.1.3 The tests described above allow the determination ofthe final temperature rise of stator and rotor windings withan acceptable degree of accuracy.• The temperature rise of the stator winding is estimated

as follows:Δt stator = Δts1 + Δts2 − Δts3Δt stator winding is to be corrected by the supplemen-tary temperature rise due to current harmonics evalu-ated by the manufacturer

• Considering that in test N° 1 the magnetic field windingcurrent Irt is different from the manufacturer’s estimatedvalue Ir (due to the fact that the cos ϕ in operation is not

equal to 1), the temperature rise of the rotor is to be cor-rected as follows:

Δt rotor = (Δtr1 − Δtr3) x (rated loading conditions Ir/ testloading conditions Irt)2 + Δtr3

1.1.4 In the indirect method, a possible mutual influence ofthe temperature rise between the stator and the rotor is nottaken into consideration. The test results may be representa-tive of the temperature rise on board ship, but a margin of10 to 15°C is advisable compared with the permitted tem-perature of the Rules and the measure obtained during tests.


Pt C, Ch 2, App 1



Fire Protection

Chapter 3

AUTOMATION

SECTION 1 GENERAL REQUIREMENTS

SECTION 2 DESIGN REQUIREMENTS

SECTION 3 COMPUTER BASED SYSTEMS

SECTION 4 CONSTRUCTIONAL REQUIREMENTS

SECTION 5 INSTALLATION REQUIREMENTS

SECTION 6 TESTING

APPENDIX 1 TYPE TESTING PROCEDURE FOR CRANKCASE OIL MIST DETECTION AND ALARM EQUIPMENT



Pt C, Ch 3, Sec 1

SECTION 1 GENERAL REQUIREMENTS

1 General

1.1 Field of application

1.1.1 The following requirements apply to automation sys-tems, installed on all ships, intended for essential servicesas defined in Ch 2, Sec 1. They also apply to systemsrequired in Part C, Chapter 1 and Part C, Chapter 2,installed on all ships.

1.1.2 This chapter is intended to avoid that failures or mal-functions of automation systems associated with essentialand non-essential services cause danger to other essentialservices.

1.1.3 Requirements for unattended machinery spaces andfor additional notations are specified in Part E.

1.2 Regulations and standards

1.2.1 The regulations and standards applicable are thosedefined in Ch 2, Sec 1.

1.3 Definitions

1.3.1 Unless otherwise stated, the terms used in this chap-ter have the definitions laid down in Ch 2, Sec 1 or in theIEC standards. The following definitions also apply:• Alarm indicator is an indicator which gives a visible

and/or audible warning upon the appearance of one ormore faults to advise the operator that his attention isrequired.

• Alarm system is a system intended to give a signal in theevent of abnormal running condition.

• Application software is a software performing tasks spe-cific to the actual configuration of the computer basedsystem and supported by the basic software.

• Automatic control is the control of an operation withoutdirect or indirect human intervention, in response to theoccurrence of predetermined conditions.

• Automation systems are systems including control sys-tems and monitoring systems.

• Basic software is the minimum software, which includesfirmware and middleware, required to support theapplication software.

• Cold standby system is a duplicated system with a man-ual commutation or manual replacement of cards whichare live and non-operational. The duplicated system isto be able to achieve the operation of the main systemwith identical performance, and be operational within10 minutes.

• Computer based system is a system of one or more com-puters, associated software, peripherals and interfaces,and the computer network with its protocol.

• Control station is a group of control and monitoringdevices by means of which an operator can control andverify the performance of equipment.

• Control system is a system by which an intentionalaction is exerted on an apparatus to attain given pur-poses.

• Expert system is an intelligent knowledge-based systemthat is designed to solve a problem with information thathas been compiled using some form of human exper-tise.

• Fail safe is a design property of an item in which thespecified failure mode is predominantly in a safe direc-tion with regard to the safety of the ship, as a primaryconcern.

• Full redundant is used to describe an automation systemcomprising two (identical or non-identical) independentsystems which perform the same function and operatesimultaneously.

• Hot standby system is used to describe an automationsystem comprising two (identical or non-identical) inde-pendent systems which perform the same function, oneof which is in operation while the other is on standbywith an automatic change-over switch.

• Instrumentation is a sensor or monitoring element.

• Integrated system is a system consisting of two or moresubsystems having independent functions connected bya data transmission network and operated from one ormore workstations.

• Local control is control of an operation at a point on oradjacent to the controlled switching device.

• Monitoring system is a system designed to observe thecorrect operation of the equipment by detecting incor-rect functioning (measure of variables comparedwith specified value).

• Safety system is a system intended to limit the conse-quence of failure and is activated automatically whenan abnormal condition appears.

• Software is the program, procedures and associateddocumentation pertaining to the operation of the com-puter system.

• Redundancy is the existence of more than one meansfor performing a required function.

• Remote control is the control from a distance of appara-tus by means of an electrical or other link.

1.4 General

1.4.1 The automation systems and components, as indi-cated in Ch 2, Sec 15, [2], are to be chosen from among thelist of type approved products.


Pt C, Ch 3, Sec 1

They are to be approved on the basis of the applicablerequirements of these Rules and in particular those stated inthis Chapter.

Case by case approval may also be granted at the discretionof the Society, based on submission of adequate documen-tation and subject to the satisfactory outcome of anyrequired tests.

1.4.2 Main and auxiliary machinery essential for the pro-pulsion, control and safety of the ship shall be providedwith effective means for its operation and control.

1.4.3 Control, alarm and safety systems are to be based onthe fail-to-safety principle.

1.4.4 Failure of automation systems is to generate an alarm.

1.4.5 Detailed indication, alarm and safety requirementsregarding automation systems for individual machinery andinstallations are to be found in tables located in Part C,Chapter 1 and in Part E, Chapter 3.

Each row of these tables is to correspond to one indepen-dant sensor.

2 Documentation

2.1 General

2.1.1 Before the actual construction is commenced, theManufacturer, Designer or Shipbuilder is to submit to the

Society the documents (plans, diagrams, specifications andcalculations) requested in this Section.

The list of documents requested is to be intended as guid-ance for the complete set of information to be submitted,rather than an actual list of titles.

The Society reserves the right to request the submission ofadditional documents in the case of non-conventionaldesign or if it is deemed necessary for the evaluation of thesystem, equipment or components.

Plans are to include all the data necessary for their interpre-tation, verification and approval.

Unless otherwise agreed with the Society, documents forapproval are to be sent in triplicate if submitted by the Ship-yard and in four copies if submitted by the equipment sup-plier. Documents requested for information are to be sent induplicate.

In any case, the Society reserves the rights to require addi-tional copies, when deemed necessary.

2.2 Documents to be submitted

2.2.1 The documents listed in Tab 1 are to be submitted.

2.3 Documents for computer based system

2.3.1 General

For computer based systems, the documents listed in Tab 2are to be submitted.

Table 1 : Documentation to be submitted

Table 2 : Computer based system documentation

N° I/A (1) Documentation

1 I The general specification for the automation of the ship

2 A The detailed specification of the essential service systems

3 A The list of components used in the automation circuits, and references (Manufacturer, type, etc.)

4 I Instruction manuals

5 I Test procedures for control, alarm and safety systems

6 A A general diagram showing the monitoring and/or control positions for the various installations, with an indication of the means of access and the means of communication between the positions as well as with the engineers

7 A The diagrams of the supply circuits of automation systems, identifying the power source

8 A The list of monitored parameters for alarm/monitoring and safety systems

9 A Diagram of the engineers’ alarm system

(1) A = to be submitted for approval; I = to be submitted for information.

N° I/A (1) Documentation

1 I System description, computer software [2.3.2]

2 A System description, computer hardware [2.3.3]

3 I System reliability analysis [2.3.4]

4 I User interface description [2.3.5]

5 I Test programs [2.3.6]

(1) A = To be submitted for approval I = To be submitted for information.


Pt C, Ch 3, Sec 1

2.3.2 System description, computer softwareThis documentation is to contain:

• a list of all main software modules installed per hard-ware unit with names and version numbers

• a description of all main software which is to include atleast:

- a description of basic software installed per hard-ware unit, including communication software, whenapplicable

- a description of application software.

2.3.3 Description of computer hardwareThe documentation to be submitted is to include:

• hardware information of importance for the applicationand a list of documents that apply to the system

• the supply circuit diagram

• a description of hardware and software tools for equip-ment configuration

• the information to activate the system

• general information for trouble shooting and repairwhen the system is in operation.

2.3.4 System reliability analysisThe documentation to be submitted is to demonstrate thereliability of the system by means of appropriate analysissuch as:

• a failure mode analysis describing the effects due to fail-ures leading to the destruction of the automation sys-tem. In addition, this documentation is to show theconsequences on other systems, if any. This analysis isappraised in accordance with the IEC Publication60812, or a recognised standard

• test report/life test

• MTBF calculation

• any other documentation demonstrating the reliabilityof the system.

2.3.5 User interface descriptionThe documentation is to contain:

• a description of the functions allocated to each operatorinterface (keyboard/screen or equivalent)

• a description of individual screen views (schematics,colour photos, etc.)

• a description of how menus are operated (tree presenta-tion)

• an operator manual providing necessary information forinstallation and use.

2.3.6 Test programsThe following test programs are to be submitted:

• software module/unit test

• software integration test

• system validation test

• on-board test.

Each test program is to include:

• a description of each test item

• a description of the acceptance criteria for each test.

2.4 Documents for type approval of equip-ment

2.4.1 Documents to be submitted for type approval ofequipment are listed hereafter:

• a request for type approval from the manufacturer or hisauthorized representative

• the technical specification and drawings depicting thesystem, its components, characteristics, working princi-ple, installation and conditions of use and, when thereis a computer based system, the documents listed in Tab2

• any test reports previously prepared by specialised labo-ratories.

2.4.2 Documentation to be submitted for type approval ofsoftware is listed in Information Note “Software Assessmentfor Shipboard Computer Based System” (NI-425).

3 Environmental and supply conditions

3.1 General

3.1.1 General

The automation system is to operate correctly when thepower supply is within the range specified in Ch 3, Sec 2.

3.1.2 Environmental conditions

The automation system is to be designed to operate satisfac-torily in the environment in which it is located. The envi-ronmental conditions are described in Ch 2, Sec 2.

3.1.3 Failure behavior

The automation system is to have non-critical behaviour inthe event of power supply failure, faults or restoration ofoperating condition following a fault. If a redundant powersupply is used, it must be taken from an independentsource.

3.2 Power supply conditions

3.2.1 Electrical power supply

The conditions of power supply to be considered aredefined in Ch 2, Sec 2.

3.2.2 Pneumatic power supply

For pneumatic equipment, the operational characteristicsare to be maintained under permanent supply pressure vari-ations of ± 20% of the rated pressure.

Detailed requirements are given in Ch 1, Sec 10.

3.2.3 Hydraulic power supply

For hydraulic equipment, the operational characteristics areto be maintained under permanent supply pressure varia-tions of ± 20% of the rated pressure.

Detailed requirements are given in Ch 1, Sec 10.


Pt C, Ch 3, Sec 1

4 Materials and construction

4.1 General

4.1.1 The choice of materials and components is to bemade according to the environmental and operating condi-tions in order to maintain the proper function of the equip-ment.

4.1.2 The design and construction of the automation equip-ment is to take into account the environmental and operat-ing conditions in order to maintain the proper function ofthe equipment.

4.2 Type approved components

4.2.1 See Ch 2, Sec 15.

5 Alterations and additions

5.1

5.1.1 When an alteration or addition to an approved sys-tem is proposed, plans are to be submitted and approved bythe Society before the work of alteration or addition is com-menced.

5.1.2 A test program for verification and validation of cor-rect operation is to be made available.

5.1.3 Where the modifications may affect compliance withthe rules, they are to be carried out under survey and theinstallation and testing are to be to the Surveyor’s satisfac-tion.


Pt C, Ch 3, Sec 2

SECTION 2 DESIGN REQUIREMENTS

1 General

1.1

1.1.1 All control systems essential for the propulsion, con-trol and safety of the ship shall be independent or designedsuch that failure of one system does not degrade the perfor-mance of another system.

1.1.2 Controlled systems are to have manual operation.

Failure of any part of such systems shall not prevent the useof the manual override.

1.1.3 Automation systems are to have constant perfor-mance.

1.1.4 Safety functions are to be independent of control andmonitoring functions. As far as practicable, control andmonitoring functions are also to be independent.

1.1.5 Control, monitoring and safety systems are to haveself-check facilities. In the event of failure, an alarm is to beactivated.

In particular, failure of the power supply of the automationsystem is to generate an alarm.

1.1.6 When a computer based system is used for control,alarm or safety systems, it is to comply with the require-ments of Ch 3, Sec 3.

1.1.7 The automatic change-over switch is to operate inde-pendently of both systems. When change-over occurs, nostop of the installation is necessary and the latter is not toenter undefined or critical states.

1.1.8 Emergency stops are to be hardwired and indepen-dent of any computer based system.Note 1: Computerized systems may be admitted if evidence isgiven demonstrating they provide a safety level equivalent to ahardwired system.

2 Power supply of automation systems

2.1

2.1.1 Automation systems are to be arranged with an auto-matic change-over to a continuously available stand-bypower supply in case of loss of normal power source.

2.1.2 The capacity of the stand-by power supply is to besufficient to allow the normal operation of the automationsystems for at least half an hour.

2.1.3 Failure of any power supply to an automation systemis to generate an audible and visual alarm.

2.1.4 Power supplies are to be protected against short cir-cuit and overload for each independent automation system.

Power supplies are to be isolated.

3 Control systems

3.1 General

3.1.1 In the case of failure, the control systems used foressential services are to remain in the last position they hadbefore the failure, unless otherwise specified by these Rules.

3.2 Local control

3.2.1 Each system is to be able to be operated manuallyfrom a position located so as to enable visual control ofoperation. For detailed instrumentation for each system,refer to Part C, Chapter 1and Part C, Chapter 2.

It shall also be possible to control the auxiliary machinery,essential for the propulsion and safety of the ship, at or nearthe machinery concerned.

3.3 Remote control systems

3.3.1 When several control stations are provided, controlof machinery is to be possible at one station at a time.

3.3.2 At each location there shall be an indicator showingwhich location is in control of the propulsion machinery.

3.3.3 Remote control is to be provided with the necessaryinstrumentation, in each control station, to allow effectivecontrol (correct function of the system, indication of controlstation in operation, alarm display).

3.3.4 When transferring the control location, no significantalteration of the controlled equipment is to occur. Transferof control is to be protected by an audible warning andacknowledged by the receiving control location. The maincontrol location is to be able to take control withoutacknowledgement.

3.4 Automatic control systems

3.4.1 Automatic starting, operational and control systemsshall include provisions for manually overriding the auto-matic controls.

3.4.2 Automatic control is to be stable in the range of thecontroller in normal working conditions.

3.4.3 Automatic control is to have instrumentation to verifythe correct function of the system.


Pt C, Ch 3, Sec 2

4 Control of propulsion machinery

4.1 Remote control

4.1.1 The requirements mentioned in [3] are to be appliedfor propulsion machinery.

4.1.2 The design of the remote control system shall be suchthat in case of its failure an alarm will be given.

4.1.3 Supply failure (voltage, fluid pressure, etc.) in propul-sion plant remote control is to activate an alarm at the con-trol position. In the event of remote control system failureand unless the Society considers it impracticable, the presetspeed and direction of thrust are to be maintained untillocal control is in operation. This applies in particular in thecase of loss of electric, pneumatic or hydraulic supply to thesystem.

4.1.4 Propulsion machinery orders from the navigationbridge shall be indicated in the main machinery controlroom, and at the manoeuvring platform.

4.1.5 The control shall be performed by a single controldevice for each independent propeller, with automatic per-formance of all associated services, including, where neces-sary, means of preventing overload of the propulsionmachinery. Where multiple propellers are designed to oper-ate simultaneously, they must be controlled by one controldevice.

4.1.6 Indicators shall be fitted on the navigation bridge, inthe main machinery control room and at the manoeuvringplatform, for:

• propeller speed and direction of rotation in the case offixed pitch propellers; and

• propeller speed and pitch position in the case of con-trollable pitch propellers.

4.1.7 The main propulsion machinery shall be providedwith an emergency stopping device on the navigationbridge which shall be independent of the navigation bridgecontrol system.

In the event that there is no reaction to an order to stop,provision is to be made for an alternative emergency stop.This emergency stopping device may consist of a simpleand clearly marked control device, for example a push-but-ton. This fitting is to be capable of suppressing the propellerthrust, whatever the cause of the failure may be.

4.2 Remote control from navigating bridge

4.2.1 Where propulsion machinery is controlled from thenavigating bridge, the remote control is to include an auto-matic device such that the number of operations to be car-ried out is reduced and their nature is simplified and suchthat control is possible in both the ahead and astern direc-tions. Where necessary, means for preventing overload andrunning in critical speed ranges of the propulsion machin-ery is to be provided.

Note 1: Arrangements which are not in compliance with the provi-sions of this Article may be considered for the following ships:

• ships less than 24 m in length

• cargo ships less than 500 tons gross tonnage

• ships to be assigned restricted navigation notations

• non-propelled units.

4.2.2 On board ships fitted with remote control, direct con-trol of the propulsion machinery is to be provided locally.The local direct control is to be independent from theremote control circuits, and takes over any remote controlwhen in use.

4.2.3 Each local control position, including partial control(e.g. local control of controllable pitch propellers orclutches) is to be provided with means of communicationwith the remote control position. The local control positionsare to be independent from remote control of propulsionmachinery and continue to operate in the event of a black-out (see [4.2.1], Note 1 in [4.2.1]).

4.2.4 Remote control of the propulsion machinery shall bepossible only from one location at a time; at such locationsinterconnected control positions are permitted.

4.2.5 The transfer of control between the navigating bridgeand machinery spaces shall be possible only in the mainmachinery space or the main machinery control room. Thesystem shall include means to prevent the propelling thrustfrom altering significantly, when transferring control fromone location to another (see [4.2.1], Note 1 in [4.2.1]).

4.2.6 At the navigating bridge, the control of the routinemanoeuvres for one line of shafting is to be performed by asingle control device: a lever, a handwheel or a push-buttonboard. However each mechanism contributing directly tothe propulsion, such as the engine, clutch, automatic brakeor controllable pitch propeller, is to be able to be individu-ally controlled, either locally or at a central monitoring andcontrol position in the engine room (see [4.2.1], Note 1 in[4.2.1]).

4.2.7 Remote starting of the propulsion machinery is to beautomatically inhibited if a condition exists which maydamage the machinery, e.g. shaft turning gear engaged,drop of lubrication oil pressure or brake engaged.

4.2.8 As a general rule, the navigating bridge panels are notto be overloaded by alarms and indications which are notrequired.

4.2.9 Automation systems shall be designed in a mannerwhich ensures that threshold warning of impending orimminent slowdown or shutdown of the propulsion systemis given to the officer in charge of the navigational watch intime to assess navigational circumstances in an emergency.In particular, the systems shall control, monitor, report, alertand take safety action to slowdown or stop propulsionwhile providing the officer in charge of the navigationalwatch an opportunity to manually intervene, except forthose cases where manual intervention will result in totalfailure of the engine and/or propulsion equipment within ashort time, for example in the case of overspeed.


Pt C, Ch 3, Sec 2

4.3 Automatic control

4.3.1 The requirements in [3] are applicable. In addition,the following requirements are to be considered, if relevant.

4.3.2 Main turbine propulsion machinery and, where appli-cable, main internal combustion propulsion machinery andauxiliary machinery shall be provided with automatic shut-off arrangements in the case of failures such as lubricatingoil supply failure which could lead rapidly to completebreakdown, serious damage or explosion.

4.3.3 The automatic control system is to be designed on afail safe basis, and, in the event of failure, the system is tobe adjusted automatically to a predetermined safe state.

4.3.4 Operations following any setting of the bridge controldevice (including reversing from the maximum ahead ser-vice speed in case of emergency) are to take place in anautomatic sequence and with acceptable time intervals, asprescribed by the manufacturer.

4.3.5 For steam turbines, a slow turning device is to be pro-vided which operates automatically if the turbine is stoppedlonger than admissible. Discontinuation of this automaticturning from the bridge is to be possible.

4.4 Automatic control of propulsion and manoeuvring units

4.4.1 When the power source actuating the automatic con-trol of propelling units fails, an alarm is to be triggered. Insuch case, the preset direction of thrust is to be maintainedlong enough to allow the intervention of engineers. Failingthis, minimum arrangements, such as stopping of the shaftline, are to be provided to prevent any unexpected reverseof the thrust. Such stopping may be automatic or ordered bythe operator, following an appropriate indication.

4.5 Clutches

4.5.1 Where the clutch of a propulsion engine is operatedelectrically, pneumatically or hydraulically, an alarm is tobe given at the control station in the event of loss of energy;as far as practicable, this alarm is to be triggered while it isstill possible to operate the equipment (see [4.2.1], Note 1in [4.2.1]).

4.5.2 When only one clutch is installed, its control is to befail-set. Other arrangements may be considered in relationto the configuration of the propulsion machinery.

4.6 Brakes

4.6.1 Automatic or remote controlled braking is to be pos-sible only if:

• propulsion power has been shut off

• the turning gear is disconnected

• the shaftline speed (r.p.m.) is below the threshold statedby the builder (see [4.2.1], Note 1 in [4.2.1]).

5 Communications

5.1 Communications between navigating bridge and machinery space

5.1.1 At least two independent means are to be providedfor communicating orders from the navigating bridge to theposition in the machinery space or in the control room fromwhich the speed and the direction of the thrust of the pro-pellers are normally controlled; one of these is to be anengine room telegraph, which provides visual indication ofthe orders and responses both in the machinery space andon the navigating bridge, with audible alarm mismatchbetween order and response.

5.1.2 Appropriate means of communication shall be pro-vided from the navigating bridge and the engine room toany other position from which the speed and direction ofthrust of the propellers may be controlled. The secondmeans for communicating orders is to be fed by an indepen-dent power supply and is to be independent of other meansof communication.

5.1.3 Where the main propulsion system of the ship is con-trolled from the navigating bridge by a remote control sys-tem, the second means of communication may be the samebridge control system.

5.1.4 The engine room telegraph is required in any case,even if the remote control of the engine is foreseen, irre-spective of whether the engine room is attended. An alarmis to be given at the navigation bridge in the event of failureof power supply to the engine room telegraph.

For ships assigned with a restricted navigation notationthese requirements may be relaxed at the Society's discre-tion.

5.2 Engineers’ alarm

5.2.1 An engineers' alarm shall be provided to be operatedfrom the engine control room or at the manoeuvring plat-form as appropriate, and shall be clearly audible in the engi-neers' accommodation

6 Remote control of valves

6.1

6.1.1 The following requirements are applicable to valveswhose failure could impair essential services.

6.1.2 Failure of the power supply is not to permit a valve tomove to an unsafe condition.

6.1.3 An indication is to be provided at the remote controlstation showing the actual position of the valve or whetherthe valve is fully open or fully closed. This indication maybe omitted for quick-closing valves.

6.1.4 When valves are remote controlled, a secondarymeans of operating them is to be provided which may bemanual control.


Pt C, Ch 3, Sec 2

7 Alarm system

7.1 General requirements

7.1.1 Alarms are to be visual and audible and are to beclearly distinguishable, in the ambient noise and lighting inthe normal position of the personnel, from any other sig-nals.

7.1.2 Sufficient information is to be provided for properhandling of alarms.

7.1.3 The alarm system is to be of the self-check type; fail-ure within the alarm system, including the outside connec-tion, is to activate an alarm. The alarm circuits are to beindependent from each other. All alarm circuits are to beprotected so as not to endanger each other.

7.2 Alarm functions

7.2.1 Alarm activationAlarms are to be activated when abnormal conditionsappear in the machinery, which need the intervention ofpersonnel on duty, and on the automatic change-over, whenstandby machines are installed.

An existing alarm is not to prevent the indication of any fur-ther fault.

7.2.2 Acknowledgement of alarmThe acknowledgment of an alarm consists in manuallysilencing the audible signal and additional visual signals(e.g. rotating light signals) while leaving the visual signal onthe active control station. Acknowledged alarms are to beclearly distinguishable from unacknowledged alarms.Acknowledgement should not prevent the audible signal tooperate for new alarm.

Alarms shall be maintained until they are accepted andvisual indications of individual alarms shall remain until thefault has been corrected, when the alarm system shall auto-matically reset to the normal operating condition.

Acknowledgement of alarms is only to be possible at theactive control station.

Alarms, including the detection of transient faults, are to bemaintained until acknowledgement of the visual indication.

Acknowledgement of visual signals is to be separate foreach signal or common to a limited group of signals.Acknowledgement is only to be possible when the user hasvisual information on the alarm condition for the signal orall signals in a group.

7.2.3 Locking of alarmsManual locking of separate alarms may be accepted whenthis is clearly indicated.

Locking of alarm and safety functions in certain operatingmodes (e.g. during start-up or trimming) is to be automati-cally disabled in other modes.

7.2.4 Time delay of alarmsIt is to be possible to delay alarm activation in order toavoid false alarms due to normal transient conditions (e.g.during start-up or trimming).

7.2.5 Transfer of responsibility

Where several alarm control stations located in differentspaces are provided, responsibility for alarms is not to betransferred before being acknowledged by the receivinglocation. Transfer of responsibility is to give an audiblewarning. At each control station it is to be indicated whichlocation is in charge.

8 Safety system

8.1 Design

8.1.1 System failures

A safety system is to be designed so as to limit the conse-quence of failures. It is to be constructed on the fail-to-safety principle.

The safety system is to be of the self-check type; as a rule,failure within the safety system, including the outside con-nection, is to activate an alarm.

8.2 Function

8.2.1 Safety activation

The safety system is to be activated automatically in theevent of identified conditions which could lead to damageof associated machinery or systems, such that:

• normal operating conditions are restored (e.g. by thestarting of the standby unit), or

• the operation of the machinery is temporarily adjustedto the prevailing abnormal conditions (e.g. by reducingthe output of the associated machinery), or

• the machinery is protected, as far as possible, from criti-cal conditions by shutting off the fuel or power supply,thereby stopping the machinery (shutdown), or appro-priate shutdown.

8.2.2 Safety indication

When the safety system has been activated, it is to be possi-ble to trace the cause of the safety action. This is to beaccomplished by means of a central or local indication.

When a safety system is made inoperative by a manualoverride, this is to be clearly indicated at correspondingcontrol stations.

Automatic safety actions are to activate an alarm at pre-defined control stations.

8.3 Shutdown

8.3.1 For shutdown systems of machinery, the followingrequirements are to be applied:

• when the system has stopped a machine, the latter is notto be restarted automatically before a manual reset ofthe safety system has been carried out

• the shutdown of the propulsion system is to be limitedto those cases which could lead to serious damage,complete breakdown or explosion.


Pt C, Ch 3, Sec 2

8.4 Standby systems

8.4.1 For the automatic starting system of the standby units,the following requirements are to be applied:

• faults in the electrical or mechanical system of the run-ning machinery are not to prevent the standby machin-ery from being automatically started

• when a machine is on standby, ready to be automati-cally started, this is to be clearly indicated at its controlposition

• the change-over to the standby unit is to be indicated bya visual and audible alarm

• means are to be provided close to the machine, to pre-vent undesired automatic or remote starting (e.g. whenthe machine is being repaired)

• automatic starting is to be prevented when conditionsare present which could endanger the standby machine.

8.5 Testing

8.5.1 The safety systems are to be tested in accordancewith the requirements in Ch 3, Sec 6.


Pt C, Ch 3, Sec 3

SECTION 3 COMPUTER BASED SYSTEMS

1 General requirements

1.1 General

1.1.1 The characteristics of the system are to be compatiblewith the intended applications, under normal and abnormalprocess conditions. The response time for alarm function isto be less than 5 seconds.

1.1.2 When systems under control are required to be dupli-cated and in separate compartments, this is also to apply tocontrol elements within computer based systems.

1.1.3 As a rule, computer based systems intended foressential services are to be type approved.

1.2 System type approval

1.2.1 The type approval is to cover the hardware and basicsoftware of the system. The type approval requirements aredetailed in Ch 3, Sec 6. A list of the documents to be sub-mitted is provided in Ch 3, Sec 1.

1.3 System operation

1.3.1 The system is to be protected so that authorised per-sonnel only can modify any setting which could alter thesystem.

1.3.2 Modification of the configuration, set points orparameters is to be possible without complex operationssuch as compilation or coded data insertion.

1.3.3 Program and data storage of the system is to bedesigned so as not to be altered by environmental condi-tions, as defined in Ch 2, Sec 2, [1], or loss of the powersupply.

1.4 System reliability

1.4.1 System reliability is to be documented as required inCh 3, Sec 1, [2.3.4].

1.4.2 When used for alarm, safety or control functions, thehardware system design is to be on the fail safe principle.

1.5 System failure

1.5.1 In the event of failure of part of the system, theremaining system is to be brought to a downgraded opera-ble condition.

1.5.2 A self-monitoring device is to be implemented so asto check the proper function of hardware and software inthe system. This is to include a self-check facility of input/output cards, as far as possible.

1.5.3 The failure and restarting of computer based systemsshould not cause processes to enter undefined or criticalstates.

1.6 System redundancy

1.6.1 If it is demonstrated that the failure of the system,which includes the computer based system, leads to a dis-ruption of the essential services, a secondary independentmeans, of appropriate diversity, is to be available to restorethe adequate functionality of the service.

2 Hardware

2.1 General

2.1.1 The construction of systems is to comply with therequirements of Ch 3, Sec 4.

2.2 Housing

2.2.1 The housing of the system is to be designed to facethe environmental conditions, as defined in Ch 2, Sec 2,[1], in which it will be installed. The design will be such asto protect the printed circuit board and associated compo-nents from external aggression. When required, the coolingsystem is to be monitored, and an alarm activated when thenormal temperature is exceeded.

2.2.2 The mechanical construction is to be designed towithstand the vibration levels defined in Ch 2, Sec 2,depending on the applicable environmental condition.

3 Software

3.1 General

3.1.1 The basic software is to be developed in consistentand independent modules.A self-checking function is to be provided to identify failureof software module.

When hardware (e.g. input /output devices, communicationlinks, memory, etc.) is arranged to limit the consequences offailures, the corresponding software is also to be separatedin different software modules ensuring the same degree ofindependence.

3.1.2 Computer based systems are to be configured withtype approved software according to Ch 3, Sec 6, [2.3].

3.1.3 Application software is to be tested in accordancewith Ch 3, Sec 6, [3.3].

3.1.4 Loading of software, when necessary, is to be per-formed in the aided conversational mode.


Pt C, Ch 3, Sec 3

3.1.5 Software versions are to be solely identified by num-ber, date or other appropriate means. Modifications are notto be made without also changing the version identifier. Arecord of changes is to be maintained and made availableupon request of the Society.

3.2 Software development quality

3.2.1 Software development is to be carried out accordingto a quality plan defined by the builder and records are tobe kept. The standard ISO 9000-1, or equivalent interna-tional standard, is to be taken as guidance for the qualityprocedure. The quality plan is to include the test procedurefor software and the results of tests are to be documented.

4 Data transmission link

4.1 General

4.1.1 The performance of the network transmissionmedium (transfer rate and time delay) is to be compatiblewith the intended application.

4.1.2 When the master /slave configuration is installed, themaster terminal is to be indicated on the other terminals.

4.2 Hardware support

4.2.1 The data transmission is to be self-checked, regardingboth the network transmission medium and the inter-faces/connections.

The data communication link is to be automatically startedwhen power is turned on, or restarted after loss of power.

4.2.2 The choice of transmission cable is to be madeaccording to the environmental conditions. Particular atten-tion is to be given to the level characteristics required forelectromagnetic interferences.

4.2.3 The installation of transmission cables is to complywith the requirements stated in Ch 2, Sec 11. In addition,the routing of transmission cables is to be chosen so as to bein less exposed zones regarding mechanical, chemical orEMI damage. As far as possible, the routing of each cable isto be independent of any other cable. These cables are notnormally allowed to be routed in bunches with other cableson the cable tray.

4.2.4 The coupling devices are to be designed, as far aspracticable, so that in the event of a single fault, they do notalter the network function. When a failure occurs, an alarmis to be activated.

Addition of coupling devices is not to alter the networkfunction.

Hardware connecting devices are to be chosen, when pos-sible, in accordance with international standards.

When a computer based system is used with a non-essentialsystem and connected to a network used for essential sys-tems, the coupling device is to be of an approved type.

4.3 Transmission software

4.3.1 The transmission software is to be so designed thatalarm or control data have priority over any other data. Forcontrol data, the transmission time is not to jeopardise effi-ciency of the functions.

4.3.2 The transmission protocol is preferably to be chosenamong international standards.

4.3.3 A means of transmission control is to be providedand designed so as to verify the completion of the datatransmitted (CRC or equivalent acceptable method). Whencorrupted data is detected, the number of retries is to belimited so as to keep an acceptable global response time.The duration of the message is to be such that it does notblock the transmission of other stations.

4.4 Transmission operation

4.4.1 When a hardware or software transmission failureoccurs, an alarm is to be activated. A means is to be pro-vided to verify the activity of transmission and its properfunction (positive information).

4.5 Redundant network

4.5.1 Where two or more essential functions are using thesame network, redundant networks are required accordingto the conditions mentioned in [1.6.1].

4.5.2 Switching of redundant networks from one to theother is to be achieved without alteration of the perfor-mance.

4.5.3 When not in operation, the redundant network is tobe permanently monitored, so that any failure of either net-work may be readily detected. When a failure occurs in onenetwork, an alarm is to be activated.

4.5.4 In redundant networks, the two networks are to bemutually independent. Failure of any common componentsis not to result in any degradation in performance.

4.5.5 When redundant data communication links arerequired, they are to be routed separately, as far as practica-ble.

5 Man-machine interface

5.1 General

5.1.1 The design of the operator interface is to follow ergo-nomic principles. The standard IEC 60447 Man-machineinterface or equivalent recognised standard may be used.

5.2 System functional indication

5.2.1 A means is to be provided to verify the activity of thesystem, or subsystem, and its proper function.


Pt C, Ch 3, Sec 3

5.2.2 A visual and audible alarm is to be activated in theevent of malfunction of the system, or subsystem. Thisalarm is to be such that identification of the failure is simpli-fied.

5.3 Input devices

5.3.1 Input devices are to be positioned such that the oper-ator has a clear view of the related display.

The operation of input devices, when installed, is to be log-ical and correspond to the direction of action of the con-trolled equipment.

The user is to be provided with positive confirmation ofaction.

Control of essential functions is only to be available at onecontrol station at any time. Failing this, conflicting controlcommands are to be prevented by means of interlocks and/or warnings.

5.3.2 When keys are used for common/important controls,and several functions are assigned to such keys, the activefunction is to be recognisable.

If use of a key may have unwanted consequences, provisionis to be made to prevent an instruction from being executedby a single action (e.g. simultaneous use of 2 keys, repeateduse of a key, etc.).

Means are to be provided to check validity of the manualinput data into the system (e.g. checking the number ofcharacters, range value, etc.).

5.3.3 If use of a push button may have unwanted conse-quences, provision is to be made to prevent an instructionfrom being executed by a single action (e.g. simultaneoususe of 2 push buttons, repeated use of push buttons, etc.).Alternatively, this push button is to be protected againstaccidental activation by a suitable cover, or use of a pullbutton, if applicable.

5.4 Output devices

5.4.1 VDU’s (video display units) and other output devicesare to be suitably lighted and dimmable when installed inthe wheelhouse. The adjustment of brightness and colour ofVDU’s is to be limited to a minimum discernable level.

When VDU’s are used for alarm purposes, the alarm signal,required by the Rules, is to be displayed whatever the otherinformation on the screen. The alarms are to be displayedaccording to the sequence of occurrence.

When alarms are displayed on a colour VDU, it is to bepossible to distinguish alarm in the event of failure of a pri-mary colour.

The position of the VDU is to be such as to be easily read-able from the normal position of the personnel on watch.The size of the screen and characters is to be chosenaccordingly.

When several control stations are provided in differentspaces, an indication of the station in control is to be dis-played at each control station. Transfer of control is to beeffected smoothly and without interruption to the service.

5.5 Workstations

5.5.1 The number of workstations at control stations is tobe sufficient to ensure that all functions may be providedwith any one unit out of operation, taking into account anyfunctions which are required to be continuously available.

5.5.2 Multifunction workstations for control and displayare to be redundant and interchangeable.

5.5.3 The choice of colour, graphic symbols, etc. is to beconsistent in all systems on board.

5.6 Computer dialogue

5.6.1 The computer dialogue is to be as simple and self-explanatory as possible.

The screen content is to be logically structured and showonly what is relevant to the user.

Menus are to be organised so as to have rapid access to themost frequently used functions.

5.6.2 A means to go back to a safe state is always to beaccessible.

5.6.3 A clear warning is to be displayed when using func-tions such as alteration of control condition, or change ofdata or programs in the memory of the system.

5.6.4 A ‘wait’ indication is to warn the operator when thesystem is executing an operation.

6 Integrated systems

6.1 General

6.1.1 Operation with an integrated system is to be at leastas effective as it would be with individual, stand aloneequipment.

6.1.2 Failure of one part (individual module, equipment orsubsystem) of the integrated system is not to affect the func-tionality of other parts, except for those functions directlydependant on information from the defective part.

6.1.3 A failure in connection between parts, cards connec-tions or cable connections is not to affect the independentfunctionality of each connected part.

6.1.4 Alarm messages for essential functions are to havepriority over any other information presented on the display.

7 Expert system

7.1

7.1.1 The expert system software is not to be implementedon a computer linked with essential functions.

7.1.2 Expert system software is not to be used for directcontrol or operation, and needs human validation by per-sonnel on watch.


Pt C, Ch 3, Sec 3

8 System testing

8.1

8.1.1 The system tests are to be carried out according to Ch3, Sec 6.

8.1.2 All alterations of a system (hardware and software)are to be tested and the results of tests documented.

9 System maintenance

9.1 Maintenance

9.1.1 System maintenance is to be planned and docu-mented.

9.1.2 Remote software maintenance may be considered oncase by case basis.


Pt C, Ch 3, Sec 4

SECTION 4 CONSTRUCTIONAL REQUIREMENTS

1 General

1.1 General

1.1.1 Automation systems are to be so constructed as:• to withstand the environmental conditions the environ-

mental conditions, as defined in Ch 2, Sec 2, [1], inwhich they operate

• to have necessary facilities for maintenance work.

1.2 Materials

1.2.1 Materials are generally to be of the flame-retardanttype.

1.2.2 Connectors are to be able to withstand standardvibrations, mechanical constraints and corrosion conditionsas given in Ch 3, Sec 6.

1.3 Component design

1.3.1 Automation components are to be designed to sim-plify maintenance operations. They are to be so constructedas to have:

• easy identification of failures

• easy access to replaceable parts

• easy installation and safe handling in the event ofreplacement of parts (plug and play principle) withoutimpairing the operational capability of the system, as faras practicable

• facility for adjustment of set points or calibration

• test point facilities, to verify the proper operation ofcomponents.

1.4 Environmental and supply conditions

1.4.1 The environmental and supply conditions are speci-fied in Ch 3, Sec 1. Specific environmental conditions are tobe considered for air temperature and humidity, vibrations,corrosion from chemicals and mechanical or biologicalattacks.

2 Electrical and/or electronic systems

2.1 General

2.1.1 Electrical and electronic equipment is to comply withthe requirements of Part C, Chapter 2 and Part C, Chapter 3.

2.1.2 A separation is to be done between any electricalcomponents and liquids, if they are in a same enclosure.Necessary drainage will be provided where liquids arelikely to leak.

2.1.3 When plug-in connectors or plug-in elements areused, their contacts are not to be exposed to excessivemechanical loads. They are to be provided with a lockingdevice.

2.1.4 All replaceable parts are to be so arranged that it isnot possible to connect them incorrectly or to use incorrectreplacements. Where this not practicable, the replacementparts as well as the associated connecting devices are to beclearly identified. In particular, all connection terminals areto be properly tagged. When replacement cannot be carriedout with the system on, a warning sign is to be provided.

2.1.5 Forced cooling systems are to be avoided. Whereforced cooling is installed, an alarm is to be provided in theevent of failure of the cooling system.

2.1.6 The interface connection is to be so designed toreceive the cables required. The cables are to be chosenaccording to Ch 2, Sec 3.

2.2 Electronic system

2.2.1 Printed circuit boards are to be so designed that theyare properly protected against the normal aggressionexpected in their environment.

2.2.2 Electronic systems are to be constructed takingaccount of electromagnetic interferences.

Special precautions are to be taken for:

• measuring elements such as the analogue amplifier oranalog/digital converter; and

• connecting different systems having different ground ref-erences.

2.2.3 The components of electronic systems (printed circuitboard, electronic components) are to be clearly identifiablewith reference to the relevant documentation.

2.2.4 Where adjustable set points are available, they are tobe readily identifiable and suitable means are to be pro-vided to protect them against changes due to vibrations anduncontrolled access.

2.2.5 The choice of electronic components is to be madeaccording to the normal environmental conditions, in par-ticular the temperature rating.

2.2.6 All stages of fabrication of printed circuit boards areto be subjected to quality control. Evidence of this control isto be documented.

2.2.7 Burn-in tests or equivalent tests are to be performed.


Pt C, Ch 3, Sec 4

2.2.8 The programmable components are to be clearlytagged with the program date and reference.

Components are to be protected against outside alterationwhen loaded.

2.3 Electrical system

2.3.1 Cables and insulated conductors used for internalwiring are to be at least of the flame-retardant type, and areto comply with the requirements in Part C, Chapter 2.

2.3.2 If specific products (e.g. oil) are likely to come intocontact with wire insulation, the latter is to be resistant tosuch products or properly shielded from them, and to com-ply with the requirements in Part C, Chapter 2.

3 Pneumatic systems

3.1

3.1.1 Pneumatic automation systems are to comply withCh 1, Sec 10, [17].

3.1.2 Pneumatic circuits of automation systems are to beindependent of any other pneumatic circuit on board.

4 Hydraulic systems

4.1

4.1.1 Hydraulic automation systems are to comply with Ch1, Sec 10, [14].

4.1.2 Suitable filtering devices are to be incorporated intothe hydraulic circuits.

4.1.3 Hydraulic circuits of automation systems are to beindependent of any other hydraulic circuit on board.

5 Automation consoles

5.1 General

5.1.1 Automation consoles are to be designed on ergo-nomic principles. Handrails are to be fitted for safe opera-tion of the console.

5.2 Indicating instruments

5.2.1 The operator is to receive feed back information onthe effects of his orders.

5.2.2 Indicating instruments and controls are to bearranged according to the logic of the system in control. Inaddition, the operating movement and the resulting move-ment of the indicating instrument are to be consistent witheach other.

5.2.3 The instruments are to be clearly labelled. Wheninstalled in the wheelhouse, all lighted instruments of con-soles are to be dimmable, where necessary.

5.3 VDU’s and keyboards

5.3.1 VDU’s in consoles are to be located so as to be easilyreadable from the normal position of the operator. The envi-ronmental lighting is not to create any reflection whichmakes reading difficult.

5.3.2 The keyboard is to be located to give easy accessfrom the normal position of the operator. Special precau-tions are to be taken to avoid inadvertent operation of thekeyboard.


Pt C, Ch 3, Sec 5

SECTION 5 INSTALLATION REQUIREMENTS

1 General

1.1

1.1.1 Automation systems are to be installed taking intoaccount:

• the maintenance requirements (test and replacement ofsystems or components)

• the influence of EMI. The IEC 60533 standard is to betaken as guidance

• the environmental conditions corresponding to thelocation in accordance with Ch 2, Sec 1and Ch 2, Sec3, [6].

1.1.2 Control stations are to be arranged for the conven-ience of the operator.

1.1.3 Automation components are to be properly fitted.Screws and nuts are to be locked, where necessary.

2 Sensors and components

2.1 General

2.1.1 The location and selection of the sensor is to be doneso as to measure the actual value of the parameter. Temper-ature, vibration and EMI levels are to be taken into account.When this is not possible, the sensor is to be designed towithstand the local environment.

2.1.2 The enclosure of the sensor and the cable entry are tobe appropriate to the space in which they are located.

2.1.3 Means are to be provided for testing, calibration andreplacement of automation components. Such means are tobe designed, as far as practicable, so as to avoid perturba-tion of the normal operation of the system.

2.1.4 A tag number is to identify automation componentsand is to be clearly marked and attached to the component.These tag numbers are to be collected on the instrument listmentioned in Ch 3, Sec 1, Tab 1.

2.1.5 Electrical connections are to be arranged for easyreplacement and testing of sensors and components. Theyare to be clearly marked.

2.1.6 Low level signal sensors are to be avoided. Wheninstalled they are to be located as close as possible toamplifiers, so as to avoid external influences. Failing this,the wiring is to be provided with suitable EMI protectionand temperature correction.

2.2 Temperature elements

2.2.1 Temperature sensors, thermostats or thermometersare to be installed in a thermowell of suitable material, topermit easy replacement and functional testing. The ther-mowell is not to significantly modify the response time ofthe whole element.

2.3 Pressure elements

2.3.1 Three-way valves or other suitable arrangements areto be installed to permit functional testing of pressure ele-ments, such as pressure sensors, pressure switches, withoutstopping the installation.

2.3.2 In specific applications, where high pulsations ofpressure are likely to occur, a damping element, such as acapillary tube or equivalent, is to be installed.

2.4 Level switches

2.4.1 Level switches fitted to flammable oil tanks, or similarinstallations, are to be installed so as to reduce the risk offire.

3 Cables

3.1 Installation

3.1.1 Cables are to be installed according to the require-ments in Ch 2, Sec 12, [7].

3.1.2 Suitable installation features such as screening and/ortwisted pairs and/or separation between signal and othercables are to be provided in order to avoid possible interfer-ence on control and instrumentation cables.

3.1.3 Specific transmission cables (coaxial cables, twistedpairs, etc.) are to be routed in specific cable-ways andmechanically protected to avoid loss of any important trans-mitted data. Where there is a high risk of mechanical dam-age, the cables are to be protected with pipes or equivalent.

3.1.4 The cable bend radius is to be in accordance with therequirements of Ch 2, Sec 12, [7.2].

For mineral insulated cables, coaxial cables or fibre opticcables, whose characteristics may be modified, special pre-cautions are to be taken according to the manufacturer’sinstructions.

3.2 Cable terminations

3.2.1 Cable terminations are to be arranged according tothe requirements in Part C, Chapter 2. Particular attention isto be paid to the connections of cable shields. Shields are to


Pt C, Ch 3, Sec 5

be connected only at the sensor end when the sensor isearthed, and only at the processor end when the sensor isfloating.

3.2.2 Cable terminations are to be able to withstand theidentified environmental conditions (shocks, vibrations, saltmist, humidity, etc.).

3.2.3 Terminations of all special cables such as mineralinsulated cables, coaxial cables or fibre optic cables are tobe arranged according to the manufacturer’s instructions.

4 Pipes

4.1

4.1.1 For installation of piping circuits used for automationpurposes, see the requirements in Ch 1, Sec 10.

4.1.2 As far as practicable, piping containing liquids is notto be installed in or adjacent to electrical enclosures (see Ch3, Sec 4, [2.1.2]).

4.1.3 Hydraulic and pneumatic piping for automation sys-tems is to be marked to indicate its function.

5 Automation consoles

5.1 General

5.1.1 Consoles or control panels are to be located so as toenable a good view of the process under control, as far aspracticable. Instruments are to be clearly readable in theambient lighting.

5.1.2 The location is to be such as to allow easy access formaintenance operations.


Pt C, Ch 3, Sec 6

SECTION 6 TESTING

1 General

1.1 General

1.1.1 Automation systems are to be tested for typeapproval, at works and on board, when required. Tests areto be carried out under the supervision of a Surveyor of theSociety.

1.1.2 The type testing conditions for electrical, control andinstrumentation equipment, computers and peripherals aredescribed in [2].

1.1.3 Automation systems are to be inspected at works,according to the requirements of [3], in order to check thatthe construction complies with the Rules.

1.1.4 Automation systems are to be tested when installedon board and prior to sea trials, to verify their performanceand adaptation on site, according to [4].

2 Type approval

2.1 General

2.1.1 The following requirements are applicable, but notconfined, to all electrical, control and instrumentation sys-tems which are intended to be type approved for use inmarine applications. In particular, they apply to control,protection, safety devices and internal communication.

2.1.2 The necessary documents to be submitted, prior totype testing, are listed in Ch 3, Sec 1, [2.4.1]. The typeapproval of automation systems refers to hardware typeapproval or software type approval, as applicable.

2.2 Hardware type approval

2.2.1 Hardware type approval of automation systems isobtained subject to the successful outcome of the testsdescribed in Tab 1. These tests are to demonstrate the abilityof the equipment to function as intended under the speci-fied test conditions.Vibration and salt mist testing may be performed on differ-ent specimens, where applicable.

Reset of the automation system is accepted between eachtest, where necessary.

2.2.2 The extent of testing (i.e. selection and sequence ofcarrying out tests and number of pieces to be tested) is to bedetermined upon examination and evaluation of the equip-ment or component subject to testing, giving due regards toits intended usage.Equipment is to be tested in its normal position if otherwisenot specified in the test specification.

Vibration and salt mist testing may be performed on differ-ent specimens, where applicable.

Reset of the automation system is accepted between eachtest, where necessary.

2.2.3 The following additional tests may be required,depending on particular manufacturing or operational con-ditions:• mechanical endurance test• temperature shock test (e.g. 12 shocks on exhaust gas

temperature sensors from 20°C ± 5°C to maximum tem-perature of the range)

• immersion test• oil resistance test• shock test.

The test procedure is to be defined with the Society in eachcase.

Table 1 : Type tests

N° Test Procedure (6) Test parameters Other information

1 Visualinspection

− − • drawings, design data

2 Performance test

Manufacturer perfor-mance test programmebased upon specifica-tion and relevant rulerequirements

• standard atmosphere conditions• temperature: 25°C ± 10°C• relative humidity: 60% ± 30%• air pressure: 96 KPa ± 10 KPa

• confirmation that operation is in accor-dance with the requirements specified forparticular automatic systems or equipment

• checking of self-monitoring features• checking of specified protection against an

access to the memory• checking against effect of unerroneous use

of control elements in the case of computersystems


Pt C, Ch 3, Sec 6

3 Power supply failure

− • 3 interruptions during 5 minutes• switching- off time 30 s each case

• verification of the specified action of theequipment on loss and restoration of sup-ply in accordance with the system design

• verification of possible corruption of pro-gramme or data held in programmableelectronic systems, where applicable

• the time of 5 minutes may be exceeded ifthe equipment under test needs a longertime for start up, e.g. booting sequence

• for equipment which requires booting, oneadditional power supply interruption dur-ing booting to be performed

4a Electric A.C. power supply variations

− COMBINATION

Voltage variation permanent

Frequency varia-tion permanent

+ 6%+ 6%– 10%– 10%

+ 5%– 5%– 5%+ 5%

voltage transient frequency transient

1,5 s+ 20%– 20%

5 s+ 10%– 10%

4b Electric D.C. power supply variations

− Voltage tolerance continuous: ± 10%Voltage cyclic variation: 5%Voltage ripple: 10%Electric battery supply:• +30% to –25% for equipment con-

nected to charging battery or asdetermined by the charging/dis-charging characteristics, includingripple voltage from the chargingdevice

• +20% to –25% for equipment notconnected to the battery duringcharging

4c Pneumatic and hydraulic power supply variations

− Pressure: ± 20%Duration: 15 minutes

5 Dry heat IEC Publication 60068-2-2

• Temperature: 55°C ± 2°CDuration: 16 hours, or

• Temperature: 70°C ± 2°CDuration: 2 hours (see (1))

• equipment operating during conditioningand testing

• functional test during the last hour at thetest temperature

6 Damp heat IEC Publication 60068-2-30 Test Db

Temperature: 55°CHumidity: 95%Duration: 2 cycles (12 + 12 hours)

• measurement of insulation resistancebefore test

• equipment operating during the completefirst cycle and switched off during secondcycle except for functional test

• functional test during the first 2 hours ofthe first cycle at the test temperature andduring the last 2 hours of the second cycleat the test temperature

• recovery at standard atmosphere condi-tions

• insulation resistance measurements andperformance test



Pt C, Ch 3, Sec 6

7 Vibration IEC Publication 60068-2-6 Test Fc

• 2 Hz ± 3/0 Hz to 13,2 Hz amplitude: ± 1mm

• 13,2 Hz to 100 Hz acceleration: ± 0,7 g

For severe vibration conditions suchas, e. g., on diesel engines, air com-pressors, etc.:• 2,0 Hz to 25 Hz

amplitude: ± 1,6 mm• 25 Hz to 100 Hz

acceleration: ± 4,0 gNote: Very special conditions mayexist for example on exhaust mani-folds of diesel engines especially formedium and high speed engines.Values may be required to be in thesecases:• 40 Hz to 2000 Hz• acceleration: ± 10,0 g at 600°C

• duration 90 minutes at 30 Hz in case of noresonance condition

• duration 90 minutes at each resonance fre-quency at which Q ≥ 2 is recorded

• during the vibration test, functional testsare to be carried out

• tests to be carried out in three mutuallyperpendicular planes

• it is recommended as a guidance that Qdoes not exceed 5

• duration 120 minutes where sweep test isto be carried out instead of discrete fre-quency test and a number of resonant fre-quencies is detected close to each other.Sweep over a restricted frequency rangebetween 0.8 and 1.2 times the critical fre-quencies can be used where appropriate.Note: Critical frequency is a frequency atwhich the equipment being tested mayexhibit:• malfunction and/or performance dete-

rioration• mechanical resonances and/or other

response effects occur, e.g. chatter

8 Inclination IEC Publication 60092-504

Static 22,5° a) inclined to the vertical at an angle of atleast 22,5°

b) inclined to at least 22,5° on the other sideof the vertical and in the same plane as in a)

c) inclined to the vertical at an angle of atleast 22,5° in plane at right angles to thatused in a)

d) inclined to at least 22,5° on the other sideof the vertical and in the same plane as in c)

Note: The period of testing in each positionshould be sufficient to fully evaluate the behav-iour of the equipment

Dynamic 22,5° Using the directions defined in a) to d) above,the equipment is to be rolled to an angle of22,5° each side of the vertical with a period of10 secondsThe test in each direction is to be carried outfor not less than 15 minutes

Note: These inclination tests are normally notrequired for equipment with no moving parts.

9 Insulation resistance

Ratedsupply voltage

Testvoltage

Minimum insulation resistance • insulation resistance test is to be carriedout before and after: damp heat test, coldtest, salt mist test and high voltage test

• between all phases and earth, and whereappropriate between the phases

Note: Certain components, e. g. for EMC pro-tection, may be required to be disconnectedfor this test

before after

Un ≤ 65 V 2 x Un min. 24 V

10 Mohms 1,0 Mohms

Un > 65V 500 V 100 Mohms 10 Mohms



Pt C, Ch 3, Sec 6

10 High voltage Rated voltageUn

Test voltage(A.C. voltage 50 or 60Hz)

• separate circuits are to be tested againsteach other and all circuits connected witheach other tested against earth

• printed circuits with electronic compo-nents may be removed during the test

• period of application of the test voltage:1 minute

Note: Certain components, e. g. printed cir-cuits with electronic components, may berequired to be disconnected for this test

Up to 65 V 2 x Un + 500 V

66 V to 250 V 1500 V

251 V to 500 V 2000 V

501 V to 690 V 2500 V

11 Cold IEC Publication 60068-2-1

• Temperature: +5°C ± 3°CDuration: 2 hours, or

• Temperature: –25°C ± 3°CDuration: 2 hours (see (2))

• initial measurement of insulation resistance• equipment not operating during condition-

ing and testing except for functional test• functional test during the last hour at the

test temperature• insulation resistance measurement and the

functional test after recovery

12 Salt mist IEC Publication 60068-2-52 Test Kb

Four spraying periods with a storage of seven days after each

• initial measurement of insulation resistanceand initial functional test

• equipment not operating during condition-ing

• functional test on the 7th day of each stor-age period

• insulation resistance measurement andperformance test 4 to 6h after recovery (see(3))

13 Electrostatic discharge

IEC 61000-4-2 Contact discharge: 6 kVAir discharge: 8 kVInterval between single discharges:1 sec.No. of pulses: 10 per polarityAccording to level 3 severity standard

• to simulate electrostatic discharge as mayoccur when persons touch the appliance

• the test is to be confined to the points andsurfaces that can normally be reached bythe operator

• performance criterion B (see (4))

14 Radiated RadioFrequency

IEC 61000-4-3 Frequency range:80 MHz to 2 GHzModulation**: 80% AM at 1000HzField strength: 10V/mFrequency sweep rate:≤ 1,5.10-3 decades/s (or 1% / 3 sec)According to level 3 severity standard

• to simulate electromagnetic fields radiatedby different transmitters

• the test is to be confined to the appliancesexposed to direct radiation by transmittersat their place of installation

• performance criterion A (see (5))** If, for tests of equipment, an input signalwith a modulation frequency of 1000 Hz isnecessary, a modulation frequency of 400 Hzshould be chosen

15 ConductedAudioFrequency

A.C.:• Frequency range: rated frequency

to 200th harmonic• Test voltage (rms): 10% of supply

to 15th harmonic reducing to 1%at 100th harmonic and maintainthis level to the 200th harmonic,min 3 V r.m.s, max. 2 W

D.C.:• Frequency range: 50 Hz - 10 kHz• Test voltage (rms): 10% of supply,

max. 2 W

• to simulate distortions in the power supplysystem generated, for instance, by elec-tronic consumers and coupled in as har-monics

• see figure “Test set-up” (see (8))• performance criterion A (see (5))



Pt C, Ch 3, Sec 6

16 ConductedRadioFrequency

IEC 61000-4-6 AC, DC, I/O ports and signal/control linesFrequency range: 150 kHz - 80 MHzAmplitude: 3 V rms (see (7))Modulation***: 80% AM at 1000 HzFrequency sweep range:≤ 1,5.10-3 decades/s (or 1% / 3sec.)According to level 2 severity standard

• to simulate electromagnetic fields coupledas high frequency into the test specimenvia the connecting lines

• performance criterion A (see (5))*** If, for tests of equipment, an input signalwith a modulation frequency of 1000 Hz isnecessary, a modulation frequency of 400 Hzshould be chosen

17 Burst/ Fast Transients

IEC 61000-4-4 Single pulse time: 5ns (between 10% and 90% value)Single pulse width: 50 ns (50% value)Amplitude (peak): 2 kV line on power supply port/earth; 1 kV on I/O data control and communication ports (coupling clamp)Pulse period: 300 msBurst duration: 15 msDuration/polarity: 5 minAccording to level 3 severity standard

• arcs generated when actuating electricalcontacts

• interface effect occurring on the powersupply, as well as at the external wiring ofthe test specimen


18 Surge / Slow Transient

IEC 61000-4-5 Pulse rise time: 1,2 µVs (between 10% and 90% value)Pulse width: 50 µVs (50% value)Amplitude (peak): 1 kV line/earth; 0,5kV line/lineRepetition rate: ≥ 1 pulse/minNo of pulses: 5 per polarityApplication: continuousAccording to level 2 severity standard

• to simulate interference generated, forinstance, by switching “ON” or “OFF” highpower inductive consumers

• test procedure in accordance with figure10 of the standard for equipment wherepower and signal lines are identical


19 RadiatedEmission

CISPR 16-1, 16-2 • For equipment installed in the bridge and deck zone:

• procedure in accordance with the standardbut distance 3 m between equipment andantennaFrequency

range (MHz):0,15 - 0,300,30 - 3030 - 2000except for:156 - 165

Limits:(dBµV/m)

80- 5050- 34

54

24

• For equipment installed in thegeneral power distribution zone:

Frequencyrange: (MHz)0,150 - 0,168

0,168 - 3030 - 100

100 - 2000except for:156 - 165

Limits:(dBµV/m)80 - 7575 - 5060 - 54

54

24



Pt C, Ch 3, Sec 6

20 ConductedEmission

CISPR 16-1, 16-2 • For equipment installed in the bridge and deck zone:

Frequencyrange:

10 - 150 kHz150 - 350 kHz0,35 - 30 MHz

Limits:(dBµV)96 - 5060 - 50

50

• For equipment installed in thegeneral power distribution zone:

Frequency range:

10 - 150 kHz150 - 500 kHz0,50 - 30 MHz

Limits:(dBµV)

120 - 6979 73

21 Flameretardant

IEC 60092-101 or IEC 60695-11-5

Flame application: 5 times 15 s each Interval between each application: 15 s or 1 time 30 s

• the burnt out or damaged part of the speci-men by not more than 60mm long

• no flame, no incandescence or in the eventof a flame or incandescence being present,it shall extinguish itself within 30 s of theremoval of the needle flame without fullcombustion of the test specimen

• any dripping material shall extinguish itselfin such a way as not to ignite a wrappingtissue. The drip height is 200 mm ± 5 mm

(1) Equipment to be mounted in consoles, housing etc. together with other equipment are to be tested with 70°C.(2) For equipment installed in non-weather protected locations or cold locations, test is to be carried out at –25°C.(3) Salt mist test is to be carried out for equipment installed in weather exposed areas.(4) Performance criterion B: (for transient phenomena): The Equipment Under Test shall continue to operate as intended after the

tests. No degradation of performance or loss of function is allowed as defined in the technical specification published by theManufacturer. During the test, degradation or loss of function or performance which is self recoverable is however allowed butno change of actual operating state or stored data is allowed.

(5) Performance criterion A (for continuous phenomena): The EUT shall continue to operate as intended during and after the test. Nodegradation of performance or loss of function is allowed as defined in relevant equipment standard and the technical specifica-tion published by the Manufacturer.

(6) Column 3 indicates the testing procedure which is normally to be applied. However, equivalent testing procedure may beaccepted by the Society provided that what is required in the other columns is fulfilled.

(7) For equipment installed on the bridge and deck zone, the test levels shall be increased to 10V rms for spot frequencies in accor-dance with IEC 60945 at 2,3,4,6.2, 8.2, 12.6, 16.5, 18.8, 22, 25 MHz.

(8) Figure - Test set-up for Conducted Low Frequency - Refer to IEC Publication 60945 (1996).


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Pt C, Ch 3, Sec 6

2.3 Software type approval

2.3.1 Software of computer based systems are to beapproved in accordance with Information Note “SoftwareAssessment for Shipboard Computer Based System” (NI425).

Type approval consists of an assessment of the developmentquality and verification of test results.

Assessment certificate may be issued at the request of themanufacturer when approval is granted.

2.3.2 Software are to be approved in association with hard-ware. Reference of software and hardware should be speci-fied in type approval certificate.

2.3.3 Basic software of standard type used as tools for oper-ation of a computer based system may be accepted withouttype approval at the discretion of the Society.

2.4 Navigational and radio equipment

2.4.1 The test conditions as specified in the IEC 60945(marine navigational and radiocommunication equipmentand systems - general requirements, methods of testing andrequired test results) may be applied.

2.5 Loading instruments

2.5.1 Loading instrument approval consists of:

• approval of hardware according to [2.2], unless twocomputers are available on board for loading calcula-tions only

• approval of basic software according to [2.3]

• approval of application software, consisting in data veri-fication which results in the Endorsed Test Conditionaccording to Part B

• installation testing according to [4].

2.6 Oil mist detection system

2.6.1 Type test of oil mist detection system are to be carriedout according to Ch 3, App 1.

3 Acceptance testing

3.1 General

3.1.1 Acceptance tests are generally to be carried out at themanufacturer’s facilities before the shipment of the equip-ment, when requested.

Acceptance tests refer to hardware and software tests asapplicable.

3.2 Hardware testing

3.2.1 Hardware acceptance tests include, where applicable:

• visual inspection

• operational tests and, in particular:

- tests of all alarm and safety functions

- verification of the required performance (range, cali-bration, repeatability, etc.) for analogue sensors

- verification of the required performance (range, setpoints, etc.) for on/off sensors

- verification of the required performance (range,response time, etc.) for actuators

- verification of the required performance (full scale,etc.) for indicating instruments

• endurance test (burn-in test or equivalent)

• high voltage test

• hydrostatic tests.

Additional tests may be required by the Society.

3.2.2 Final acceptance will be granted subject to:

• the results of the tests listed in [3.2.1]

• the type test report or type approval certificate.

3.3 Software testing

3.3.1 Software acceptance tests of computer based systemsare to be carried out to verify their adaptation to their useon board, and concern mainly the application software.

3.3.2 The software modules of the application software areto be tested individually and subsequently subjected to anintegration test. The test results are to be documented and tobe part of the final file. It is to be checked that:

• the development work has been carried out in accor-dance with the plan

• the documentation includes the proposed test, theacceptance criteria and the result.

Repetition tests may be required to verify the consistency oftest results.

3.3.3 Software acceptance will be granted subject to:

• examination of the available documentation

• a functional test of the whole system.

The Society may ask for additional tests of systems whichare part of safety systems or which integrate several func-tions.

4 On board tests

4.1 General

4.1.1 On board tests are to be carried out on automationsystems associated with essential services to verify theircompliance with the Rules, by means of visual inspectionand the performance and functionality according to Tab 2.

When completed, automation systems are to be such that asingle failure, for example loss of power supply, is not toresult in a major degradation of the propulsion or steering ofthe ship. In addition, a blackout test is to be carried out toshow that automation systems are continuously supplied.

Upon completion of on board tests, test reports are to bemade available to the Surveyor.


Pt C, Ch 3, Sec 6

Table 2 : On board tests

Equipment Nature of tests

Electronic equipment

Main hardware functionality

Analogue sensors

Signal calibration, trip set point adjustment

On/off sensors Simulation of parameter to verify and record the set points

Actuators Checking of operation in whole range and performance (response time, pumping)

Reading instruments

Checking of calibration, full scale and standard reference value


Pt C, Ch 3, App 1

APPENDIX 1 TYPE TESTING PROCEDURE FOR CRANKCASE OIL MIST DETECTION AND ALARM EQUIPMENT

1 General

1.1 Scope

1.1.1 This Appendix is to specify the tests required to dem-onstrate that crankcase oil mist detection and alarm equip-ment intended to be fitted to diesel engines.

Note 1: This test procedure is also applicable to oil mist detectionand alarm equipment intended for gear cases.

1.2 Recognised standard

1.2.1 IACS Unified Requirement E10 Type Test Specifica-tion.

1.3 Purpose

1.3.1 The purpose of type testing crankcase oil mist detec-tion and alarm equipment is to verify:

• the functionality of the system

• the effectiveness of the oil mist detectors

• the accuracy of oil mist detectors

• the alarm set points

• time delays between oil mist leaving the source andalarm activation

• functional failure detection

• the influence of optical obscuration on detection.

1.4 Test facilities

1.4.1 Test houses carrying out type testing of crankcase oilmist detection and alarm equipment are to satisfy the fol-lowing criteria:

• A full range of facilities for carrying out the environmen-tal and functionality tests required by this procedureshall be available and be acceptable to the Society

• The test house that verifies the functionality of theequipment is to be equipped so that it can control,measure and record oil mist concentration levels interms of mg/l to an accuracy of ± 10% in accordancewith this procedure.

2 Testing

2.1 Equipment testing

2.1.1 The range of tests for the alarm/monitoring panel is toinclude the following:

a) functional tests described in [2.2]

b) electrical power supply failure test

c) power supply variation test

d) dry heat test

e) damp heat test

f) vibration test

g) EMC test

h) insulation resistance test

i) high voltage test

j) static and dynamic inclinations, if moving parts are con-tained.

2.1.2 The range of tests for the detectors is to include thefollowing:

a) functional tests described in [2.2]

b) electrical power supply failure test

c) power supply variation test

d) dry heat test

e) damp heat test

f) vibration test

g) EMC test where susceptible

h) insulation resistance test

i) high voltage test

j) static and dynamic inclinations.

2.2 Functional tests

2.2.1 All tests to verify the functionality of crankcase oilmist detection and alarm equipment are to be carried out inaccordance with [2.2.2] to [2.2.6] with an oil mist concen-tration in air, known in terms of mg/l to an accuracy of± 10%.

2.2.2 The concentration of oil mist in the test chamber is tobe measured in the top and bottom of the chamber andthese concentrations are not to differ by more than 10%.See also [2.4.1], item a).


Pt C, Ch 3, App 1

2.2.3 The oil mist monitoring arrangements are to be capa-ble of detecting oil mist in air concentrations of between 0and 10% of the lower explosive limit (LEL) or between 0and a percentage corresponding to a level not less thantwice the maximum oil mist concentration alarm set point.Note 1: The LEL corresponds to an oil mist concentration ofapproximately 50 mg/l (~4,1% weight of oil in air mixture).

2.2.4 The alarm set point for oil mist concentration in air isto provide an alarm at a maximum level corresponding tonot more than 5% of the LEL or approximately 2,5 mg/l.

2.2.5 Where alarm set points can be altered, the means ofadjustment and indication of set points are to be verifiedagainst the equipment manufacturer’s instructions.

2.2.6 Where oil mist is drawn into a detector via pipingarrangements, the time delay between the sample leavingthe crankcase and operation of the alarm is to be deter-mined for the longest and shortest lengths of pipes recom-mended by the manufacturer. The pipe arrangements are tobe in accordance with the manufacturer’s instructions/rec-ommendations.

2.2.7 Detector equipment that is in contact with the crank-case atmosphere and may be exposed to oil splash andspray from engine lubricating oil is to be demonstrated asbeing such, that openings do not occlude or becomeblocked under continuous oil splash and spray conditions.Testing is to be in accordance with arrangements proposedby the manufacturer and agreed by the Society.

2.2.8 Detector equipment may be exposed to water vapourfrom the crankcase atmosphere which may affect the sensi-tivity of the equipment and it is to be demonstrated thatexposure to such conditions will not affect the functionaloperation of the detector equipment. Where exposure towater vapour and/or water condensation has been identi-fied as a possible source of equipment malfunctioning, test-ing is to demonstrate that any mitigating arrangements suchas heating are effective. Testing is to be in accordance witharrangements proposed by the manufacturer and agreed bythe Society.Note 1: This testing is in addition to that required by [2.1.2], item e)and is concerned with the effects of condensation caused by thedetection equipment being at a lower temperature than the crank-case atmosphere.

2.3 Detectors and alarm equipment to be tested

2.3.1 The detectors and alarm equipment selected for thetype testing are to be selected from the manufacturer’s nor-mal production line by the Surveyor witnessing the tests.

2.3.2 Two detectors are to be tested. One is to be tested inclean condition and the other in a condition representingthe maximum level of lens obscuration specified by themanufacturer.

2.4 Method

2.4.1 The following requirements for oil mist generationare to be satisfied at type testing:

a) Oil mist is to be generated with suitable equipmentusing an SAE 80 monograde mineral oil or equivalentand supplied to a test chamber having a volume of notless than 1m3. The oil mist produced is to have a maxi-mum droplet size of 5 µm.

Note 1: The oil droplet size is to be checked using the sedimenta-tion method.

b) The oil mist concentrations used are to be ascertainedby the gravimetric deterministic method or equivalent.

Note 2: For this test, the gravimetric deterministic method is a proc-ess where the difference in weight of a 0,8 µm pore size mem-brane filter is ascertained from weighing the filter before andafter drawing 1 litre of oil mist through the filter from the oilmist test chamber. The oil mist chamber is to be fitted with arecirculating fan.

c) Samples of oil mist are to be taken at regular intervalsand the results plotted against the oil mist detector out-put. The oil mist detector is to be located adjacent towhere the oil mist samples are drawn off.

d) The results of a gravimetric analysis are consideredinvalid and are to be rejected if the resultant calibrationcurve has an increasing gradient with respect to the oilmist detection reading. This situation occurs when insuf-ficient time has been allowed for the oil mist to becomehomogeneous. Single results that are more than 10%below the calibration curve are to be rejected. This situ-ation occurs when the integrity of the filter unit has beencompromised and not all of the oil is collected on thefilter paper.

e) The filters require to be weighed to a precision of 0,1mgand the volume of air/oil mist sampled to 10 ml.

2.4.2 The testing is to be witnessed by authorised personnelfrom the Society.

2.4.3 Oil mist detection equipment is to be tested in theorientation (vertical, horizontal or inclined) in which it isintended to be installed on an engine or gear case as speci-fied by the equipment manufacturer.

2.4.4 Type testing is to be carried out for each type of oilmist detection and alarm equipment for which a manufac-turer seeks approval. Where sensitivity levels can beadjusted, testing is to be carried out at the extreme and mid-point level settings.

2.5 Assessment

2.5.1 Assessment of oil mist detection equipment after test-ing is to address the following:

• The equipment to be tested is to have evidence ofdesign appraisal/approval.

• Details of the detection equipment to be tested are to berecorded such as name of manufacturer, type designa-tion, oil mist concentration assessment capability andalarm settings.

• After completing the tests, the detection equipment is tobe examined and the condition of all componentsascertained and documented. Photographic records ofthe monitoring equipment condition are to be taken andincluded in the report.


Pt C, Ch 3, App 1

2.6 Design series qualification

2.6.1 The approval of one type of detection equipment maybe used to qualify other devices having identical construc-tion details. Proposals are to be submitted for consideration.

2.7 Test report

2.7.1 The test house is to provide a full report whichincludes the following information and documents:

• test specification

• details of equipment tested

• results of tests.

2.8 Acceptance

2.8.1 Acceptance of crankcase oil mist detection equip-ment is at the discretion of the Society based on theappraisal plans and particulars and the test house report ofthe results of type testing.

2.8.2 The following information is to be submitted to theSociety for acceptance of oil mist detection equipment andalarm arrangements:• Description of oil mist detection equipment and system

including alarms• Copy of the test house report identified in [2.7]• Schematic layout of engine oil mist detection arrange-

ments showing location of detectors/sensors and pipingarrangements and dimensions

• Maintenance and test manual which is to include thefollowing information:- intended use of equipment and its operation- functionality tests to demonstrate that the equipment

is operational and that any faults can be identifiedand corrective actions notified

- maintenance routines and spare parts recommenda-tions

- limit setting and instructions for safe limit levels- where necessary, details of configurations in which

the equipment is and is not to be used.
