Rules for the Classification of Naval Ships

PART C - Machinery, Systems and Fire Protection

Chapters 2 3

NR 483.C2 DT R01 E November 2011

Marine Division 92571 Neuilly sur Seine Cedex France

Tel: + 33 (0)1 55 24 70 00 Fax: + 33 (0)1 55 24 70 25 Marine website: http://www.veristar.com Email: veristarinfo@bureauveritas.com

2011 Bureau Veritas - All rights reserved

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 OFNAVAL SHIPS

Part CMachinery, Systems and Fire Protection

Chapters 1 2 3 4

Chapter 1 MACHINERY

Chapter 2 ELECTRICAL INSTALLATIONSChapter 3 AUTOMATIONChapter 4 FIRE PROTECTION, DETECTION AND EXTINCTIONNovember 2011

CHAPTER 2ELECTRICAL INSTALLATIONS

Section 1 General1 Application 19

1.1 General1.2 References to other regulations and standards

2 Documentation to be submitted 202.1

3 Definitions 203.1 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 Certified safe-type equipment3.26 Environmental categories

Section 2 General Design Requirements1 Environmental conditions 24

1.1 General1.2 Ambient air temperatures1.3 Humidity1.4 Cooling water temperatures1.5 Salt mist1.6 Inclinations1.7 Vibrations1.8 ShockNovember 2011 Bureau Veritas Rules for Naval Ships 3

2 Quality of power supply 252.1 General2.2 A.c. distribution systems2.3 D.c. distribution systems2.4 Harmonic distortions

3 Electromagnetic susceptibility 263.1

4 Materials 264.1 General4.2 Insulating materials for windings4.3 Insulating materials for cables

5 Construction 265.1 General5.2 Degree of protection of enclosures

6 Protection against explosion hazard 276.1 Protection against explosive gas or vapour atmosphere hazard6.2 Protection against combustible dust hazard

Section 3 System Design1 Supply systems and characteristics of the supply 28

1.1 Supply systems1.2 Maximum voltages

2 Sources of electrical power 292.1 General2.2 Main source of electrical power2.3 Emergency source of electrical power2.4 Use of emergency generator in port

3 Distribution 313.1 Earthed distribution systems3.2 Insulated distribution systems3.3 General requirements for distribution systems3.4 Main distribution of electrical power3.5 Emergency distribution of electrical power3.6 Shore/Ship supply3.7 Supply of motors3.8 Specific requirements for special power services3.9 Power supply to heaters3.10 Power supply to lighting installations3.11 Special lighting services3.12 Navigation and signalling lights3.13 General emergency alarm system3.14 Public address system3.15 Combined general emergency alarm - public address system3.16 Control and indication circuits3.17 Power supply to the speed control systems of main propulsion engines3.18 Power supply to the speed control systems of generator sets4 Bureau Veritas Rules for Naval Ships November 2011

4 Degrees of protection of the enclosures 364.1 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 385.1 General

6 Environmental categories of the equipment 386.1 Environmental categories

7 Electrical protection 397.1 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 Localization of over-current 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 438.1 General

9 Electrical cables 439.1 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 conditions9.7 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 4810.1 Electrical equipment10.2 Electrical cables10.3 Electrical installations in battery rooms10.4 Electrical installations in paint stores10.5 Electrical installations in stores for welding gas (acetylene) bottlesNovember 2011 Bureau Veritas Rules for Naval Ships 5

Section 4 Rotating Machines1 Constructional and operational requirements for generators and motors 50

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

2 Special requirements for generators 502.1 Prime movers, speed governors and overspeed protection2.2 A.c. generators

3 Testing of rotating machines 513.1 General3.2 Shaft material3.3 Tests

4 Description of the test 524.1 Examination of the technical documentation, as appropriate, and visual

inspection4.2 Insulation resistance measurement4.3 Winding resistance measurement4.4 Verification of the voltage regulation system4.5 Rated load test and temperature rise measurements4.6 Overload/overcurrent tests4.7 Verification of steady short-circuit conditions4.8 Overspeed test4.9 Dielectric strength test4.10 No load test4.11 Verification of degree of protection4.12 Verification of bearings

Section 5 Transformers1 Constructional and operational requirements 54

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 552.1 General2.2 Tests on transformers

Section 6 Semiconductor Convertors1 Constructional and operational requirements 56

1.1 Construction1.2 Protection1.3 Parallel operation with other power sources1.4 Temperature rise1.5 Insulation test6 Bureau Veritas Rules for Naval Ships November 2011

2 Testing 572.1 General2.2 Tests on convertors

Section 7 Storage Batteries and Chargers1 Constructional requirements for batteries 58

1.1 General1.2 Vented batteries1.3 Valve-regulated sealed batteries1.4 Tests on batteries

2 Constructional requirements for chargers 582.1 Characteristics2.2 Tests on chargers

Section 8 Switchgear and Controlgear Assemblies1 Constructional requirements for main and emergency switchboards 60

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 622.1 Construction

3 Testing 623.1 General3.2 Inspection of equipment, check of wiring and electrical operation test3.3 High voltage test3.4 Measurement of insulation resistance

Section 9 Cables1 Constructional requirements 64

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 652.1 Type tests2.2 Routine testsNovember 2011 Bureau Veritas Rules for Naval Ships 7

Section 10 Miscellaneous Equipment1 Switchgear and controlgear, protective devices 66

1.1 General1.2 Circuit-breakers1.3 Protection devices

2 Lighting fittings 662.1 Applicable requirements2.2 Construction

3 Accessories 663.1 Applicable requirements3.2 Construction

4 Plug-and-socket connections 674.1 Applicable requirements

5 Heating and cooking appliances 675.1 Applicable requirements5.2 General5.3 Space heaters5.4 Cooking appliances5.5 Fuel oil and lube oil heaters5.6 Water heaters

Section 11 Location1 General 68

1.1 Location1.2 Areas with a risk of explosion

2 Main electrical system 682.1 Location in relation to the emergency system2.2 Main switchboard

3 Emergency electrical system 683.1 Spaces for the emergency source3.2 Location in relation to the main electrical system3.3 Emergency switchboard3.4 Emergency battery

4 Distribution boards 694.1 Distribution boards for cargo spaces and similar spaces4.2 Distribution board for navigation lights

5 Cable runs 695.1 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 circuits8 Bureau Veritas Rules for Naval Ships November 2011

6 Storage batteries 696.1 General6.2 Large vented batteries6.3 Moderate vented batteries6.4 Small vented batteries6.5 Ventilation

Section 12 Installation1 General 72

1.1 Protection against injury or damage caused by electrical equipment1.2 Protection against damage to electrical equipment1.3 Accessibility

2 Earthing of non-current carrying parts 722.1 Parts which are to be earthed2.2 Methods of earthing2.3 Earthing connections2.4 Connection to the ships structure2.5 Earthed distribution systems2.6 Aluminium superstructures

3 Rotating machines 733.1 General

4 Semiconductor convertors 734.1 Semiconductor power convertors

5 Vented type storage batteries 735.1 General5.2 Protection against corrosion

6 Switchgear and controlgear assemblies 746.1 Main switchboard6.2 Emergency switchboard6.3 Section boards and distribution boards

7 Cables 747.1 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 in the vicinity of radio equipment7.17 Cables for submerged bilge pumpsNovember 2011 Bureau Veritas Rules for Naval Ships 9

8 Various appliances 808.1 Lighting fittings8.2 Heating appliances8.3 Heating cables and tapes or other heating elements

Section 13 High Voltage Installations1 General 81

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

2 System design 812.1 Distribution2.2 Degrees of protection2.3 Insulation2.4 Protection

3 Rotating machinery 823.1 Stator windings of generators3.2 Temperature detectors3.3 Tests

4 Power transformers 834.1 General

5 Cables 835.1 General

6 Switchgear and controlgear assemblies 836.1 General6.2 Construction6.3 Auxiliary systems6.4 High voltage test

7 Installation 837.1 Electrical equipment7.2 Cables

Section 14 Electric Propulsion Plant1 General 85

1.1 Applicable requirements1.2 Operating conditions

2 Design of the propulsion plant 852.1 General2.2 Power supply2.3 Auxiliary machinery2.4 Electrical Protection2.5 Excitation of electric propulsion motor10 Bureau Veritas Rules for Naval Ships November 2011

3 Construction of rotating machines and semiconductor convertors 863.1 Ventilation3.2 Protection against moisture and condensate3.3 Rotating machines3.4 Semiconductor convertors

4 Control and monitoring 874.1 General4.2 Power plant control systems4.3 Indicating instruments 4.4 Alarm system4.5 Reduction of power

5 Installation 885.1 Ventilation of spaces5.2 Cable runs

6 Tests 886.1 Test of rotating machines

7 Specific requirements for PODs 897.1 General7.2 Rotating commutators7.3 Electric motors 7.4 Instrumentation and associated devices7.5 Additional tests

Section 15 Testing1 General 90

1.1 Rule application1.2 Insulation-testing instruments

2 Type approved components 902.1

3 Insulation resistance 903.1 Lighting and power circuits3.2 Internal communication circuits3.3 Switchboards3.4 Generators and motors

4 Earth 904.1 Electrical constructions4.2 Metal-sheathed cables, metal pipes or conduits

5 Operational tests 915.1 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 dropNovember 2011 Bureau Veritas Rules for Naval Ships 11

CHAPTER 3AUTOMATION

Section 1 General Requirements1 General 95

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

2 Documentation 962.1 General2.2 Documents to be submitted2.3 Documents for computer based system2.4 Documents for type approval of equipment

3 Environmental and supply conditions 973.1 General3.2 Power supply conditions

4 Materials and construction 984.1 General4.2 Type approved components

Section 2 Design Requirements1 General 99

1.1

2 Power supply of automation systems 992.1 General2.2 Electrical power supply

3 Control systems 993.1 General3.2 Local control3.3 Remote control systems3.4 Automatic control systems

4 Control of propulsion machinery 1004.1 Local control4.2 Remote control4.3 Remote control from navigating bridge4.4 Automatic control 4.5 Automatic control of propulsion and manoeuvring units4.6 Clutches4.7 Brakes

5 Remote control of valves 1015.1 12 Bureau Veritas Rules for Naval Ships November 2011

6 Alarm system 1016.1 General requirements6.2 Alarm functions

7 Safety system 1027.1 Design7.2 Function7.3 Shutdown7.4 Standby systems7.5 Testing

Section 3 Computer Based Systems1 General requirements 103

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

2 Hardware 1032.1 General2.2 Housing

3 Software 1033.1 General3.2 Software development quality

4 Data transmission link 1044.1 General4.2 Hardware support4.3 Transmission software 4.4 Transmission operation4.5 Redundant network

5 Man-machine interface 1045.1 General5.2 System functional indication5.3 Input devices5.4 Output devices5.5 Workstations5.6 Computer dialogue

6 Integrated systems 1056.1 General

7 System testing 1067.1

8 System maintenance 1068.1 November 2011 Bureau Veritas Rules for Naval Ships 13

Section 4 Constructional Requirements1 General 107

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

2 Electrical and/or electronic systems 1072.1 General2.2 Electronic system2.3 Electrical system

3 Pneumatic systems 1083.1

4 Hydraulic systems 1084.1

5 Automation consoles 1085.1 General5.2 Indicating instruments5.3 VDUs and keyboards

Section 5 Installation Requirements1 General 109

1.1

2 Sensors and components 1092.1 General2.2 Temperature elements2.3 Pressure elements

3 Cables 1093.1 Installation3.2 Cable terminations

4 Pipes 1104.1

5 Automation consoles 1105.1 General14 Bureau Veritas Rules for Naval Ships November 2011

Section 6 Testing1 General 111

1.1 General

2 Type approval 1112.1 General2.2 Hardware type approval2.3 Software type approval2.4 Loading instruments

3 Acceptance testing 1153.1 General3.2 Hardware testing3.3 Software testing

4 Commissioning 1164.1 GeneralNovember 2011 Bureau Veritas Rules for Naval Ships 15

16 Bureau Veritas Rules for Naval Ships November 2011

Part CMachinery, Systems and 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 TESTINGNovember 2011 Bureau Veritas Rules for Naval Ships 17

18 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 1SECTION 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 essential services.

The other parts of the installation are to be so designed asnot to introduce any malfunction to the ship and hazard topersonnel.

1.2 References to other regulations andstandards

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 recognized standards, are those currently inforce at the date of agreement for ship classification.

Table 1 : Documents to be submitted

No I/A (1) Document1 A Single line diagram of main power and lighting systems

2 A Electrical power balance

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

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

5 A Single line diagram and detailed diagram of the main switchboard

6 A Single line diagram and detailed diagram of the emergency switchboards

7 A Diagram of the most important section boards and motor control centres (above 100 kW)

8 A Diagram of the supply, monitoring and control systems of propulsion motors and generator prime movers

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

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

11 A Diagram of the general emergency alarm system and of the intercommunication systems requested in Ch 4, Sec8, [1.1.2]

12 A Detailed diagram of the navigation-light switchboard

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

14 A (2) Selectivity and coordination of the electrical protection15 A Single line diagram of electrical propulsion system

16 A Principles of control system and power supply of electrical propulsion system

17 A Alarm and monitoring system including, for electrical propulsion system: list of alarms and monitoring points power supply diagram.

18 A Safety system including, for electrical propulsion system: list of monitored parameters for safety system power supply diagram.

19 I (3) Arrangements and details of the propulsion control consoles and panels20 I (3) Arrangements and details of electrical coupling21 I (3) Arrangements and details of the frequency converters together with the justification of their characteristics22 I (3) Arrangements of the cooling system provided for the frequency converters and motor enclosure23 I (3) Measurements of voltage signal form for converters directly connected to high voltage (HV) network24 I (3) Computation of permanent and transitory voltage drops of LV and HV networks25 A (3) Test program for converters and rotating machines having rated power > 1 MW, dock and sea trials

(1) A: to be submitted for approvalI : to be submitted for information.

(2) for high voltage installations.(3) for electric propulsion installations.November 2011 Bureau Veritas Rules for Naval Ships 19

Pt C, Ch 2, Sec 12 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 sup-plier.

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.

Primary essential services are services such as:

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

at least one fire pump, when required to be permanentlyin operation.

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.

3.4 Secondary essential services

3.4.1 Secondary essential services are those services whichneed not necessarily be in continuous operation.

Secondary essential services are services such as:

windlasses

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

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 equipment

control, monitoring and safety for cargo containmentsystems

control, monitoring and safety devices/systems forequipment for secondary essential services.20 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 13.4.2 Services for habitability are those intended for mini-mum comfort conditions for people on board, and speciallyin engine control room, safety room and operation controlroom.

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 "single insulation system" does not imply that theinsulation must be one homogeneous piece. It may comprise sev-eral layers which cannot be tested singly as supplementary or basicinsulation.

3.12 Earthing3.12.1 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 habitablecondition

3.13.1 A condition under which the ship as a whole, themachinery, services, means and aids ensuring propulsion,ability to steer, safe navigation, pay load, fire and floodingsafety, internal and external communications and signals,means of escape, and emergency boat winches, as well asthe designed comfortable conditions of habitability are inworking order and functioning normally.

3.14 Emergency condition3.14.1 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 amain switchboard for distribution to all services necessaryfor maintaining the ship in normal operational and habit-able condition.

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 station3.17.1 The space in which a main source of electricalpower is situated.

3.18 Main switchboard

3.18.1 A switchboard which is directly supplied by a mainsource of electrical power and is intended to distribute elec-trical energy to the ships services.November 2011 Bureau Veritas Rules for Naval Ships 21

Pt C, Ch 2, Sec 13.19 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 electrical power and is intended todistribute electrical energy 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 electrical power supply system.

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 present,or may be expected to be present due to the presence ofvapours, gases, flammable dusts or explosives in quantitiessuch as to require special precautions for the construction,installation and use of electrical apparatus.

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 atmosphere ispresent continuously or is present for long periods

zone 1: an area in which an explosive gas atmosphere islikely to occur in normal operation

zone 2: an area in which an explosive gas atmosphere isnot 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 Certified safe-type equipment

3.25.1 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.

3.26 Environmental categories

3.26.1 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.

3.26.2 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.

Table 2 : EC Code

Table 3 : First 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 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 + 4522 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 1Table 4 : Second characteristic numeral

Secondcharacteristic

numeralBrief description of location Frequency range Hz

Displacement amplitude

(mm)

Acceleration amplitude g

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

from 2,0 to 13,2from 13,2 to 100

1,0

0,7

2 Masts from 2,0 to 13,2from 13,2 to 50

3,0

2,1

3 On air compressors, on diesel engines and similar from 2,0 to 25,0from 25,0 to 100

1,6

4,0November 2011 Bureau Veritas Rules for Naval Ships 23

Pt C, Ch 2, Sec 2SECTION 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), biological conditions, condi-tions dependent upon chemically active substances (e.g. saltmist) or mechanically active substances (e.g. dust or oil),mechanical conditions (e.g. vibrations or inclinations) and con-ditions dependent upon electromagnetic noise and interfer-ence, 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 + 40C instead of + 45C).

1.2.3 For ships classed for NBC service, adequate means ofrefrigeration are to be provided and systems have to with-stand the maximum temperature expected in NBC condition.

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 Cooling 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 cooling watertemperature (e.g. for ships operating outside the tropicalbelt, the maximum cooling water temperature may beassumed as equal to + 25C instead of + 32C).

1.5 Salt mist

1.5.1 The applicable salt mist content in the air is to be1 mg/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.The necessary damping elements on machinery supportswill be fitted to reach this level.

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.

1.8 Shock

1.8.1 When required by the Naval Authority and in generalfor front line ships, shock levels are to be evaluated.

Location Temperature range (C)

Enclosed spaces + 5 + 45

Inside consoles or fitted oncombustion engines and similar

+ 5 + 55

Air conditioned areas + 5 + 40

Exposed decks 25 + 45

Location Humidity

General 95% at 55C

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

Coolant Temperature range (C)

Sea water 0 + 3224 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 2Table 4 : Inclination of ship

Table 5 : Vibration levels

1.8.2 Electrical components are to be so designed, manu-factured and installed that they are capable of operating sat-isfactorily under shock conditions.

1.8.3 This capability may be achieved through their owncharacteristics or through particular installation arrange-ments.

2 Quality of power supply

2.1 General2.1.1 All electrical components are to be so designed andmanufactured that they are capable of operating satisfacto-rily under the variations of voltage, frequency and harmonicdistortion of the power supply specified from [2.2] to [2.4].

2.2 A.c. distribution systems2.2.1 For alternating current components the voltage andfrequency variations of power supply shown in Tab 6 are tobe assumed.

Table 6 : Voltage and frequency variationsof power supply in a.c.

2.3 D.c. distribution systems

2.3.1 For direct current components voltage variations ofpower supply shown in Tab 7 are to be assumed.

Table 7 : Voltage variations of power supply 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.

2.4 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 (3) static dynamic (4)

Machinery and equipment relative to main electrical power installation 15,0 22,5 5,0 7,5

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

22,5 22,5 10,0 10,0

Switchgear and associated electrical and electronic components and remote control systems (2)

22,5 22,5 10,0 10,0

(1) Athwartship and fore-and-aft angles may occur simultaneously in their most unfavourable combination.(2) No undesired switching operations or functional changes may occur up to an angle of inclination of 45.(3) The period of dynamic inclination may be assumed equal to 10 s.(4) The period of dynamic inclination may be assumed equal to 5 s.

LocationFrequency range

(Hz)Displacement

amplitude (mm)Accelerationamplitude g

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

from 2,0 to 13,2from 13,2 to 100

0,25

0,2

On air compressors, on diesel engines and similar from 2,0 to 25,0from 25,0 to 100

1,6

4,0

Masts from 2,0 to 13,2from 13,2 to 50

1,0

0,7

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%November 2011 Bureau Veritas Rules for Naval Ships 25

Pt C, Ch 2, Sec 22.4.2 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%.

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.

Figure 1 :

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.

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 recognized standards.

4.2 Insulating materials for windings4.2.1 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 cables4.3.1 See Ch 2, Sec 9, [1.3].

5 Construction

5.1 General5.1.1 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 3).

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.

5.2 Degree of protection of enclosures5.2.1 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 3.

10

5

1

0,11 3 10 15 100

U U

(%)

ClassMaximum continuous operating

temperature (C)

A 105

E 120

B 130

F 155

H 18026 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 25.2.2 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 [5.1.5].

6 Protection against explosion hazard

6.1 Protection against explosive gas orvapour atmosphere hazard

6.1.1 Electrical equipment intended for use in areas whereexplosive gas or vapour atmospheres may occur, is to be ofa "safe type" suitable for the relevant flammable atmosphereand 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) oil-immersed apparatus (see [6.1.2], Note 1): Ex(o)

Note 1: Only when required by the application.

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 die-lectric, or encapsulated.

6.2 Protection against combustible dusthazard

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 135C is considered adequate.November 2011 Bureau Veritas Rules for Naval Ships 27

Pt C, Ch 2, Sec 3SECTION 3 SYSTEM DESIGN

1 Supply systems and characteristicsof 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 neutral directly earthed orthrough impedance

three-phase four-wire neutral directly earthed orthrough impedance

single-phase two-wire insulated

single-phase two-wire with one phase earthed.

1.1.2 The hull return system of distribution is not to beused.

1.1.3 The requirement of [1.1.2] does not preclude underconditions approved by the Society the use of:

a) impressed current cathodic protective systems

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

1.1.4 For the supply systems in HV installations, see Ch 2,Sec 13.

1.1.5 When required by the Naval Authority, for the supplyof weapon system and shore supply, the STANAG standard1008 NAV is to be applied. Mainly, the distribution systemsto be of the three phase three wires with neutral insulated.

1.2 Maximum voltages

1.2.1 The maximum voltages for both alternating currentand direct current low-voltage systems of supply for theships 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.

Table 1 : Maximum voltages for various ship services

Use Maximum voltage V

For permanently installed andconnected to fixed wiring

Power equipmentCooking equipmentLightingSpace heaters in accommodation spacesControl (1), communication (including signal lamps) and instrumentationequipment

1000500250250250

For permanently installed andconnected by flexible cable

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

1000

For socket-outletssupplying

Portable appliances which are not hand-held during operation (e.g. refriger-ated containers) by flexible cablesPortable appliances and other consumers by flexible cablesEquipment requiring extra precaution against electric shock where an isolat-ing transformer is used to supply one appliance (2) (3)Equipment requiring extra precaution against electric shock with or withouta safety transformer (2) (3)

1000

250250

50

(1) For control equipment which is part of a power and heating installation (e.g. pressure or temperature switches for starting/stoppingmotors), the same maximum voltage as allowed for the power and heating equipment may be used provided that all componentsare 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.(3) Equipment located in narrow and wet spaces such as machinery spaces provided with bilge spaces.28 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 32 Sources of electrical power

2.1 General

2.1.1 Electrical installations are to be such that:a) All electrical auxiliary services necessary for maintain-

ing the ship in normal operational and habitable condi-tions will be assured without recourse to the emergencysource of electrical power

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, or other pay load consumers having pulseloads, particularly with regard to the effect of the magni-tude and duration of the transient voltage change pro-duced due to the maximum starting or pulse currentsand the power factor. The voltage drop due to such cur-rents 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 without recourse to theemergency source of electrical 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 theships auxiliary services, see Ch 2, Sec 14.

2.2.3 When only one main source of electrical power isprovided, it is to consist of at least two generating sets.The capacity of the main generating sets is to be such that inthe event of any one generating set being stopped it will stillbe possible to supply those services necessary to providenormal operational conditions.

Such capacity is, in addition, to be sufficient to start thelargest motor and to supply pay-load consumers havingpulse loads without causing any other motor to stop or hav-ing any adverse effect on other equipment in operation.

2.2.4 For the purpose of calculating the necessary capacity,it is essential to consider which consumers can be expectedto be in use simultaneously, in the various operational con-ditions of the ship.

For a duplicated service, one being supplied electricallyand the other non-electrically (see [2.2.4], Note 1) (e.g.driven by the main engine), the electrical capacity is notincluded in the above calculation.Note 1: It is assumed that the consumers not electrically driven arecapable to operate satisfactorily in all conditions.

2.2.5 The services in [2.2.4] do not include: thrusters not forming part of the main propulsion or

dynamic positioning system

refrigerators for air conditioning other than air refrigeratorsystems for satisfactory operation of essential services.

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 The arrangement of the ship's main sources 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.

2.2.8 Generators driven by the propulsion plant (shaft gen-erators) which are intended to operate at constant speed(e.g. a system where vessel speed and direction are con-trolled by varying propeller speed) may be accepted asforming part of the main source of electrical power if, in allsailing and manoeuvring conditions, and including the pro-peller being stopped, the capacity of these generators is suf-ficient to provide the electrical power to comply with[2.2.3] and all further requirements, especially those of[2.2.6]. They are to be not less effective and reliable thanthe independent generating sets.

2.2.9 Shaft generator installations which do not complywith the provisions of [2.2.8] 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.

2.2.10 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 so that with any onetransformer 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.

Where single phase transformers are used, only one spareelement is required for each different type of transformer ifspecial precautions are taken to rapidly replace the faultyone.

2.2.11 For ships having qualified automation systems, seePart E, Chapter 4.

2.2.12 For starting arrangements for main generating sets,see Ch 1, Sec 2, [3.1].November 2011 Bureau Veritas Rules for Naval Ships 29

Pt C, Ch 2, Sec 32.3 Emergency source of electrical power

2.3.1 Where the main sources of electrical power arelocated in two or more compartments that are not contigu-ous with each other and separated in such a way to ensurethe supply to the emergency services also in case of flood-ing of the maximum number of contiguous compartmentsaccording to stability regulation (see Part B), and whereeach source has its own independent self contained sys-tems, including power distribution and control systems suchthat a fire in any one of the compartments or other casualtyincluding the flooding of the maximum number of contigu-ous compartments according to stability regulation asabove, will not affect the power distribution from the othermain sources, or to the services required by [3.5.3], therequirement of this section will be satisfied without theadditional source of emergency electrical power (requiredby [2.3.2], provided that:

a) there is at least one generating set complying with therequirements from [2.3.5] to [2.3.15] and of sufficientcapacity to meet the requirements of [3.5.3] in at leasttwo non-contiguous (as prescribed above) compart-ments

b) the generator sets referred to in [2.3.1] (a) and their selfcontained systems are installed such that one of themremains operable after damage or flooding in any onecompartment.

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

2.3.3 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.

2.3.4 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.

2.3.5 The emergency source of electrical power shall becapable, having regard to starting currents and the transitorynature of certain loads, of supplying simultaneously at leastthe services stated in [3.5.3] for the period specified, if theydepend upon an electrical source for their operation.

2.3.6 The transitional source of emergency electricalpower, where required, is to be of sufficient capacity to sup-ply at least the services for the time stated in [3.5.6], if theydepend upon an electrical source for their operation.

2.3.7 An indicator shall be mounted in a suitable place, ina continuously manned control position (e.g. platform con-trol room), to indicate when the batteries constituting eitherthe emergency source of electrical power or the transitionalsource of emergency electrical power are being discharged.

2.3.8 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).

2.3.9 Where electrical power is necessary to restore pro-pulsion, 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 or the other means stored startingenergy is not to be directly used for starting the propulsionplant.

For steam ships, the 30 minute time limit given can be inter-preted as time from blackout/dead ship condition definedabove to light-off the first boiler.

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 [2.3.14],respectively.

2.3.13 Where the emergency source of electrical power isa generator, it shall be:

a) driven by a suitable prime mover with an independentsupply of fuel, having a flashpoint (closed cup test) ofnot less than 43C30 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 3b) started automatically upon failure of the electrical sup-ply to the emergency switchboard from the main sourceof electrical power and shall be automatically con-nected to the emergency switchboard; those servicesreferred to in [3.5.6] shall then be transferred automati-cally to the emergency generating set. The automaticstarting system and the characteristic of the prime movershall be such as to permit the emergency generator tocarry its full rated load as quickly as is safe and practica-ble, subject to a maximum of 45 s, and

c) provided with a transitional source of emergency elec-trical power according to [2.3.15].

2.3.14 Where here the emergency source of electricalpower is an 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 [3.5.6].

2.3.15 The transitional source of emergency electricalpower required by [2.3.13] c) shall consist of an accumula-tor battery which shall operate without recharging whilemaintaining the voltage of the battery throughout the dis-charge period within 12% above or below its nominal volt-age and be so arranged as to supply automatically in theevent of failure of either the main or emergency source ofelectrical power at least the services in [3.5.6] if theydepend upon an electrical source for their operation.

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 [3.5].

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 services.

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.

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 after theprotective devices (e.g. in automation systems or to avoidelectromagnetic disturbances), provision (e.g. d.c./d.c. con-vertors or transformers) is to be made such that currentunbalances do not occur in the individual poles or phases.

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 contin-uously monitoring the insulation level to earth (i.e. the val-ues of 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 convertors.November 2011 Bureau Veritas Rules for Naval Ships 31

Pt C, Ch 2, Sec 33.2.2 For high voltage systems see Ch 2, Sec 13.

3.3 General requirements for distributionsystems

3.3.1 The distribution system is to be such that the failure ofany single circuit will not endanger or impair essential ser-vices.

3.3.2 No common switchgear (e.g. contactors for emer-gency stop) is to be used between the switchboard's bus-bars and two duplicated essential services.

3.3.3 The system shall be so arranged that the electricalsupply will be maintained or immediately restored in thecase of loss of any one of the generators in service. Auto-matic restart of equipment necessary for propulsion andsteering and to ensure safety of the ship is also to be pro-vided.

3.3.4 Arrangements are to be provided to prevent overload-ing of the generating set(s) supplying the electrical powerthat is/are required to maintain the ship in a normal opera-tional and habitable condition.

On loss of electrical power, arrangements are to be madefor a standby generator set to be automatically started, auto-matically connected to the switchboard within 30 secondsafter loss of power, and essential services restarted in asshort a time as is practicable.

These load restart functions may be achieved by the actionsof suitably trained personnel but in ships with AUT-QAS,AUT-IAS notations the arrangements are to be automatic.

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

3.3.5 Automatic load shedding or other equivalent arrange-ments are to be provided to protect the generators againstsustained over-load.

3.3.6 The non-essential services, service for habitable con-ditions may be shed to ensure the connected generator setor generator sets are not overloaded.

3.4 Main distribution of electrical power

3.4.1 Where more than one main generator is connected toa main switchboard, the main bus-bar is to be divided intoat least two parts which are normally to be connected bycircuit breakers or other approved means such as circuitbreakers without tripping mechanisms or disconnectingswitches by means of which bus-bars can be split safely andeasily.

The connection of generating sets, 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.

The same applies in case of main switchboards supplied byone generating set and connected to another main switch-board, being this connection considered as a connection ofa second generator.

3.4.2 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 require-ment is satisfied when such units are supplied by separatecables from the a main switchboard or from two indepen-dent section boards.

3.4.3 A main electric lighting system, which is to provideillumination throughout those parts of the ship normallyaccessible to and used by personnel, is to be supplied fromthe main sources of electrical power.

3.5 Emergency distribution of electricalpower

3.5.1 The emergency switchboard shall be supplied duringnormal operation from the main switchboard by an inter-connector feeder which shall be adequately protected at themain 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.

3.5.2 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.

3.5.3 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 unless,when an electrical distribution by zones is adopted,alternative arrangements are provided by movablelamps having their own dedicated accumulator batteriesfor at least 3 hours operation that in normal conditionare continuously charged:

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 including platform controlroom and combat system control rooms, machinerycontrol rooms, and at each main and emergencyswitchboard

4) at all stowage positions for firemens 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 motors32 Bureau Veritas Rules for Naval Ships November 2011

Pt C, Ch 2, Sec 3c) for a period of 18 hours:

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

2) the radio installation and external communicationsystems required by SOLAS and or by the NavalAuthority

d) for a period of 18 hours:

1) all internal communication equipment as requiredin an emergency [3.5.4]

2) the shipborne navigational equipment as requiredby SOLAS and or by the Naval Authority, includingthose for flight assistance

3) the fire detection and fire alarm systems, and

4) intermittent operation of the daylight signallinglamp, the ships whistle, the manually operated callpoints and all internal signals (see [3.5.5]) 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:

1) one of the fire pumps required by the relevant provi-sions of Part C, Chapter 4

2) the automatic sprinkler pump, if any, and

3) the emergency bilge pump and all the equipmentessential for the operation of electrically poweredremote controlled bilge valves

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

g) for a period of half an hour, any watertight doorsrequired to be power operated together with their indi-cators and warning signals

h) equipment necessary for ship's self defence or a selec-tion of apparatus of the pay load to be defined case bycase by the Naval Authority.

3.5.4 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 for fire fighting and dam-age control

d) the means of communication for combat system opera-tion

e) the public address system.

3.5.5 Internal signals required in an emergency generallyinclude:

a) general alarm

b) watertight door alarm and indication system.

3.5.6 The transitional source of emergency electrical powershall supply for half an hour at least the following services ifthey depend upon an electrical source for their operation:

a) the lighting required by [3.5.3], 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 byindividual, automatically charged, relay operated accu-mulator lamps, and

b) all services required by [3.5.3], 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.

It is also to supply power to close the watertight doors, butnot necessarily all of them simultaneously, unless an inde-pendent temporary source of stored energy is provided andpowers the control, indication and alarm circuits, for half anhour.

3.6 Shore/Ship supply

3.6.1 Arrangements are to be made for supplying the elec-trical installation from a source on shore or elsewhere. Atleast a suitable connection box is to be installed on the shipin a convenient location to receive the flexible cable fromoutside.

3.6.2 Permanently fixed cables of adequate rating are to beprovided for connecting the box to the main distributionsystem.

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

3.6.4 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.

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

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

3.6.7 The shore connection is to be provided with an indi-cator at the main switchboard in order