Section 10 Electrical equipment

10.1.1 The electrical contacts of air circuit-breakers are to be visually inspected and maintained in accordance with the manufacturer’s recommendations by suitably qualified and trained personnel. Appropriate maintenance records are to be made available to the attending Surveyor on request.

10.1.2 Where the craft is fitted with harmonic filters, the harmonic distortion level is to be measured annually and after any modification to the craft electrical distribution system or associated consumers. As a minimum, harmonic distortion measurements are to be taken at the main busbar under seagoing conditions, as close to the annual survey as possible, and readings are to be recorded when the greatest amount of distortion is indicated, by suitably qualified and trained personnel.

Records are to include which equipment was running and the filters that were in service, and these records are to be made available to the attending Surveyor on request.

10.1.3 The requirements of Pt 1, Ch 3, 2.2 Annual Surveys 2.2.16 and Pt 1, Ch 3, 3.2 Intermediate Surveys 3.2.4 are to be complied with as far as applicable.

10.2.1 An electrical insulation resistance test is to be made on the electrical equipment and cables. The installation may be sub-divided, or equipment which may be damaged disconnected, for the purpose of this test.

10.2.2 The fittings on the main and emergency switchboards, section boards and distribution boards are to be examined and over-current protective devices and fuses inspected to verify that they provide suitable protection for their respective circuits.

10.2.3 Generator circuit-breakers are to be tested, so far as is practicable, to verify that protective devices including preference tripping relays, if fitted, operate satisfactorily.

10.2.4 Air circuit-breakers for essential or emergency services and rated at 800 A and above are to be surveyed to ensure that the manufacturer’s recommended number of switching options has not been exceeded. See Vol 7, Pt 16, Ch 2, 7.3 Circuit-breakers 7.3.6. Where a breaker is not fitted with an automatic counter, a written record is to be kept.

10.2.5 The electric cables and their securing arrangements are to be examined, so far as is practicable, without undue disturbance of fixtures or casings unless opening up is considered necessary as a result of observation or of the tests required by Pt 1, Ch 3, 10.2 Complete Surveys 10.2.1.

10.2.6 The generator prime movers are to be surveyed as required by Pt 1, Ch 3, 8 Gas turbines - Detailed requirements and Pt 1, Ch 3, 9 Reciprocating internal combustion engines - Detailed requirements and the governing of the engines tested. The motors concerned with essential services together with associated control and switch gear are to be examined and if considered necessary, are to be operated, so far as is practicable, under working conditions. All generators and steering gear motors are to be examined and are to be operated under working conditions, though not necessarily under full load or simultaneously.

10.2.7 Where transformers or electrical apparatus associated with supplies to essential services are liquid-immersed, the Owner is to arrange for samples of the liquid to be taken and tested for dissolved gases, breakdown voltage, acidity and moisture by a competent authority, in accordance with the equipment manufacturer's requirements, and a certificate giving the test results is to be made available to the Surveyor on request.

10.2.8 Navigation light indicators are to be tried under working conditions, and correct operation on the failure of supply or failure of navigation lights verified.

10.2.9 The emergency sources of electrical power, where fitted, together with their automatic arrangements and associated circuits are to be tested.

10.2.10 Emergency lighting, transitional emergency lighting, supplementary emergency lighting, general emergency alarm and public address systems are to be tested as far as practicable.

10.2.11 Where the craft is electrically propelled, the propulsion motors, generators, propulsion transformers, propulsion conversion equipment, cables, harmonic filters, neutral earthing resistors, dynamic braking resistors and all ancillary electrical equipment that forms part of the propulsion drive and control system, exciters and ventilating plant (including coolers) associated therewith are to be surveyed, and the insulation resistance to earth is to be tested. Special attention is to be given to windings, commutators and slip-rings. Where practicable, the low voltage and high voltage windings of resin cast propulsion transformers are to be subjected to boroscopic inspection, to assess the physical condition of their insulation and for signs of mechanical and thermal damage. The operation of protective gear and alarm devices is to be checked, so far as is practicable. Insulating oil, if used, is to be tested in accordance with Pt 1, Ch 3, 10.2 Complete Surveys 10.2.7. Interlocks intended to prevent unsafe operations or unauthorised access are to be checked to verify that they are functioning correctly. Emergency overspeed governors are to be tested.

10.2.12 Where batteries with charging power higher than 2kW provide the source of power for any essential services, their installation, including charging and ventilation arrangements, is to be examined.

10.2.13 Sufficient battery capacity shall be verified for Lithium-Ion battery system installations used as the primary power source for emergency systems.

10.2.14 Where Lithium-Ion batteries with total system capacity exceeding 20 kWh are used as the primary power source for essential or emergency systems, a test of all required monitoring and safety functions shall be carried out.

10.2.15 A test of the safety functions in spaces or compartments containing Lithium-Ion batteries with total system capacity exceeding 20 kWh used as power source for essential and emergency services shall be carried out, i.e., fire detection and extinguishing, gas detection, ventilation etc. as applicable to the installation.