Section 14 Electrical equipment

14.1.1 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.

14.1.2 Where harmonic filters are fitted, the harmonic distortion level is to be measured annually and after any modification to the 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 including the load on it and the filters that were in service. These records are to be made available to the attending Surveyor on request.

14.1.3 The requirements of Pt 1, Ch 3, 2.2 Annual Surveys and Pt 1, Ch 3, 3.3 Intermediate Surveys are to be complied with as far as applicable.

14.2.1 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.

14.2.2 The fittings on the main and emergency switchboard, 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.

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

14.2.4 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 Pt 6, 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.

14.2.5 The electric cables are to be examined, so far as 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, 14.2 Complete Surveys 14.2.1.

14.2.6 The generator prime movers are to be surveyed as required by Pt 1, Ch 3, 12 Turbines and steam engines - Detailed requirements and Pt 1, Ch 3, 13 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 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.

14.2.7 Where transformers 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 testing 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.

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

14.2.9 The emergency sources of electrical power, their automatic arrangements and associated circuits are to be tested.

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

14.2.11 Where the ship 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 cast resin 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 practicable. Insulating oil, if used, is to be tested in accordance with Pt 1, Ch 3, 14.2 Complete Surveys 14.2.7. 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.

14.2.12 Where the ship has high voltage electrical equipment and associated cables used for essential services, the Surveyor is to visually examine the condition of their insulation systems for signs of deterioration, including partial discharge activity. Where deemed necessary by the Surveyor, boroscopic and/or endoscopic inspections are to be conducted. Areas to be considered for examination are to include, but are not limited to:

• winding ends of all high voltage electrical machines;
• electrical motor core laminations; stator wedges; stator bars; space blocks; and connection rings;
• terminal connections of high voltage equipment; and
• high voltage cable connections.

14.2.13 Where on-line partial discharge monitoring equipment has been fitted to high voltage equipment used for the provision of essential services, the Surveyor is to review the test reports for signs of deteriorating performance of the insulation system, see Pt 6, Ch 2, 21.4 On-line partial discharge testing of high voltage rotating machines for essential services.

14.2.14 A General Examination of the electrical equipment in areas which may contain flammable gas or vapour and/or combustible dust is to be made to ensure that the integrity of the safe-type electrical equipment has not been impaired owing to corrosion, missing bolts, etc. and that there is not an excessive build-up of dust on or in dust protected electrical equipment. Cable runs are to be examined for sheath and armouring defects, where practicable, and to ensure that the means of supporting the cables are in good order. Tests are to be carried out to demonstrate the effectiveness of bonding straps for the control of static electricity. Alarms and interlocks associated with pressurized equipment or spaces are to be tested for correct operation.

14.2.15 For ships having an OPS notation assigned, the onshore power supply arrangements are to be examined and functionally tested whilst connected to an external electrical power supply in accordance with approved test schedules (see Pt 7, Ch 13 On-shore Power Supplies) during the Complete Surveys of machinery or, where it is not practical to provide the facilities and operations for testing during the required Surveys of other machinery items, within 12 months of the due date of the Complete Surveys of machinery.

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

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

14.2.18 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.

14.2.19 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.

14.3.1 For tankers five years old and over, Pt 1, Ch 3, 14.2 Complete Surveys 14.2.14 is to be complied with. In addition, an electrical insulation resistance test of the circuits terminating in, or passing through, the hazardous zones and spaces is to be carried out.