General Requirements for Ships of Groups 1 to 5B

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1.1 Electrical installations in ships of Group 1 to 5B shall be such that:

1. all auxiliary services necessary for maintaining the ship in normal operational and habitable conditions will be assured without recourse to the emergency source of power,
2. services essential for safety will be assured under various emergency conditions; and
3. the safety of passengers, crew and ship from electrical hazards will be assured.

1.2

1. every ship, the electrical power of which constitutes the only means of maintaining auxiliary services indispensable for the propulsion and safety of the ship, shall be provided with a main source of power which shall include at least two generating sets;
2. the power of these sets shall be such that it shall still be possible to ensure the functioning of the services referred to in paragraph 1.1 (a) in the event of any one of these generating sets being stopped;
3. the arrangements of the ship's main source of power shall be such that the services referred to in paragraph 1.1 (a) can be maintained regardless of the speed and direction of the main propelling engines or shafting;
4. in addition, the generating plant shall be such as to ensure that with any one generator or its primary source of power out of operation, the remaining generator(s) will be capable of providing the electrical services necessary to start the main propulsion plant form a dead ship condition; the emergency generator may be used for the purpose of starting from a dead ship condition if its capability either alone or combined with that of any other generator is sufficient to provide at the same time those services required in an emergency; and
5. where transformers constitute an essential part of the supply system required by this paragraph, the system shall be so arranged as to ensure the same continuity of the supply, as stated in this paragraph.

1.3

1. a main electric lighting system which shall provide illumination throughout those parts of the ship normally accessible to and used by the passengers or by the crew shall be supplied from the main source of power;
2. the arrangement of the main lighting system shall be such that a fire or other casualty in the space(s) containing the main source of power, including transformers, if any, shall not render the emergency lighting system inoperative;
3. the arrangement of the emergency lighting system shall be such that a fire or other casualty in the space(s) containing the emergency source of power, including transformers, if any, shall not render the main lighting system required by this Standard inoperative; and
4. all emergency lights shall be marked with a red letter “E” at least 13 mm high.

1.4 The main switchboard shall be so placed relative to one main generating station that, as far as is practicable, the integrity of the normal supply may be affected only by a fire or other casualty in one space; an environmental enclosure for the main switchboard, such as may be provided by a machinery control room situated within the main boundaries of the space, is not to be considered as separating the switchboard from the generators.

1.5 In every ship where the total installed electrical power of the main generators is in excess of 3 megawatts, the main bus bars shall be subdivided into at least two parts which shall normally be connected by removable links or equivalent arrangements; so far as is practicable, the connection of generators and any other duplicated equipment shall be equally divided between the parts; equivalent alternative arrangements shall be permitted.

1.6 Emergency generating sets shall be capable of being readily started in their cold condition; if this is impracticable, or if lower temperatures are likely to be encountered, provision shall be made for the maintenance of heating arrangements, to ensure ready starting of the generating sets.

1.7 Each emergency generating set that is arranged to be automatically started shall be equipped with starting devices with a storage energy capability of at least three consecutive starts; the source of stored energy shall be protected to preclude critical depletion by the automatic starting system, unless a second independent means of starting is provided; a second source of energy is to be provided for an additional three starts within 30 minutes unless hand (manual) starting can be demonstrated to be effective.

1.8 The stored energy shall be maintained at all times, as follows:

1. electrical and hydraulic starting systems shall be maintained from the emergency switchboard;
2. compressed air starting systems may be maintained by the main or auxiliary compressed air receivers through a suitable non-return valve or by an emergency air compressor which, if electrically driven, is supplied from the emergency switchboard; and
3. all of these starting, charging and energy storing devices shall be located in the emergency space; these devices are not to be used for any purpose other than the operation of the emergency generating set; this does not preclude the supply to the air receiver of the emergency generating set from the main or auxiliary compressed air system through the non-return valve fitted in the emergency generator space.

1.9 Where automatic starting is not required, manual starting is permissible, such as manual cranking, inertia starters manually charged hydraulic accumulators, or powder charge cartridges, where they can be demonstrated as being effective.

1.10 When manual starting is not practical, the requirements of subsections 1.7 and 1.8 shall be complied with except that starting may be manually initiated.

1.11 An indicator shall be provided in a suitable place on the main switchboard or in the machinery control room to indicate when the emergency generator is running.

1.12 Emergency generator/power equipment, control devices, and their associated wiring shall not be located in the same space as equipment and control devices which control, supply and distribute the main source of power unless the devices and equipment are arranged for “Fail Safe” operation; (i.e. failure of such equipment or devices would not affect the operation of the emergency power source).

1.13 Every passenger ship with open or enclosed ro-ro cargo spaces or special category spaces and which also has enclosed public areas shall be equipped with an supplementary emergency lighting in addition to the required emergency lighting; the supplementary emergency lighting shall be as follows:

1. all passenger public spaces and alleyways shall be provided with supplementary emergency lighting that can operate for at least three hours when all other sources of electric power have failed and under any condition of heel;
2. the source of power for the supplementary emergency lighting shall consist of accumulator batteries located within the lighting units that are continuously charged, where practicable, from the emergency switchboard; alternate means of lighting that are equally effective may be installed if plans of the lighting and its installation are submitted to the Board for inspection prior to installation; the supplementary emergency lighting shall be such that any failure of the lamp will be immediately apparent;
3. any accumulator battery provided shall be replaced at intervals having regard to the specified service life in the ambient conditions that they are subject to in service,
4. a portable rechargeable battery operated hand lamp shall be provided in every crew space alleyway, recreation space, and every working space which is normally occupied, unless supplementary emergency lighting, as required by 1.13 (a) and (b) is provided.

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