16 General Provisions
16.1 The requirements for the design, construction, installation and operation of electrical equipment and systems including power sources, lighting, motors, miscellaneous equipment and safety systems shall be in accordance with accepted standards or to the satisfaction of the Administration.
16.2 Electrical equipment on a vessel shall be installed and maintained to—
.1 provide services necessary for safety under normal and emergency conditions;
.2 protect passengers, crew, other persons, and the vessel from electrical hazards, including fire, caused by or originating in electrical equipment, and electrical shock;
.3 minimize accidental personnel contact with energized parts; and
.4 prevent electrical ignition of flammable vapors.
16.3 Electrical equipment used in the following locations shall be drip-proof—
.1 a machinery space;
.2 a location normally exposed to splashing, water washdown, or other wet conditions within a galley, a laundry, or a public washroom or toilet room that has a bath or shower; or
.3 another space with a similar moisture level.
16.4 Electrical equipment exposed to the weather shall be watertight.
16.5 Electrical equipment exposed to corrosive environments shall be demonstrated to be of suitable construction and corrosion-resistant.
16.6 Electrical equipment and installation shall be designed and installed so that it is not affected by vessel motions or vibration of the vessel underway.
16.7 All equipment, including switches, fuses, lampholders, etc., shall be rated for the voltage and current utilized.
16.8 Receptacle outlets of the type providing a grounded pole or a specific direct current polarity shall be of a configuration that will not permit improper connection.
16.9 All electrical equipment and circuits shall be clearly marked and identified.
16.10 Any cabinet, panel, box or other enclosure containing more than one source of power shall be fitted with a sign warning persons of this condition and identifying the individual circuits.
17 Power Sources
17.1 Each vessel that relies on electricity to power the following loads shall be arranged so that the loads can be energized from two sources of electricity—
.1 fuel system;
.2 fire main;
.3 fixed fire fighting systems;
.4 bilge system;
.5 steering system;
.6 propulsion system and its necessary auxiliaries and controls;
.7 vessel's service and emergency electrical generation system and its necessary auxiliaries;
.8 a system identified by the Administration as being crucial to the survival of the vessel or to the protection of the personnel on board;
.9 interior lighting except for decorative lights;
.10 communication systems including a public address system required under regulation VII/6;
.11 navigation equipment and lights; and
.12 illumination of the survival craft launching and embarkation areas and man overboard rescue equipment and rescue areas.
17.2 A vessel with batteries of adequate capacity to supply the loads specified in IV/17.1 for three hours, or a generator or alternator driven by a propulsion engine, complies with the requirement of IV/17.1.
17.3 Where a vessel service generator driven by a propulsion engine is used as a source of electrical power, a vessel speed change, throttle movement or change in direction of the propeller shaft rotation shall not interrupt power to any of the loads specified in IV/17.1.
17.4 Each generator and motor shall be—
.1 in a location that is accessible, adequately ventilated, and as dry as practicable; and
.2 mounted above the bilges to avoid damage by splash and to avoid contact with low lying vapors.
17.5 A voltmeter and an ammeter shall be provided for a generator rated at 50 volts or more. For each alternating current generator, a means for measuring frequency shall also be provided.
17.6 Each generator shall be protected by an overcurrent device with set value not exceeding 115% of the generator full load rating.
17.7 A dual voltage generator installed on a vessel shall be of the grounded type, where—
.1 the neutral of a dual voltage system shall be solidly connected at the switchboard's neutral bus; and
.2 the neutral bus shall be connected to ground.
18 Electrical Systems
18.1 Electrical systems shall be two wire.
18.2 A system in which there is no intentional connection of the circuit to earth (an insulated system) shall be provided with double pole switches, except that single pole switches may be used in the final sub-circuit.
18.3 Single pole switches are accepted in a system with one pole earthed. Fuses shall not be installed in an earthed conductor.
18.4 The insulation resistance, using a low voltage instrument so as not to cause damage, shall not be less than 0.3 megohm for all new vessels, but a minimum of 0.1 megohm can be accepted on existing vessels.
18.5 All circuits, except the main supply from the battery to the starter motor and electrically driven steering motors, shall be provided with electrical protection against overload and short circuit, i.e. fuses or circuit breakers shall be installed. Short circuit protection shall be for more than twice the total rated current of the loads in the circuit protected.
18.6 Steering motors shall have an overload alarm in lieu of overload protection.
19 Cables and Wiring
19.1 Electrical cables shall be constructed and fitted to a recognised standard for marine use.
19.2 Cables which are not provided with electrical protection shall be kept as short as possible and shall be “short circuit proofed” e.g. single core with additional insulated sleeve over the insulation of each core. Single core marine cable, which has conductor insulation and a sheath will meet this requirement without an additional sleeve.
19.3 All wiring shall be carried out with flame retardant cable. When selecting cables for relevant applications, particular attention shall be given to environmental factors such as temperature and contact with damaging substances e.g. oils and chemicals.
19.4 Adequate provision shall be made for securing electrical connections, e.g. by use of locking washers.
19.5 Electrical cables shall be installed with due regard to minimizing physical damage and the effect of moisture.
20 Batteries
20.1 Where provisions are made for charging batteries, there shall be natural or induced ventilation sufficient to dissipate the gases generated.
20.2 Each battery shall be located as high above the bilge as practicable, secured to protect against shifting with the roll and pitch of the vessel, and free from exposure to water splash or spray.
20.3 Connections shall be made to battery terminals with permanent type connectors. Spring clips or other temporary clamps are prohibited.
20.4 A battery cut-out switch which acts as an isolator shall be provided for all systems. Where a battery change-over switch is fitted and is provided with an “off” position, this may serve as the cut-out switch also.
20.5 Batteries shall be mounted in trays lined with, or constructed of, a material that is resistant to damage by the electrolyte.
20.6 Battery chargers shall have an ammeter connected in the charging circuit.
20.7 Batteries used for engine starting shall be located as close as possible to the engine or engines served.
21 Battery InstalLation
21.1 Each battery installation connected to a battery charger having an output of more than 2kW, shall be located in a locker, room or enclosed box solely dedicated to the storage of batteries with adequate ventilation.
21.2 Each battery installation connected to a battery charger having an output of 2kW or less, shall be located in a well ventilated space and protected from falling objects and shall not be in a closet, storeroom or similar space.
22 General grounding requirements
22.1 A vessel's hull shall not carry current as a conductor except for the following systems—
.1 impressed current cathodic protection systems; or
.2 battery systems for engine starting.
22.2 Receptacle outlets and attachment plugs for portable lamps, tools, and similar apparatus operating at 100 volts or more, shall have a grounding pole and a grounding conductor in the portable cord.
22.3 Each nonmetallic mast and top mast shall have a lighting ground conductor.
23 Lighting
23.1 A single hazardous event shall not be capable of disabling all lighting systems.
23.2 Lighting circuits shall be distributed through the spaces so that a total blackout cannot occur due to the failure of a single protective device.
23.3 Where general lighting is provided by a single centralised source, an alternative source of lighting shall also be provided sufficient to enable persons to make their way to the open deck or to permit work on essential machinery.
24 Hazardous Spaces
24.1 Where practicable, electrical equipment shall not be installed in a space where petroleum vapour or other hydrocarbon gas may accumulate. When equipment is installed in such a space it shall comply with a recognised standard for prevention of ignition of flammable atmosphere.
24.2 Any compartment which contains a gas consuming appliance or any compartment into which flammable gas may leak or accumulate, shall be provided with a hydrocarbon gas detector and alarm. The detector and alarm shall be designed to comply with a recognised standard for prevention of ignition of flammable atmosphere.