§ 28.370 - Wiring methods and materials.  


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  • § 28.370 Wiring methods and materials.

    (a) All cable and wire must have insulated, stranded copper conductors of the appropriate size and voltage rating for the circuit.

    (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting circuits must be No. 14 AWG or larger. Conductors must be sized so that the voltage drop at the load terminals is not more than 10 percent.

    (c) Cable and wiring not serving equipment in a high risk fire area such as a galley, laundry, or machinery space must be routed as far as practicable from these spaces. As far as practicable, cables serving duplicated essential equipment must be separated so that a casualty that affects one cable does not affect the other.

    (d) Cable and wire for power and lighting circuits must:

    (1) For circuits of less than 50 volts, meet 33 CFR 183.425 and 183.430; and

    (2) For circuits of 50 volts or greater:

    (i) Meet sections 310-13 and 310-15 of NFPA 70, except that asbestos insulated cable and dry location cable must not be used;

    (ii) Be listed by Underwriters Laboratories Inc. as UL Boat or UL Marine Shipboard cable; or

    (e) All metallic cable armor must be electrically continuous and grounded to the metal hull or the common ground point at each end of the cable run, except that final sub-circuits (those supplying loads) may be grounded at the supply end only.

    (f) A wiring termination and connection must be made in a fire retardant enclosure such as a junction box, fixture enclosure, or panel enclosure. A fire retardant plastic enclosure is acceptable.