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-25 -25 Alternating-current ship's service switchboards

The exact 46 CFR §111.30-25 text, rendered cleanly with its subsection structure — plus how this rule shows up on the exam.

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TL;DR

(a) Except as allowed in paragraph (g) of this section, each alternating-current ship's service switchboard must have the equipment required by paragraphs (b) through (f) of this section.

Section 111.30-25 — full text

Rendered cleanly from the source — the exact regulatory text, with subsection structure preserved.

(a)Except as allowed in paragraph (g) of this section, each alternating-current ship's service switchboard must have the equipment required by paragraphs (b) through (f) of this section.

(b)For each connected generator, each switchboard must have the following:

(1)A circuit breaker that meets § 111.12-11 and § 111.50-5.

(2)A disconnect switch or link for each generator conductor, except a switchboard having a draw-out or plug-in type generator circuit breaker that disconnects:

(i)Each generator conductor; or

(ii)If there is a switch in the generator neutral, each ungrounded conductor.

(3)An indicator light connected between the generator and the circuit breaker.

(4)An ammeter with a selector switch that connects the ammeter to show the current in each phase.

(5)A voltmeter with a selector switch that connects the voltmeter to show the:

(i)Generator voltage of each phase; and

(ii)Bus voltage of one phase.

(6)A voltage regulator and voltage regulator functional cut-out switch.

(c)For each generator that is not excited from a variable voltage or rotary amplifier that is controlled by a voltage regulator unit acting on the exciter field, each switchboard must have:

(1)A generator field rheostat;

(2)A double-pole field switch;

(3)Discharge clips; and

(4)A discharge resistor.

(d)If generators are arranged for parallel operation, each switchboard must have:

(1)A speed control for the prime mover of each generator;

(2)A wattmeter for each generator; and

(3)A synchroscope and synchronizing lamp that have a selector switch to show synchronization for paralleling generators.

(e)Each switchboard must have the following:

(1)Ground detection that meets subpart 111.05 for the:

(i)Ship's service power system;

(ii)Normal lighting system; and

(iii)Emergency lighting system.

(2)A frequency meter with a selector switch to connect the meter to each generator.

(3)An exciter field rheostat.

(f)For each shore power connection each switchboard must have:

(1)A circuit breaker or fused switch;

(2)An indicator connected to the shore side of the circuit breaker or fused switch; and

(3)One of the voltmeters under paragraph (b)(5) of this section connected to show the voltage of each phase of the shore power connection.

(g)The equipment under paragraphs (b)(1) and (2) and (f)(1) of this section, except the equipment under paragraphs (b)(1) and (2) and (f)(1) of this section, must be on the ship's service switchboard or on a central control console that:

(1)Is in the same control area as the main ship's service switchboard or can remotely control the ship's service generator circuit breaker;

(2)Has a generator section that has only generator functions;

(3)Has the generator section segregated from each other console section by a fire-resistant barrier; and

(4)Has cabling from the main switchboard to the generator section of the console that:

(i)Has only generator control and generator instrumentation circuits; and

(ii)Is protected from mechanical damage. [CGD 74-125A, 47 FR 15236, Apr. 8, 1982, as amended by USCG-2020-0075, 88 FR 16361, Mar. 16, 2023]

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46 CFR §111.30-25 — -25 -25 Alternating-current ship's service switchboards · CaptainsGround