---
kind: "section"
citation: "46 C.F.R. § 111.30-25"
title: "46"
number: "111.30-25"
heading: "Alternating-current ship's service switchboards."
url: "https://uscodex.org/cfr/46/111.30-25"
---

# §111.30-25. Alternating-current ship's service switchboards.

- (a) Except as allowed in [paragraph (g)](#g) of this section, each alternating-current ship's service switchboard must have the equipment required by [paragraphs (b) through (f)](#b..f) of this section.
- (b) For each connected generator, each switchboard must have the following:
  - (1) A circuit breaker that meets [§ 111.12-11](/cfr/46/111.12-11.md) and [§ 111.50-5](/cfr/46/111.50-5.md).
  - (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](/cfr/46/subpart111.05.md) 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)](#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)](#b-1) and [(2)](#b-2) and [(f)(1)](#f-1) of this section, except the equipment under paragraphs [(b)(1)](#b-1) and [(2)](#b-2) and [(f)(1)](#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.**

## Notes

### Amendments

[CGD 74-125A, 47 FR 15236, Apr. 8, 1982, as amended by USCG-2020-0075, 88 FR 16361, Mar. 16, 2023]

### Authority

Authority: 46 U.S.C. 3306, 3703; DHS Delegation No. 00170.1, Revision No. 01.2. Section 111.05-20 and Subpart 111.106 also issued under sec. 617, Pub. L. 111-281, 124 Stat. 2905.

### Source

Source: CGD 74-125A, 47 FR 15236, Apr. 8, 1982, unless otherwise noted.

### Amendments

[CGD 74-125A, 47 FR 15236, Apr. 8, 1982, as amended by USCG-2020-0075, 88 FR 16361, Mar. 16, 2023]