[Title 46 CFR 111.54]
[Code of Federal Regulations (annual edition) - October 1, 1996 Edition]
[Title 46 - SHIPPING]
[Chapter I - COAST GUARD, DEPARTMENT OF]
[Subchapter J - ELECTRICAL ENGINEERING]
[Part 111 - ELECTRIC SYSTEMS--GENERAL REQUIREMENTS]
[Subpart 111.54 - Circuit Breakers]
[From the U.S. Government Publishing Office]




  46
  SHIPPING
  4
  1996-10-01
  1996-10-01
  false
  
  111.54
  Subpart 111.54
  
    SHIPPING
    COAST GUARD, DEPARTMENT OF
    ELECTRICAL ENGINEERING
    ELECTRIC SYSTEMS--GENERAL REQUIREMENTS
  


                    Subpart 111.54--Circuit Breakers



Sec. 111.54-1  Circuit breakers.

    (a) Each Circuit breaker must--
    (1) Meet the general provision of article 240 of the NEC or IEC 92-
202, as appropriate;
    (2) Meet subpart 111.55 of this part; and
    (3) Have an interrupting rating sufficient to interrupt the maximum 
asymmetrical short-circuit current available at the point of 
application.

[[Page 239]]

    (b) Molded case circuit breakers must not be used in circuits having 
a nominal voltage of more than 600 volts (1,000 volts for circuits 
containing circuit breakers manufactured to IEC requirements). Each 
molded case circuit breaker must meet UL 489 and its marine supplement 
489 SA or IEC 947-2 Part 2, except as noted in paragraph (e) of this 
section.
    (c) Circuit breakers, other than the molded case type, that are for 
use in one of the following systems must meet the following 
requirements:
    (1) An alternating current system having a nominal voltage of 600 
volts or less, or 1,000 volts for IEC standard circuit breakers must 
meet--
    (i) IEEE C37.13;
    (ii) IEEE Std 331; or
    (iii) IEC 947-2, Part 2.
    (2) A direct current system of 3,000 volts or less must meet ANSI 
C37.14 or IEC 947-2, Part 2.
    (3) An alternating current system having a nominal voltage greater 
than 600 volts, or greater than 1,000 volts for IEC standard circuit 
breakers must meet--
    (i) ANSI/IEEE C37.04 including all referenced supplements, IEEE Std 
320 including all referenced supplements, and ANSI C37.12; or
    (ii) IEC 947-2, Part 2.
    (d) A circuit breaker must not:
    (1) Be dependent upon mechanical cooling to operate within its 
rating; or
    (2) Have a long-time-delay trip element set above the continuous 
current rating of the trip element or of the circuit breaker frame.
    (e) Each circuit breaker located in an engineroom, boilerroom, or 
machinery space must be calibrated for a 50 degree C ambient 
temperature. If the circuit breaker is located in an environmentally 
controlled machinery control room where provisions are made for ensuring 
an ambient temperature of 40 degree C or less, a circuit breaker must 
have at least the standard 40 degrees C ambient temperature calibration.

[CGD 74-125A, 47 FR 15236, Apr. 8, 1982, as amended by CGD 94-108, 61 FR 
28279, June 4, 1996; 61 FR 33045, June 26, 1996]



Sec. 111.54-3  Remote control.

    Remotely controlled circuit breakers must have local manual means of 
operation.

[CGD 81-030, 53 FR 17847, May 18, 1988]