[Code of Federal Regulations]

[Title 46, Volume 4]

[Revised as of October 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 46CFR111.01-15]



[Page 214]

 

                           TITLE 46--SHIPPING

 

   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)

 

PART 111_ELECTRIC SYSTEMS_GENERAL REQUIREMENTS--Table of Contents

 

                         Subpart 111.01_General

 

Sec. 111.01-15  Temperature ratings.



    (a) In this subchapter, an ambient temperature of 40[deg]C 

(104[deg]F) is assumed except as otherwise stated.

    (b) A 50[deg]C (122[deg]F) ambient temperature is assumed for all 

rotating electrical machinery in boiler rooms, engine rooms, auxiliary 

machinery rooms, and weather decks, unless it can be shown that a 

45[deg]C (113[deg]F) ambient temperature will not be exceeded in these 

spaces.

    (c) A 45[deg]C (113[deg]F) ambient temperature is assumed for cable 

and all other non-rotating electrical equipment in boiler rooms, in 

engine rooms, in auxiliary machinery rooms, and on weather decks. For 

installations using UL 489 SA marine type circuit breakers the ambient 

temperature for that component is assumed to be 40[deg]C (104[deg]F). 

For installations using Navy type circuit breakers the ambient 

temperature for that component is assumed to be 50[deg]C (122[deg]F).

    (d) Unless otherwise indicated in this subchapter, a 55[deg]C 

(131[deg]F) ambient temperature is assumed for all control and 

instrumentation equipment.

    (e) If electrical equipment is utilized in a space in which the 

equipment's rated ambient temperature is below the assumed ambient 

temperature of the space, its load must be derated. The assumed ambient 

temperature of the space plus the equipment's actual temperature rise at 

its derated load must not exceed the equipment's total rated temperature 

(equipment's rated ambient temperature plus its rated temperature rise).



[CGD 94-108, 61 FR 28276, June 4, 1996, as amended at 62 FR 23907, May 

1, 1997; USCG-2004-18884, 69 FR 58348, Sept. 30, 2004]