46 C.F.R. Subpart 111.20—Transformer Construction, Installation, and Protection
Title 46 - Shipping
Each transformer winding must be resistant to moisture, sea atmosphere, and oil vapor, unless special precautions are taken, such as enclosing the winding in an enclosure with a high degree of ingress protection. [CGD 94–108, 61 FR 28278, June 4, 1996] (a) The temperature rise, based on an ambient temperature of 40 degrees C, must not exceed the following: (1) For Class A insulation, 55 degrees C. (2) For Class B insulation, 80 degrees C. (3) For Class F insulation, 115 degrees C. (4) For Class H insulation, 150 degrees C. (b) If the ambient temperature is higher than 40 degrees C, the transformer must be derated so that the total temperature stated in this section is not exceeded. The temperature must be taken by the resistance method. An autotransformer must not supply feeders or branch circuits. Each transformer must have protection against overcurrent that meets article 450 of the NEC or IEC 92–303. [CGD 94–108, 61 FR 28278, June 4, 1996]
Title 46: Shipping
PART 111—ELECTRIC SYSTEMS—GENERAL REQUIREMENTS
Subpart 111.20—Transformer Construction, Installation, and Protection
§ 111.20-1 General requirements.
§ 111.20-5 Temperature rise.
§ 111.20-10 Autotransformers.
§ 111.20-15 Transformer overcurrent protection.
