Motor Marking

[tgifredday]

The NEC requires that equipment have markings that specify the temperature class or operating temperature at a 40 deg C ambient temperature, or at the higher designed ambient temperature. Are motors considered equipment in the NEC? Motors are not called out in the definition of equipment, but it could be considered equipment based on the definition. The motor section in NEC 501.125 does not call out a marking requirement, but does require the consideration of the temperature of internal and external surfaces that may be exposed to the flammable atmosphere.

 

[weressl]

The NEC requires that equipment have markings that specify the temperature class or operating temperature at a 40 deg C ambient temperature, or at the higher designed ambient temperature. Are motors considered equipment in the NEC? Motors are not called out in the definition of equipment, but it could be considered equipment based on the definition. The motor section in NEC 501.125 does not call out a marking requirement, but does require the consideration of the temperature of internal and external surfaces that may be exposed to the flammable atmosphere.

Some manufacturers do supply maximum surface temperatures under normal operating conditions for users to be able to determine suitability for Division 2 locations. In some cases it is stamped on the nameplate. AFAIK it is not part of the listing of the motor, but a volunteered information.