The plate on the outside of the motor describing the motor, HP, voltage, RPM’s, efficiency, design, enclosure, etc.
NAVY SERVICE “A”
Motors designed to meet requirements of MIL M-17059 or MlL M-17060 for high shock and service and are essential to the combat effectiveness of a ship. These motors are usually made of nodular iron.
N.E.C. TEMPERATURE CODE (‘T’ CODE)
An index for describing maximum allowable “skin” (surface) temperature of a motor under any normal or abnormal operating conditions. The “T” codes are applicable to U.L. Listed explosion-proof motors. The skin temperature shall not exceed the minimum ignition temperature of the substances to be found in a hazardous location. The “T” code designations apply to motors and other types of electrical equipment subject to hazardous location classification.
SKIN TEMPERATURE IDENTIFICATION NUMBERS
|Maximum Surface||Degrees F||T-Codes ID|
for Class & Group
|280||536||T2A||Class I Group D w/Cautionary Label|
|215||419||T2D||Class I Group D|
|200||392||T3||Class ll Group E & F|
|180||356||T3A||Class I Group C w/Cautionary Label|
|165||329||T3B||Class ll Group G|
|160||320||T3C||Class I Group C|
The National Electrical Manufacturers Association (http://www.nema.org) is a non-profit organization organized and supported by manufacturers of electric equipment and supplies. NEMA has set standards on:
- H.P. ratings
- frame sizes and dimensions
- standard voltages and frequencies with allowable variations
- service factors
- starting current & KVA
NODULAR IRON (DUCTILE IRON)
Special cast iron with a crystalline formation which makes it capable of handling high shock.