N - Terms
NAMEPLATE
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. Iisted explosion-proof motors. The skin temperature shall not exceed the minimum ignition temperature of the substances to be found in the 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 Numbers | U/L Requirement for Class & Group |
|---|---|---|---|
| 450 | 842 | T1 | Not Available Reliance Product |
| 300 | 572 | T2 | Not Available Reliance Product |
| 280 | 536 | T2A | Class I Group D w/Cautionary Label |
| 260 | 500 | T2B | Not Available Reliance Product |
| 230 | 446 | T2C | Not Available Reliance Product |
| 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 |
| 135 | 275 | T4 | Not Available Reliance Product |
| 120 | 248 | T4A | Not Available Reliance Product |
| 100 | 212 | T5 | Not Available Reliance Product |
| 85 | 185 | T6 | Not Available Reliance Product |
NEMA
The National Electrical Manufacturers Association (https://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
- speeds
- frame sizes and dimensions
- standard voltages and frequencies with allowable variations
- service factors
- torques
- starting current & KVA
- enclosures
Reliance Electric is one of the founding members of NEMA.
NEMA I
See Weather protected machine, Type I
NEMA 11
See Weather protected machine, Type 11
NODULAR IRON (DUCTILE IRON)
Special cast iron with a crystalline formation which makes it capable of handling high shock.