IEEE 841-2009

This standard applies to premium-efficiency totally enclosed fan-cooled (TEFC), horizontal and vertical, single-speed, squirrel cage polyphase induction motors, up to and including 370 kW (500 hp), and 4000 V nominal, in National Electrical Manufacturers Association (NEMA) frame sizes 143T and larger, for petroleum, chemical, and other severe-duty applications (commonly referred to as premium-efficiency severe-duty motors). Excluded from the scope of this standard are motors with sleeve bearings and additional specific features required for explosion-proof motors.