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