Comprehensive low-voltage motor specifications

This paper describes the circumstances and reasoning leading to the development of a comprehensive specification for low-voltage motors through NEMA frame size 447 (250 HP). The paper includes a brief explanation of an overall approach to the creation, management, and use of a guide specification database using extensive imbedded notes to the specifier. The paper also summarizes a practical approach for specifying and applying these motors with variable frequency drives, including their application in hazardous locations. Enclosures, bearings, speed, efficiency, vibration, insulation, housing construction, grounding, service factor, and warranty are all dealt with in a practical, comprehensive manner.<>