ROSSLYN, Va. - The National Electrical Manufacturers Association (NEMA) has publishedNEMA Application Guide for AC Adjustable Speed Drive Systems, which was produced by the 1IS Industrial Automation Control Products and Systems Section, SC7 Subcommittee on Adjustable Speed Drives.

“This document is intended to facilitate the design, selection of components, and installation of AC electrical drive systems, particularly where an induction motor is used in conjunction with an adjustable speed drive,” said James E. Armes, section chairman.

According to Armes, this revision includes updated terminology and information on motor terminal voltage transients, fundamental contributors to peak voltages, and single phase input for three-phase drives, as well as modification of the information on overload capability for motor selection. It also incorporates replacement of the term “cable corona inception voltage (CIV)” by “partial discharge inception voltage (PDIV).”

An electronic copy ofNEMA Application Guide for AC Adjustable Speed Drive Systemsmay be downloaded at no charge, or a hardcopy purchased for $101, by visiting NEMA’s Website at

Publication date:01/07/2008