A motor primer. I

In recent years, much has been written about applying motors on variable speed drives, high speed rigid shaft motors, impact on API Standard 541, motor diagnostics, etc. Most of these papers and articles assume that the reader has significant knowledge of motor theory and operation. However, this assumption is overly optimistic, considering that few, if any colleges teach motor theory today and that application experience at motor user locations has been reduced in recent years. This paper is the first of a series of papers. The authors present motor theory and application information with an extensive reference list that will help engineers understand such questions as: What causes a motor to make noise?; Why is a medium voltage motor different than a low voltage motor?; and How should a motor be grounded? This paper will serve as a valuable reference for those who apply and specify motors