A laboratory assessment of in-service and nonintrusive motor efficiency testing methods

Determining in-service motor efficiencies is important to industries concer ned with energy conservation and cost savings; however, nonintrusive effici ency measurements of installed motors can be difficult to obtain and even m ore difficult to verify. This paper describes an evaluation and comparison of 12 motor efficiency methods through laboratory testing to assess their a ccuracy and precision. Analysis of the methods and implementation procedure s is discussed, Additionally: four efficiency methods that are characterize d by a very low intrusion level are tested in further detail, and the resul ts of these tests are presented.