PSNet,
Here's a reference to an article that might be of interest... - - - - - IEEE Transactions on Dielectrics and Electrical Insulation Vol. 7 No. 6, December 2000 A Quantative Approach to Estimate the Life Expectancy of Motor Insulation Systems by Hashem Oraee Sharif University of Technology Iran ABSTRACT Electric motors represent the largest single load in most power systems. With continuing increase in nonlinear loads, the effects of harmonic contents of power systems on various components is becoming more important. This paper is concerned with the effect of power system harmonics and voltage unbalance on the useful life of electric motors. A simple equivalent circuit is used to calculate the additional heat losses caused by supply distortions. A lumped parameter thermal network is proposed to calculate the resulting heat distribution within the machine. An Arrhenius chart is then used to estimate motor insulation remaining life. The proposed approach is used to determine the effect of supply harmonics and voltage unbalance on the useful life of a three-phase induction motor and the results are verified experimentally. - - - - - As at other times, I am not a library nor can I provide copies. Get your copy from your local technical library. br, Pete Peter E Perkins, PE Principal Product Safety Consultant Tigard, ORe 97281-3427 503/452-1201 fone/fax p.perk...@ieee.org ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson: pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org