Experience with dielectric diagnosis of high voltage motors in service

Abstract

Field testing and extensive laboratory investigations indicate that periodic diagnostic tests such as tan delta, capacitance, and IDE (integrated discharge energy) give useful information on the relative condition of winding insulation. Each test parameter provides particular information regarding the condition of stator insulation should be monitored and as many diagnostic parameters as possible should be monitored to obtain reliable and complete information regarding the state, quality, and trend in ageing of the insulation. A strong correlation has been shown to exist between tan delta and capacitance tip-ups.<>