A study of corona discharge and surface tracking in the intermediate voltage range 2 to 3 kVAC

Laboratory testing of motorette specimens showed that specimens failed in a matter of minutes when subjected to test voltages of 2300 VAC to 2500 VAC. A study was designed and implemented to determine the mode of failure and identify the cause. The author presents the steps taken, the information learned at each step, and the results of this evaluation. It was shown that the cause of failure was a combination of a corona-type discharge and the related surface tracking. A direct relationship was also found between specimen failure and moisture, physical design of the specimen, environment, and applied voltage.<>