Automated testing of high voltage insulation using a micro-processor controlled tangent delta bridge and power supply

Insulation measurements on high voltage equipment are usually performed using a bridge method, comparing the specimen against a known standard. The measuring process involves adjusting the high voltage level, reading a nullindicator, balancing the bridge, transcribing the readings and eventually analyzing the data. This process has been completely automated by means of a micro-processor and a measuring system suitable for high voltage laboratories or assembly line testing is described in this paper.