Instrument transformers find widespread use on high-voltage power systems for voltage and current indication involving metering and relaying, with testing routinely being performed on this equipment. In the case of capacitive coupling voltage transformers (CCVT) Doble tests are ideally suited to check the insulating qualities and functional characteristics of their paper/film/synthetic fluid coupling capacitors. In this webinar we will first review troubleshooting steps to take when the test results are unusual, and then present several case studies to illustrate how the root cause of unusual test results were determined.
