Before the switchgear can be energized and put into operation, a power frequency AC high voltage test is carried out to verify that the dielectric strength of its components, the insulating medium and all other parts are sound and within their required limits so that the switchgear can operate safely on the system voltage without breakdown.
The test is carried out using a separate source AC high voltage test set to generate the required test voltage into the switchgear. The test set is also capable of passing the leakage current at the test voltage.
