Insulation Resistance Test Procedure Of Current Transformer

Transformer winding resistance measurement is carried out to calculate the i 2 r losses and to calculate winding temperature at the end of a temperature rise test.

Insulation resistance test procedure of current transformer. The test is performed with a power factor test kit and the connections are the same as for the megger test the insulation resistance test. Isolation required for the test. Use caution when testing. Required equipment for testing.

Verify nameplate ratings are in accordance with the approved drawings and. Adjust megger tester at 1000 v dc. Insulation resistance decreases in temperature or moisture. It is also done at site to ensure healthiness of a transformer that is to check loose connections broken strands of conductor high contact resistance in tap changers high.

Use the megger test at a low voltage side. Before conducting a transformer winding resistance test it is important to observe all safety warnings and take proper precautions ensure that all equipment to be tested is properly grounded and treat all high voltage power equipment as energized until proven otherwise by using the proper lockout tagout procedures. Steps of this test. Mechanical check and visual inspection.

Insulation resistance is the ratio of the applied voltage dc to the total leakage current. It is carried out as a type test as well as routine test. Measure insulation resistance between low voltage windings and the main body of the transformer. Clean the terminals of the transformer.

Insulation resistance test of transformer is divided into three parts. Variac step up transformer 0 2kv primary current injection set. The insulation resistance test is of value for future comparison and also for determining if the transformer is to be subjected to the applied voltage test the winding insulation resistance test is a dc high voltage test used to determine the dryness of winding insulation system the test measures the insulation resistance from individual windings to. With a little record keeping and common sense however you can get a good picture of the insulation condition from values that are only relative.

This test can be repeated during the service life of the transformer and verified against the result obtained during manufacturing as a check to determine if the insulation is malfunctioning or decaying. Go to content 3.