Insulation Resistance Test Of Transformer Pdf

Insulation resistance testing purpose.

Insulation resistance test of transformer pdf. September 5 7 2018 1. B kv is the rated machine terminal to terminal voltage. The test measures the insu lation resistance between the phases and or between phase and ground. 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.

It is commonly used in the industry for acceptance testing prior to energizing the cable and for maintenance testing programs. Measure insulation resistance between low voltage windings and the main body of the transformer. Insulation resistance testing is a non destructive test procedure. Excitation current test insulating fluid dielectric tests insulation pf test insulation resistance test ttr test.

Insulation resistance decreases in temperature or moisture. 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. Turns ratio test 8. Apply the test voltage and note the reading.

Adjust megger tester at 1000 v dc. The following tests are routinely conducted in the field on the 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. Clean the terminals of the transformer.

Overall power factor and capacitance 2. A rated line to line voltage for three phase ac machines line to ground voltage for single phase machines and rated direct voltage for dc machines or field windings. Insulation resistance test of transformer is divided into three parts. Voltage for transformer testing because ac voltage simulates the internal stress that the transformers face during operating conditions.

Megger insulation resistance test device. Value at 60 seconds after application of the test voltage is referred to as the insulation resistance of the transformer at the test temperature. Use the megger test at a low voltage side. Ansi neta mts 2015 table 100 11 insulation resistance test values rotating machinery for one minute at 40 c.

The transformer neutral bushing is to be disconnected from earth during the test. Time resistance testing method this method is fairly independent of temperature and often. Bushing power factor and capacitance. Steps of this test.

Values based on ieee std 43 2013.