Insulation Resistance Test Using Megger Of Transformer

Power factor testing of power and distribution transformers the transformer is probably one of the most useful electrical devices ever invented.

Insulation resistance test using megger of transformer.

Since 80 of electrical maintenance and testing. Megger test equipment help to measure transformer insulation resistance winding resistance sweep frequency response analysis and oltc diagnosis tests enable the assessment and overall health of the transformer to be determined. Insulation resistance test of transformer is divided into three parts. As can be carried out by the megger transformer ohmmeter mto series of transformer test equipment then it s likely to.

The megger insulation tester is essentially a high range resistance meter ohmmeter with a built in direct current generator. The transformer neutral bushing is to be disconnected from earth during the test. Record the value of insulation resistance measured by megger tester after applying 1 min. Measure insulation resistance between low voltage windings and the main body of the transformer.

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. For good insulation the resistance usually reads in the megohm range. A failing transformer is a costly replacement in an electrical system with the potential for a long downtime.

This guide explains the many types of transformer and the power factor test procedures for each one. Apply the test voltage and note the reading. Megger s delta4000 automatically produces the itc for each transformer and provides confidence that the power factor tan δ result is accurately corrected to a 20 c equivalent value. The easy to use software interface powerdb minimizes time required to learn how to use the delta4000 and perform these tests correctly.

Hands down without a doubt one of the most universally searched topics on ec m s website from a historical perspective is insulation resistance testing as a result some of our most popular evergreen articles like understanding insulation resistance testing continue to top the charts when it comes to most popular content. Transformer insulation resistance deterioration is one of the most common causes of transformer failure. The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms.