How to do P.I test in transformer.

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The P.I test in transformers is performed to determine the insulation condition and losses in the transformer.

P.I test stands for Polarization Index test.
It is a type of insulation resistance test.
The test measures the ratio of insulation resistance at 10 minutes to the insulation resistance at 1 minute.
The test helps in assessing the insulation condition and detecting any moisture or contamination in the transformer.
A high P.I value indicates good insulation, while a low value indicates poor insulation.
The test is conducted by applying a DC voltage to the transformer winding and measuring the insulation resistance.
The test voltage is typically 500V or 1000V.
The P.I test is performed at room temperature and repeated after heating the transformer.
The test results are compared with the manufacturer's specifications or industry standards to determine the insulation condition.

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