how to perform insulation resistance test on three phase transformer

[mask12900]

please describe step by step guide how to perform insulation resistance test on three phase 2000 kva transformer

[Kerry4407]

please describe step by step guide how to perform insulation resistance test on three phase 2000 kva transformer

The answer to your question can be as lengthy as you would like, but the essentials are that there are 3 tests to perform:. Primary to Secondary with the ground guarded, primary to ground with the secondary guarded and secondary to ground with the primary guarded. The use of the guard will apply if the transformer in question is a Delta-Wye, Wye-Delta or a Delta-Delta. The guard cannot be used with a Wye-Wye where the H0 and X0 are tied together. Tests are conducted at voltages that exceed the Insulation rating but not the manufacturers recommended maximum. Tests are typically held for 10 minutes with readings recorded every minute in order to calculate a polarization index.