Insulation Resistance Test on a Transformer

Class 1 Transformer

Insulation resistance tests between each winding and earth

Insulation resistance test between windings

The minimum insulation resistance value accepted in each of the above tests is 2M. A 500V Insulation Resistance Test is suitable for 110 – 400 Volt transformers.

Class 2 Transformer

Double Insulated Symbol

Insulation Resistance Test Between Windings

The minimum insulation resistance value accepted in the test is 2 M.