@pillay said:
@doc70 said:
I have a 13800V to 600V 2MVA step-down transformer.I need to megger test this unit, I have a megger good for 5KV and also a hi-pot DC tester (Megger brand).
I am unclear of how to make the physical connections between the transformer and the testers.
make sure the transformer is not connected to any thing like the potential transformer,than carry out
[1] usual insulation test between the frame and the connections terminations of the ht side.
[2] test between frame and the lv side terminations.
[3] test between ht terminations and LV terminations.
[4] test between phases at HT side
[5] test between phases at LV side.
[6]
Dear Doc70 ;
Refer to Mr. Pillay said, I want to mentioned that the Insulation test Steps are mentioned by Mr. Pillay are 100% correct, but there’s 2 points :
– If the primary voltage is ” 13.8kV “, the ” Insulation voltage ” should be around ” 17.5kV ” ( depending on the manufactere information ), so, what are the obtaining results with ” 5kV ” ?
– If the secondary voltage is ” 600V “, the ” Insulation voltage ” should be around ” 800V ” ( depending on the manufactere information ), so, you can’t do the insulation test for the secondary with ” 5kV “.