Answer / naresh chandra jha

Hi-pot test is used to check the leakage current of HT
breaker , Ht bus bar,HT cable .In this test (3v+1)80%
voltage is applied in one phase and leakage current is
measure in other two phase(which is shorted )with the help
of multimeter ,which is connected in hipot kit .In hipot
test ,voltage is step up with the help of auto
transformer(variac) and hipot kit. this hi voltage(AC
voltage for breaker ,bus bar and DC voltage for cable )is
applied in phase. DC voltage is created with the help of
diode which is connected in series with AC voltage(hipot kit) .

Answer / shao

Thank you so much Naresh!

But i think we only measure the respective leakage current at that phase on which we have applied voltage.?
e-g; Applied 40KV at Red phase for 60sec, & measured leakage current was 0.6micro Amperes.

Actually im seeing this testing at a 132KV Grid Station.

can we use ordinary transformer in place of autotransformer?give reasons also

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