we have taken HV test of 2.5 k and Megger test on 11 kv HT
cable.here it shows no fault but when we are charging the
same cable with 11 kv supply why the VCB 11 kv gets tripped
can anybody define the possible cause of fault ?
Answer Posted / shariff
The 11kV cable will be designed for morethan 12kV and the
megger applied voltage is just 20% of that rating.. so the
cable insulation might be withstanding at that vg but it is
failing at higher voltage.. So go for the Hi pot test with
DC pulse nearly 15kV...
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