AC vs DC Hipot Test 2

[a10jp]

If I have a cable that is 375m long, and wish to do a hi-pot test, I would imagine a DC test is more suitable because AC test would induce abnormal capacitive current across the insulation, and result in a larger leakage current. Does everyine agree with this logic? Also, is there a standard what the DC hi-pot etst voltage should be? Is it alwasy SQRT(2) * AC Hipot etst voltage?

 

[cgrodzinski]

inclebob, every voltage AC, DC, VLF (technically it is AC) ... that is applied to the insulation will have some detrimental effect on it. If the voltage is high enough to break the insulation ... this is the outcome of the test.

The purpose of the "HI-POT" is to check if the cable insulation is capable of surviving the rated voltage. If it is not .... it MUST fail at any test.

The discussion still remains which of the test reveals cable weak points without killing a good one(to be simple).

Chris Grodzinski