Carried out dc dielectric test for a 33KV XLPE cable at 54kvdc recently. The cable has not been energized. However, the client wants to retest the cable. What should be the test voltage? Remain the same at 54kvdc or lower? Any suggestions or is there any standard to follow?
With regards to the insulation improvement, Could it be there were moisture present in the air gap of the cable and the moisture was removed during hipot test and that led to an improvement of the insulation level?
With regards to the insulation improvement, Could it be there were moisture present in the air gap of the cable and the moisture was removed during hipot test and that led to an improvement of the insulation level?
Thanks for all the replies.
Are there any chances that the insulation level will improve after dc hipot test cable? Meggar reading before hipot is 10Gohms. Meggar reading after hipot test is 100Gohms. What is the reason behind this insulation improvement?