Megger Testing

For testing a cable of 4.16 Kv & 13.8 KV what is the Value of Voltage at which it should be meggered? We had a testing company which was doing VLF testing, they tested both before & after the test Ir values. For 4.16 KV it was 5KV. I will have to check for 13.8 KV. Is there any standard related to it?


NETA Acceptance Testing Standard ATS 2007, Table 100.1 titled “Insulation Resistance Test Values for Electrical Apparatus and Systems” states that both 5kV and 15kV rated equipment is to be tested at 2500VDC when performing an insulation resistance test.

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