High Resistance Grounding (HRG) Capacitive Charging Current Test

Electrical Testing Talk
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I need to perform a capacitive charging current test on a new HRG at 480V. The customer specification says, “The neutral conductor shall be disconnect from the transformer and a single line-to-ground fault place on the system under test. The resulting ground fault current shall be measured and recorded.”

To be honest, this seems really dangerous. My initial thought would be to run a cable from the load side of small molded case breaker or fused disconnect switch to the ground bar, and measure the current when the breaker or switch is closed, but I really wouldn’t want to be the one who has to close the breaker or switch.

I’ve been searching google for a test kit that would allow this test to be performed while standing outside of the arc flash boundary, but I can’t find anything.

Does anybody have a lead on a test kit designed for this? Do I need to build one with a small contactor integrated into a pelican case and a long cord, where I can push a button to close the contactor from 20 feet away?

Appreciate any feedback or advice you can give.

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Megger MS-2 single phase current injection test set should do it. It can output nearly 200A from a standard 15A receptacle, it has a variable dial and timing contacts. If you can get the impedance right down it can output much higher, but duty cycles are signifcantly reduced. 30 secs on to 5 mins off for 200A, I’ve gotten my set up to around 600A momentarily. Please don’t use the breaker, thats asking for trouble, injury, and damaged equipment.

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