Best Practices for clearing a ground on an ungrounded delta

[Shorted1]

Greetings
I am looking for an example document/policy related to best practices for clearing a ground on an ungrounded delta system. Maybe someone from an industrial location has one to share?

Thank You
Shorted1

 

[Zogzog]

I assume you have a ground detection system.

1. Turn off all loads (On that part of the system)
2. Have someone monitor the ground detector lights with a radio
3. restore loads 1 at a time, if ground shows up, turn that load off and continue restoring loads 1 at a time.

Or you can do it the way most industrial plants do, just wait for a 2nd ground and look for the smoke. (I am kidding, dont do this)

 

[Shorted1]

Thanks Zogzog
However, I am looking for a formal policy that someone may have in place at an industrial location. I am looking for an example that I can adjust for my facility.

Thanks
Shorted1

 

[waross]

You can build a "Thumper". Select a value of resistor that will allow a current of a few amps to flow at phase to phase voltage. Use a timer and relay (contactor) to cycle the resistor on and off once or twice a second. Connect this device between a good phase and the grounded phase. You should now be able to see this current on the grounded circuit conductor with an amprobe.
Beware of discontinuous (arcing) ground faults. Select the resistance/current in consultation with your plant electrical department.

Bill
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"Why not the best?"
Jimmy Carter

 

[burnt2x]

Try this: