Ground Fault Monitor

[Al Pike]

Do I need a ground fault monitor for a 3ph 200a 480v delta service? I recall someone telling me that the first short to ground creates a neutral and it takes the second short to trip OCPD. I've read 230.95 but I don't see my situation.

Thanks for the help

 

[StephenSDH]

If you have a new installation of an ungrounded service then yes 250.21(B). I assume yours would be grandfathered, but it is a very good idea to have the monitoring if you really have an ungrounded system.

 

[jim dungar]

Do I need a ground fault monitor for a 3ph 200a 480v delta service? I recall someone telling me that the first short to ground creates a neutral and it takes the second short to trip OCPD. I've read 230.95 but I don't see my situation.

Thanks for the help

Not quite.

The first fault creates a grounded conductor not a neutral.
Since the 2008 code you have been required to supply a monitor for ungrounded services.

 

[Al Pike]

Thanks Jim/Stephen. My inspector said it did not. Its for a storm Water pump station.Does 250.21B apply?

 

[raider1]

Thanks Jim/Stephen. My inspector said it did not. Its for a storm Water pump station.Does 250.21B apply?

For a new service I would say yes it would apply.

Chris