Service Entrance 6 Disconnect Rule Ground Fault Protection

[mull982]

I am not sure about that. You have CTs on the secondary that are connected to a protective relay that trips the primary. That can be set up to provide the protection that is required by 240.21(C) as well as the GFP required by 215.10.

This is what I was thinking but wanted to be sure

 

[augie47]

I am not sure about that. You have CTs on the secondary that are connected to a protective relay that trips the primary. That can be set up to provide the protection that is required by 240.21(C) as well as the GFP required by 215.10.

I agree that the CT would offer protection. When I posted I had forgotten about 240.90 and I would imagine this install would fit that bill. I don't see that very often.

 

[Smart $]

I am not sure about that. You have CTs on the secondary that are connected to a protective relay that trips the primary. That can be set up to provide the protection that is required by 240.21(C) as well as the GFP required by 215.10.

This is what I was thinking but wanted to be sure

I agree that the CT would offer protection. When I posted I had forgotten about 240.90 and I would imagine this install would fit that bill. I don't see that very often.

I agree. Guess I wasn't thinking... I was in a rush to get out the door when I posted.

 

[Haji]

I've attached a One-Line that will hopefully clear up some of the confusion.

All equipment will be owned by customer.

From the one line diagram it is seen that, beyond metering point till the (over head) lines terminate on primary breaker, no protection is shown to be provided to the lines or to the tap, even though the lines belong to the customer and in case of fault in them, the fault may have to burn free to clear. So keep fire fighting equipment ready.

 

[don_resqcapt19]

From the one line diagram it is seen that, beyond metering point till the (over head) lines terminate on primary breaker, no protection is shown to be provided to the lines or to the tap, even though the lines belong to the customer and in case of fault in them, the fault may have to burn free to clear. So keep fire fighting equipment ready.

That is typical for all services. Between the service point and the service OCPD, there is no short circuit or ground fault protection for those conductors. The service OCPD provides overload protection for those conductors, but not short circuit or ground fault protection.

 

[Haji]

That is typical for all services.

May be so in US. May not be so in other countries like India: to reduce fire risk, fuse and disconnect are provided as near service meter point as possible.