primary grounding on a separately derived system

[cheaptape]

I am sub feeding a 480v panel that is to feed a 480-208/120 transformer. my ? is do I tie my grounding conductor from my feed from my 480v panel in with the grounding conductor to my 208/120 panel together at the transformer of do I just bond it to the case of the transformer and keep it sep from my grounding conductor that feeds my 208/120 panel that is tied in with XO on the transformer and my building steel.

 

[infinity]

You can connect it directly to the case if you so choose.

 

[chris kennedy]

do I just bond it to the case of the transformer and keep it sep from my grounding conductor that feeds my 208/120 panel that is tied in with XO on the transformer and my building steel.

Your system bonding jumper at the tranny will actually tie them together, the grounding conductors from both systems, the grounded conductor from the SDS and the GEC will be jioned.

 

[Smart $]

Your system bonding jumper at the tranny will actually tie them together, the grounding conductors from both systems, the grounded conductor from the SDS and the GEC will be jioned.

The system bonding jumper and the GEC connection are not required to be in the tranny enclosure, though they can be.

 

[Smart $]

You can connect it directly to the case if you so choose.

I agree. Because the grounding conductors (primary and secondary) are of two different systems, it is not required they be directly bonded to each other.

 

[infinity]

Since the conductor in the primary feeder is an EGC you can terminate it as you would any EGC, there are no special requirements for transformers.

 

[cheaptape]

Thanks for you help

Thanks for you help