system bonding jumper

[deflstc03]

I have a 3-phase 480 volt to 120/208 volt Y xfmr. There is a copper strap that bonds the core to the enclosure. Do I have bond XO to my equiment grounding conductor brought from my 480 volt panel and also building steel and water pipe system? If I don't will I have unsafe system?

 

[SierraJ]

The answer is yes, you will have to terminate the equipment grounding conductor for the 480V feeder at one of two locations; 1) the grounding lug at the conduit insulating bushing or 2 at the ground lug inside the transformer enclosure.

However it is very important as you already mentioned, that this equipment grounding conductor can not substitute the required grounding electrode conductor going to the nearest ground electrode (pipe, strutural steel, etc.)