I just looked at a job small commerical space, that is 3 phase 4 wire. They are think of putting a bigger panel. Do I have to pull in a another wire. It is pipe all the way back to the disconnect. I was think of just using a bonding bushing to the grounding ternimal of the new panel. But reading 250.32(D) I don't think I can do this. I think I need to pull a another wire. Or is this 3phase 4 wire ok. The disconnect is in a electrical room on the other side of the wall. I didn't know if this was grandfather, building was built in the70's.
250.32
- Thread starter guschash
- Start date
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mcclary's electrical
Senior Member
- Location
- VA
The pipe is your EGC
- Location
- New Jersey
- Occupation
- Journeyman Electrician
If it's a metallic pipe.
Yes as mcclary said you can use the metallic conduit as an EGC. Unless this is 277/480 with concentric or eccentric KO's standard locknuts are all that you'll need to meet the bonding requirements.
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