Peter323 said:Can somebody point me to an explanation of when to bond the neutral with the ground in the panel board.
Thanks for your help.
iwire said:Was that panel supplied directly from a transformer?
tryinghard said:It's easier to understand starting from when you can't, check out:
250-24(A)(5)
250-142(B)
250-32(B)(1)
Compared to when you can:
250-30(A)(1)
250-32(B)(2)
Peter323 said:No it was not. It was wired to a meter bank about 80' away. It is a condo building where each floor has a common utility room with meters and disconnects.
hillbilly said:Is there a main disconnect ahead of these "sub panels"?
Peter323 said:Yes, there is. At the meter.
hillbilly said:Let me get this straight.
You have a multi-floor condo building.
Each floor has one utility room that contains a meter bank supplying a seperate meter and disconnect for each condo on that floor.
From each disconnect, there is a dedicated 4 wire feeder to a breaker panel in each condo.
Each breaker panels supplies only the circuits in that condo.
Your "electrician friend" has bonded the grounded (neutral) and equipment grounds in each sub-panel, and also bonded the building steel from each sub-panel....correct?
steve
tryinghard said:In your situation you cannot bond the neutral unless you meet all the criteria of 250-32(B)(2), and I understand you are not involved with a transformer therefore 250-30(A)(1) does not apply.
I also understand your situation is one building and 250-32 is for two or more buildings; see 250-142-(B) and 250-24(A)(5)
"A grounding connection shall not be made to any grouded circuit conductor [neutral] on the load side of the service disconnecing means"
&"Except as permitted in 250-30(A)(1) and 250-30(B), a grounded circuit conductor shall not be used for grounding non-current-carrying metal parts of equipment on the load side of the service diconneting means"
&Do not bond the neutral, if done erroneously it will dangerously cause current to flow where it does not belong
Peter323 said:Basically yes, the only difference is that there only a 3-wire feeder because the conduit is used as the ground electrode.
crossman said:Conduit is used as a grounding electrode? Or do you mean Equipment Grounding conductor?