Grounding Both sides of a metal nipple between panel and disconnect

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Transportation Guy

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Location
Williamsburg,VA
We were failed today for not having a bonding bushing on both ends of a 4" close nipple that is between our panel and disconnect of a 277/480 3 phase service. I know code reference 250.92A and B and have been gigged for this before but not in a long while. Most say this should not fail. Any opinions? In the nipple are 3 phase conductors a neutral and EGC. We did not utilize a concentric knockout. We drilled a 4" hole to meet our needs.

I read 250.92(B).2 to say 1 bushing will be sufficient.


I also utilized 250.97 due to the voltage.
 
I agree also additional bonding beyond a standard locknut is required on one side only. Since you have fully punched KO's then one bonding locknut on either side would also work.
 
I'm sorry, it's been a long day so humor me.
If it's between a disconnect and a panel, unless its a non-fused meter disconnect, is 250.92 applicable ? Sounds like feeder conductors to me and 250.96
 
augie47 said:
I'm sorry, it's been a long day so humor me.
If it's between a disconnect and a panel, unless its a non-fused meter disconnect, is 250.92 applicable ? Sounds like feeder conductors to me and 250.96
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Good point if this is beyond the service disconnect then standard locknuts will suffice.
 
Assuming that it is an EGC and not actually your GEC that is ran through the nipple, I wonder if this is not where the AHJ is hung up.



250.62(E)(1)

"Ferrous metal raceways and enclosures for
grounding electrode conductors shall be electrically continuous
from the point of attachment to cabinets or equipment to
the grounding electrode and shall be securely fastened to the
ground clamp or fitting. Ferrous metal raceways and enclosures
shall be bonded at each end of the raceway or enclosure to the
grounding electrode or grounding electrode conductor. Nonferrous
metal raceways and enclosures shall not be required to be
electrically continuous."

Or he may be thinking "Inductive Choke" which would be a single bare grounding conductor ran through a ferrous raceway.
 
ActionDave said:
If they are tightened up properly they do.
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I would have to agree Action Dave. However, he specifically sited 250.97 (B) and 408.37. In his own words.... He said he doesn't see a sealing lock nut as an option to provide continuity as required.


This is a 6 story hotel with the same inspector coming out for the next year multiple times per week. I am "choosing my battles". He is also the chair of our local EC continuing education class and dinner we have monthly and is a great inspector.
 
I'm actually unsure if it is a violation, but I can see his concern.
 
Transportation Guy said:
I would have to agree Action Dave. However, he specifically sited 250.97 (B) and 408.37. In his own words.... He said he doesn't see a sealing lock nut as an option to provide continuity as required.


This is a 6 story hotel with the same inspector coming out for the next year multiple times per week. I am "choosing my battles". He is also the chair of our local EC continuing education class and dinner we have monthly and is a great inspector.
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I understand the dance that goes on between us and the inspectors. If he is a good guy and one you can talk to that's great.
 
Transportation Guy said:
I would have to agree Action Dave. However, he specifically sited 250.97 (B) and 408.37. In his own words.... He said he doesn't see a sealing lock nut as an option to provide continuity as required.


This is a 6 story hotel with the same inspector coming out for the next year multiple times per week. I am "choosing my battles". He is also the chair of our local EC continuing education class and dinner we have monthly and is a great inspector.
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a good friend to have...... and not someone to annoy unless absolutely necessary.

i've taken a GRC nipple, put two couplings on it, and two chase nipples,
and as long as it's below energized components... used it to couple stuff
together. some inspectors are good with it, some aren't.

two couplings are cheaper than two myers hubs....
 
augie47 said:
I'll risk being 'kwired' and repeat another's post.. post 5 applies
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I'll chime in here and say that post 5 and post 8 apply:)

Transportation Guy said:
Thanks for all the responses. He failed us because we used sealing lock nuts and they dont provide continuity. Makes sense. My guys didn't tell me they were sealing locks.
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Did you ask why they have those "teeth" that dig in to the surface of the enclosure, even enough to scratch through painted surfaces so that they make good contact?

Maybe show him some white page listing information on them? (don't know what you will find, but would bet they are listed for bonding.)

Add:

Did you have 4 sealing locknuts or did you have regular locknuts inside enclosures and sealing locknuts on outside of enclosures?
 
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