Common GEC copper bus bar 250.30A(6)a

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CustomElectricLLC

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I commonly find warehouse spaces with switchgear in an electrical room have a copper bus bar with the GEC, bldg steel, and other bonding wires landed on that bus bar (outside the service enclosure on the wall). Im installing a 2500A service in a similar warehouse setup and wanted to do a common grounding electrode as well. I have rebar which serves as the main bldg GEC, building steel bond, gas bond, water bond, riser sprinkler bond, and xfmr GEC in same room per articles I mentioned does anyone see any potential issues of such an installation granted that the GEC taps are connected to the bus bar with listed methods for grounding and bonding? Another article that I believe supports this installation is 250.64 F. Thank you
 
That's how we do it all of the time in large buildings. Typically the bus bar goes near the service and the GEC's run out to the various locations from there.
 
The nec allows a grounding bus bar, its the cleanest install, and easy to do over having 3 or 4 gecs going into panel. And it gives you the intersystem bond that is required.
I used 1 hole crimp on lugs with 1/4" ss hardware to attach to grounding bus bar. Later i can post a picture.
 
tom baker said:
The nec allows a grounding bus bar, its the cleanest install, and easy to do over having 3 or 4 gecs going into panel. And it gives you the intersystem bond that is required.
I used 1 hole crimp on lugs with 1/4" ss hardware to attach to grounding bus bar. Later i can post a picture.
Click to expand...

I think that as long as crimp on lugs are used then the installation will comply with code. Besides you can’t use a mechanical lugs on a gec, as it has to be irreversible per code. At least that’s what I’ve read. I guess my question is, if your gec from your main electrode (Rods, plate, rebar, etc) lands onto that ground bus bar the the wire that goes from the bus bar to the service is what? A bonding jumper? A splice or continuation of the GEC?


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dvpvic said:
Are you guys bonding one side of that metallic raceway? And are you guys using crimp on lugs that then bolt to the bus?
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Yes if you look closely at the photo you can see a grounding hub on the end of the raceway to the left. We use hubs on both end of the metallic raceway. Also the crimp on lugs that are being used are visible on the ground bus.
 
dvpvic said:
I think that as long as crimp on lugs are used then the installation will comply with code. Besides you can’t use a mechanical lugs on a gec, as it has to be irreversible per code. At least that’s what I’ve read. I guess my question is, if your gec from your main electrode (Rods, plate, rebar, etc) lands onto that ground bus bar the the wire that goes from the bus bar to the service is what? A bonding jumper? A splice or continuation of the GEC?


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Click to expand...

Where did you read the lug is required to be irreversible ?
 
infinity said:
Yes if you look closely at the photo you can see a grounding hub on the end of the raceway to the left. We use hubs on both end of the metallic raceway. Also the crimp on lugs that are being used are visible on the ground bus.
Click to expand...

Yes and those are two hole NEMA lugs, they are better than single hole as they don't twist
 
dvpvic said:
I think that as long as crimp on lugs are used then the installation will comply with code. Besides you can’t use a mechanical lugs on a gec, as it has to be irreversible per code. At least that’s what I’ve read. I guess my question is, if your gec from your main electrode (Rods, plate, rebar, etc) lands onto that ground bus bar the the wire that goes from the bus bar to the service is what? A bonding jumper? A splice or continuation of the GEC?


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Click to expand...

Busbars are allowed, please read 250.64, to answer your questions
 
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