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Posted By: shortcircuit Metalic Raceway Grounding - 05/29/05 12:36 AM
I have been installing PVC underground to supply outdoor branch circuits. PVC makes for a speedy installation.

I have had some of this PVC damaged from impact, including SCH 80 where it emerges from ground.

I want to use a piece of ridged conduit only where it emerges from ground and change right back to PVC.

Does the code require this short section used for physical protection to be bonded to the grounding conductor of the branch circuit?

shortcircuit
Posted By: Joe Tedesco Re: Metalic Raceway Grounding - 05/29/05 01:28 AM
Yes.
Posted By: Gregtaylor Re: Metalic Raceway Grounding - 05/29/05 02:05 AM
I can never find this code article when I need it, including now, but Joe is right. If you use a short piece of rigid in a run of PVC (some guys like to use rigid 90's including me) the only way it doesn't need bonding is to be 24" or more underground.
Posted By: Joe Tedesco Re: Metalic Raceway Grounding - 05/29/05 03:34 AM
See 250.80, Exception, and 250.86, Exception No. 3
Posted By: Gregtaylor Re: Metalic Raceway Grounding - 05/29/05 03:55 AM
Oops. 18".
Posted By: gfretwell Re: Metalic Raceway Grounding - 05/29/05 04:32 AM
Can you drop a short sleeve of RMC over the PVC where it is subject to "severe" damage.
Posted By: George Little Re: Metalic Raceway Grounding - 05/29/05 05:34 AM
Greg- I like that idea of slipping a piece of RMC or IMC over the PVC. And you wouldn't even have to bond it [Linked Image]
Posted By: shortcircuit Re: Metalic Raceway Grounding - 05/29/05 09:56 AM
gfretwell...I too, like that sleeve idea and will try it!

250.86 exception #2 allows short sections of metalic raceway to be ungrounded where used to protect cable assemblies...

So, if it where UF wire emerging from ground, then no bonding...

But, if the raceway encloses individual conductors for the branch circuit, then bonding is required...

Do we agree?

shortcircuit
Posted By: harold endean Re: Metalic Raceway Grounding - 05/29/05 01:48 PM
I asked an EC for that same idea. He had an underground 400 amp service and where the pipe came up through the floor in the basement, he sleeve the PVC riser with Ridgid and he didn't have to worry about his kids ( or anyone else) hitting the PVC riser and cracking the pipe. I think this guy went even one better and stuck some concrete inside of the RMC.
Posted By: Active 1 Re: Metalic Raceway Grounding - 05/29/05 05:14 PM
What is the advantage Of sleving the PVC with RMC compared to using only RMC at the stub up? I seen it specked out but just never seen any advantage.

Tom
Posted By: walrus Re: Metalic Raceway Grounding - 05/29/05 08:28 PM
I would say the advantage to sleeving pvc with RMC is no bonding
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