Equipment ground for parallel conductors

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cdwilson1165

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Hopefully, someone will be able to give me a definitive answer on here.

If parallel conductors are run in a trench with its equipment ground and as they penetrate the ground to the equipment box in PVC conduit, does the ground have to be spliced or added to so each conduit has a ground wire in it?

300.3 does not address this, nor does 310.10(H)

Thanks
 
Each conduit must have its own equipment grounding conductor. 250.122(F)(1)(b)

(b) Multiple Raceways. If conductors are installed in
parallel in multiple raceways, wire-type equipment grounding
conductors, where used, shall be installed in parallel in each
raceway. The equipment grounding conductor installed in
each raceway shall be sized in compliance with 250.122 based
on the overcurrent protective device for the feeder or branch
circuit. Metal raceways or auxiliary gutters in accordance with
250.118 or cable trays complying with 392.60(B) shall be
permitted as the equipment grounding conductor.
Click to expand...
 
Interesting question. I agree with Dennis, in the trench a single EGC is all that is required but once you enter the raceways each raceway will need a full size EGC.

Welcome to the Forum. :)
 
That's what I was unsure about because technically the PVC's aren't considered raceways because they are not complete and are there solely for protection.
 
I wouldn't be surprised if many inspectors would look at it the way you do. Let's take the scenario and make the run 40 feet, or 60 feet then to open trench. Would that need a equipment grounding conductor? It makes more sense the longer the run of conduit but I am not sure of the intent.
 
I don't see the PVC as a sleeve it's a transition from one wiring method to another.
 
Yep, this is one of those odd situations. I agree that this is not a sleeve but rather a change in methods and would require a EGC in each raceway. Not something that I have run across but sure could.
 
If the risers are short enough, you could just put all your parallel sets in one conduit and rely on 310.15(A)(2) Exception to ignore the derating.

Otherwise, you could run the EGC through one conduit to the box, and splice on jumpers that run back into the other conduit stubs and just terminate at the end of each riser. Because that would obviously provide practical safeguarding..

Cheers, Wayne
 
Thank you guys for the help. It's sort of a gray area in the code depending on how you interpret it. It would be nice to consolidate it all into one conduit but they are 750's, so that would be a big piece of conduit and would cause more trouble going into the cabinet. We'll continue with the splices and grounds going into each conduit. I was trying to eliminate the need for the wire and burndy crimps. We have 27 conduits per cabinet so that cost adds up.
 
Is there a large, perhaps rectangular raceway that could work? Something like a trough with no ends, stood on end?
 
If there is no transition clamp fitting or box at the bottom end of the PVC sections, that is a strong argument that they are sleeves rather than complete raceways.
If you terminate the PVC at a horizontal plate and then run the wires from there into the box using appropriate cable clamps in the box but not on the PVC you have an even stronger argument that the PVC sections are just sleeves.
 
The problem with that argument is that 300.5(D)(1) requires cables emerging from grade to be protected by "enclosures or raceways". And 250.122(F)(1)(b) refers to conductors installed in multiple raceways. So it doesn't matter whether the raceway segments are sleeves or not.

I like Larry's suggestion of using one large enclosure or raceway to protect the conductors from the minimum cover depth upwards.

Cheers, Wayne
 
wwhitney said:
The problem with that argument is that 300.5(D)(1) requires cables emerging from grade to be protected by "enclosures or raceways". And 250.122(F)(1)(b) refers to conductors installed in multiple raceways. So it doesn't matter whether the raceway segments are sleeves or not.

I like Larry's suggestion of using one large enclosure or raceway to protect the conductors from the minimum cover depth upwards.

Cheers, Wayne
Click to expand...

That would be one hell of a raceway to replace 27 runs
 
LarryFine said:
Must a sleeve be a "listed" item, or could, say, a white 10" PVC DWV pipe be used?
Click to expand...
300.5(D)(1) requires an "enclosure or raceway". I don't believe 10" PVC DWV pipe is either of those.

If 310.15(A)(2) Exception applies, then instead of 27 conduits going up, maybe (3) or (9) 6" PVC conduits would suffice, and reduce the required EGC splicing?

Cheers, Wayne
 
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