pvc riser ground

[jsashley2]

On our large ground mount arrays we run our DC feeders above ground tell we get just adjacent to our inverters. At that point we put each feeder in a separate PVC conduit down into the trench. Length of about 5 feet. We are only running a single ground wire with the above ground route which may have 4 or 5 feeders. When we go underground do we need to split the ground wire and run one in each conduit then back together once we are under ground direct bury?

 

[jaggedben]

Maybe I'm misunderstanding the setup, but I would say yes, absolutely. Otherwise where is your EGC between each inverter and the array?

 

[jaggedben]

Sorry, maybe I am misunderstanding. All the wires go into the same trench and you're just using PVC to protect them on the way to the ground?

I think it all depends if the circuits end up terminating in the same equipment. If they split up anywhere and go to different inverters, see my first post. If they all land in the same enclosure where the ground lands, then the extra grounds may not be necessary, but see 300.3. (Are the PVC risers really necessary?)

 

[jsashley2]

they all end up at the same inverter. we had been running from an above ground copper clad messenger wire that was UL approved for our EGC then just continuing to run it as a single wire down past the conduits into the trench and continue on to the inverter. we got a new drawing
showing wire split into each riser than combined back together we don't see need to spit ground to run in conduit riser then combine back together riser are only there to protect the wire going in and out of the trench in the inverter we have a single ground bus bar that the EGC, so single point at both ends attaches to

 

[solarken]

690.43(C) requires EGC to be run with circuit conductors, and "be contained within the same raceway or cable or otherwise run with the PV array circuit conductors when those conductors leave the array". I interpret that as yes, the EGC needs to be split and run in each conduit, but I suppose one could argue that "otherwise run with" is met if it is outside the conduit but in the same trench.

 

[jaggedben]

It seems to me that if the PVC conduits are all snugged up to each other or nearly so, and are being used merely to add physical protection to durect burial cable, where such protection exceeds code and listing requirements, then it should be permitted to ignore the presence of the PVC with respect to 300.3 or 690.43. My argument would be that the EGC is run with the circuit conductors and that the PVC does not meaningfully change this. At any rate, I'm more or less certain it makes no difference to safety.

Were metallic conduit used, or were the separation between conduits significant, then it would be different.