Single Condutor in cable Tray- Equipment Ground Conductor Requiremnt

Status
Not open for further replies.
F

faresos

Senior Member
NEC 392.10(B)(1)(a) indicate the single conductors smaller 1/0 AWG are not allowed for use on cable trays in industrial establishments. Article 392.22(B)(1)(d) doesn't recognize any conductors less than 1/0. I have a feeder run that consists 4#3/0 & 1#3Gn (single conductors) that will be installed on cable tray. My question is: does the limitation of using minimum size conductor (#1/0) is also includes the equipment ground conductor? in another word, do I have to change the #3G conductor to 1/0 or there is an exception for equipment ground conductors that we can use smaller size than 1/0?

Thanks,
 
faresos said:
NEC 392.10(B)(1)(a) indicate the single conductors smaller 1/0 AWG are not allowed for use on cable trays in industrial establishments. Article 392.22(B)(1)(d) doesn't recognize any conductors less than 1/0. I have a feeder run that consists 4#3/0 & 1#3Gn (single conductors) that will be installed on cable tray. My question is: does the limitation of using minimum size conductor (#1/0) is also includes the equipment ground conductor? in another word, do I have to change the #3G conductor to 1/0 or there is an exception for equipment ground conductors that we can use smaller size than 1/0?

Thanks,
Click to expand...

You can use listed PV wire of any size in a cable tray. 690.31(C)(2)
 
Found Article 392.10 (B)(1)(c) which states equipment grounding conductors are permitted in cable trays and needs be #4AWG or larger. Does the equipment ground needs to be TC rated?
 
The feeders will be transitioned from cable tray to conduits so I have to have insulated equipment ground for each run. Do they make #3 TC rated?
 
faresos said:
Does the equipment ground needs to be TC rated?
Click to expand...
No.

faresos said:
The feeders will be transitioned from cable tray to conduits so I have to have insulated equipment ground for each run.
Click to expand...
Besides the requirement of 392.10(B)(c), why would it need to be insulated just because it's going in a conduit?



Roger
 
roger said:
No. (Roger, is there any section in the code says it doesn't have to be or this is just from your passed experience with this type of installation?

Why would it need to be insulated just because it's going in a conduit? (it doesn't have to be but that's what the client requested)

Roger
Click to expand...

Thanks,
 
Carultch said:
Bare wires cause abrasion during pulling. Not an NEC requirement, but possibly a job spec or an experience judgement call.
Click to expand...
I've never had that problem pulling bare copper.

Roger
 
faresos said:
Roger, is there any section in the code says it doesn't have to be or this is just from your passed experience with this type of installation
Click to expand...
Faresos, simply by the allowance to use a "bare" conductor implies the EGC does not need any special listing.

Roger
 
Carultch said:
You can use listed PV wire of any size in a cable tray. 690.31(C)(2)
Click to expand...

Which ampacity rules would apply to small single conductors if not explicitly stated in 392? My opinion is that I can follow the rules for multiconductor cables as a conservative take. Using 65% of free air table is arguable as well.
 
Andrew445 said:
Which ampacity rules would apply to small single conductors if not explicitly stated in 392? My opinion is that I can follow the rules for multiconductor cables as a conservative take. Using 65% of free air table is arguable as well.
Click to expand...

This is uncharted territory in the the NEC. For the most conservative strategy, I would simply pretend it is in a raceway and follow the standard feeder ampacity calculation.
 
Status
Not open for further replies.
Top