Using 4/C Wire for oversized ground (3/C+G)

[death900]

I need to run in cable tray with two parallel sets of conductors that will require a ground size larger than what multiconductor typically offers and dont have time to order with oversized ground.

I am looking to order 4/C wire, use 3 of them for phase conductors (no neutral required), and the 4th phase conductor as the oversized ground (assume proper labeling will occur). Likely abandon the undersized ground provided in the cable. Do you see any reason why this cannot be done from a code perspective?

I am trying to find a blocker in the code but i am not seeing a reason why i could not do this.

 

[charlie b]

I think it's OK. What I don’t know is whether you would have to mark the 4th conductor in some fashion that shows that is the "EGC." I don't have my code book handy, but I think there are rules for color-coding the EGC.

 

[augie47]

agree with charlieb
250.119
(B) Multiconductor Cable. Where the conditions of maintenance and supervision ensure that only qualified persons service the installation, one or more insulated conductors in a multiconductor cable, at the time of installation, shall be permitted to be permanently identified as equipment grounding conductors at each end and at every point where the conductors are accessible by one of the following means:

 

[death900]

Yes! Thanks guys, i found this myself as well.

 

[texie]

Can you meet the requirements to use the cable tray as your EGC? Might be simpler and cheaper.

 

[death900]

Unfortunately no. We are transitioning to conduit underground at one instance so the purpose was to be able to run in tray without need a full sized ground in the tray. 250.119(B) gives us this flexibility.