1 Parallel Conductor

[Brandon Loyd]

With a 3 wire circuit, is it legal to run smaller parallel wire for only 1 of the 3 phases? I found this insallation and it appears they ran out of larger wire for the 3rd phase, so they just ran 2 smaller conductors in it's place. These conductors are all in the same conduit.

 

[david luchini]

With a 3 wire circuit, is it legal to run smaller parallel wire for only 1 of the 3 phases? I found this insallation and it appears they ran out of larger wire for the 3rd phase, so they just ran 2 smaller conductors in it's place. These conductors are all in the same conduit.

I don't see anything that would prohibit this, providing the parallel conductors are #1/0 or larger.

 

[charlie b]

You also have to deal with the derating associated with having 4 current-carrying conductors in the same conduit.