Mixed Wire Size

[quantum]

What does the NEC say about using different wire sizes on the same circuit? I.E. if a 30A 3-Phase load was served with 2 - #10's and 1 -#8 wire instead of 3 - #10 AWG?

 

[infinity]

As far as I know the NEC is silent, although 250.122(B) might come into play if you use a wire type EGC.

 

[iwire]

What does the NEC say about using different wire sizes on the same circuit? I.E. if a 30A 3-Phase load was served with 2 - #10's and 1 -#8 wire instead of 3 - #10 AWG?

Nothing, go for it.

You could even have one conductor of aluminum and the rest of copper as long as each has sufficient ampacity.

 

[electrofelon]

As far as I know the NEC is silent, although 250.122(B) might come into play if you use a wire type EGC.

Now that could be an interesting discussion how to apply that....