ECN Forum Forums General Topics of the Trade General Discussion Area 200a conductor sizing

I have always believed the (s) applies to multifamily dwelling feeders since you have more that one feeder but each feeder supplies one dwelling. If these reduced sizes apply to all feeders what is the word main for? 4/0 AL conductors would still be permitted for a 200 amp feeder if the calculated load does not exceed 180 amps but a 2/0 CU conductor would require a 175 amp overcurrent device.

aldave,
If you want to use a neutral that is smaller than your phase conductors for this installation you will need to calculate the neutral load. See 220.22. The equipment ground for this feeder would be sized according to table 250.122 which requires a minimum #6cu for a circuit protected by a 200 amp overcurrent device.

Curt

I have to go with the larger conductors. 310.15 (B)(6) says Main power feeder to a dwelling unit, once you start going to sub panels I don't think this article still pertains and you are back to 310.16.

I'm not disputing you triple, merely sitting the fence.

I'm aware the issue had been hotly debated pre-'02 , resulting in some minor typographical changes

This seems a terminology issue....

Is there anything currently* in the rop's on this?

*no pun intended.....

Hello Triple,
I find Stallcup's books, and Mike Holt's very informative in regard to Electrical wiring. They are tops in the field. I've heard them both talk, and Stallcup is a walking Code book.
I can't say enough about them.

Hello Triple,
I find Stallcup's books, and Mike Holt's very informative in regard to Electrical wiring. They are tops in the field. I've heard them both talk, and Stallcup is a walking Code book.
I can't say enough about them.