Service wire sizing

[Wattstopper]

In an exactly identical install would the wire size needed for a commercial service be any different? If I was doing a 200a single phase requiring 3/0 then my three phase wiring would require 3/0 as well, no?

 

[augie47]

There are some exceptions, but that would be the case most of the time.

 

[George Stolz]

Are you talking about houses versus commercial services? A house can use 310.15(B)(7) resulting in a smaller wire size.