New 480v service

[rawlands]

I am installing a 120/240v 1phase 200a panel in a new building. Since the power company xformer is 480v and 1100' away, the plans call for a 480v service to be installed, then a 480-120/240 xformer to be installed at the site. I realize i must pull a neutral to the 480v service disconnect, but since i will not even utilize it, (other than fault current) how much can i undersize the neutral?

 

[iwire]

See 250.24(C)

Specifically 250.24(C)(1)

 

[JWCELECTRIC]

Is it possible to extend the primary cable overhead by POCO to the new building and then step it down to 240/120 single phase? May save on voltage drop, copper costs, and the POCO may pick up some of the cost on the extention.

 

[charlie]

Or maybe they will hang a pole mounted transformer for you at 120/240 volts. :smile: