cross building circuit?

[anbm]

Building A and B belong to the same owner. Each building has separate service.

Can we feed some branch circuits (20A/1PH, 120V or 277V) in building A from an electrical panel in building B? (because the panel in building B stays closer to the load). Thanks!

 

[raider1]

Check out 225.30 for your answer.

Chris

 

[anbm]

Thanks for the hint, this makes me wondering if the building has emergency generator as backup power source... then, should we need to have separate generator for each building or they can share one generator. 225.30 rule only address normal power service, I assume.

 

[hurk27]

Thanks for the hint, this makes me wondering if the building has emergency generator as backup power source... then, should we need to have separate generator for each building or they can share one generator. 225.30 rule only address normal power service, I assume.

You can use a single generator to feed two or more buildings, but you will have to use separate transfer switch's for each building.

 

[hurk27]

Check out 225.30 for your answer.

Chris

Yea it seems to say that, but what is confusing is then why we need 225.37?

 

[don_resqcapt19]

I don't see anything that says I can't have a service and a feed from a second building. In general, I can't have more than one of either, but I think the code permits one of each. The rules in 230 do not apply to feeds from a second building and the rules in 225 do not apply to services.

 

[Dennis Alwon]

I believe 2011 allows it.

225.30 Number of Supplies. A building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means shall be supplied by only one feeder or branch circuit unless permitted in 225.30(A) through (E). For the purpose of this section, a multiwire branch circuit shall be considered a single circuit. Where a branch circuit or feeder originates in these additional buildings or other structures, only one feeder or branch circuit shall be permitted to supply power back to the original building or structure, unless permitted in 225.30(A) through (E). For the purpose of this section, a multiwire branch circuit shall be considered a single circuit.