"Different Uses"

[jdiv]

Hello all, shedding my lurker status to ask a burning question:
225.30 says only one branch circuit can serve a seperate structure.
225.30(D) says more are allowed for "different uses", giving an example of "control of outside lighting from multiple locations".
What are your experiences with AHJ's determinations of what "different uses" means? I have a hard time believing that feeding lights would be a different use than feeding receptacles, since that kind of defeats the original point of one branch circuit. But what about a light on a detached garage switched from inside the house, or a heat detector interconnected with the house smoke alarm system?
What are your thoughts? What flies out there?
Thanks,
John

 

[ActionDave]

Welcome to the forum.

I can feed a light to the garage three wayed to the house. I have worked on a project where there was one 480V motor and the rest of the building was 120V lights and recepts so there was a 480V feed and a 240V feed to it. Other than that it's one circuit or one feeder.

 

[kwired]

Light on detached garage switched from house or vice versa - is specifically covered by last sentence in 225.30

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)

If you have complex lighting or other controls maybe consider low voltage controls or even wireless controls.