277v. junction box in dwelling unit

[LuisC]

I can not find anything in the NEC that states that you can not have a 277v. junction box for exterior 277v. building lighting outside of a residential high rise. Does anybody know of a code section that says you can not have it......or maybe not being able to have a juncion box that does not serve purpose to the apartment having to be accessed from that particular apartment for maintenance purposes?

 

[480sparky]

Is 410.75 or 41080 (2005) what you're looking for?

 

[RUWired]

410.75 only limits the the higher voltage fixtures to the interior.

 

[Jim W in Tampa]

why would an apartment complex even have 480 /277 ?Cost in x formers would be crazy

 

[carlosgarcia662]

no sense double check your tester reading unless you have a warehouse or factory below I never saw such a thing ,becarefull 3phase no game to play.

 

[LawnGuyLandSparky]

why would an apartment complex even have 480 /277 ?Cost in x formers would be crazy

In many congested, older cities, 277/480 is the ONLY service the utility will provide, especially a hirise. Not enough room in the streets or cable ducts to bury the cables or transformer vaults to provide 120/208. Utility's 480 volt equipment provides 2x the power for the same space.

 

[RB1]

Section 210.6 provides the limitations for voltage ratings on branch circuits. I don't see anything that would apply to a junction box.