Routing of different voltage feeds through a 4x4 junction box.

[plopez11598]

I had a vendor bring a 480VAC 4 wire circuit and a 120vac 3 wire circuit through conduit to a junction box, all wires run from there to another J box before two manual knife disconnects where they separate into their own conduit again. Is mixing of the two different voltage branch circuit in the same conduit a violation, maybe 300.3? What are the guidelines, section numbers I shoul reference if not?

 

[Dennis Alwon]

As long as the voltage of the wire is at least as high as the higher voltage then it is not an issue. Basically you are using 600V conductors for both. Now they must be marked appropriately--- look at 300.3(C)(1)