4160v and 480v duct bank

[cukele]

Does the Nec allow 4160v and 480v conduits in the same duct bank and if so is 7.5 in spacing suffiecient? The only duct bank ref I have found is 310.60.

 

[charlie b]

You can have 4160V and 480V circuits in the same conduit, provided that the conductors serving the 480V circuits have insulation systems rated for 4160 volts. So being in separate conduits within the same ductbank is not a problem.

 

[Smart $]

Does the Nec allow 4160v and 480v conduits in the same duct bank and if so is 7.5 in spacing suffiecient? The only duct bank ref I have found is 310.60.

See 300.3(C)(2)...

 

[LawnGuyLandSparky]

I've only seen duct banks owned by utilities. 208 up top, and 12,500 - 347KVA on the bottom.