5kV and 480V cables in same pull box

[mull982]

For a new installation there are several conduits stubbing up from underground directly into a large pull box. The cables passing through this box are mostly 480V cables, however there is one set of 5kV cables routing through this box. I believe that this is a code violation due to the fact that you cannot have 5kV cables in the same raceway as cables rated for 600V, and in this case the box would be considered the raceway.

What if a flexible conduit sleve was put inside the box for the 5kV cable to pass through? In other words all the 480V cables would be pulled in the box, and the 5kV cable would be in flexible conduit inside the box. Would this meet code? Would this be considered a seperate raceway?

 

[K2500]

Does 300.3 (C)(2) exeption(e), Apply to your situation?

 

[K2500]

I should have said, 300.3(C)(2)(e)

 

[mull982]

Does 300.3 (C)(2) exeption(e), Apply to your situation?

No, this is just a typical sheet metal pullbox that I am referencing.

 

[RUWired]

You might have a hard time passing article 300.3(C)2.

Conductors of circuits rated over 600 volts, nominal, shall not occupy the same equipment wiring enclosure...

With 5 kv cables you might be ok but, you should also look at 314.71(A) or (B) for the minimal size box.

Rick

 

[Harry C]

The insulation of all cables in the box have to be of the same voltage rating. So if they are all not 5KV rated insulation then this is a code violation. But I think you can get by this problem with putting a divider in the box to seperate the 5KV from the 480 volt. Some one correct me if I'm wrong.

 

[Mr. Wizard]

The insulation of all cables in the box have to be of the same voltage rating. So if they are all not 5KV rated insulation then this is a code violation. But I think you can get by this problem with putting a divider in the box to seperate the 5KV from the 480 volt. Some one correct me if I'm wrong.

I know that on a smaller scale a divider is permissable. I'm installing two single pole switches, one 120v for plugs, and one 277v for lighting, and I have a divider installed between the switches. I can't recall the name of the company that makes them, but I bought the dividers at the supply house. Maybe you could get the sheetmetal guys to bend you a divider out of some sturdy steel. Use machine screws to install it, and I don't see why that wouldn't be considered a separate raceway. Just a thought

 

[Harry C]

The generator install I just did I had the feeders from the generators and the low voltage control wires running through the same box. All the inspector said I had to do was install a divider in the box between the 2 and I was good to go. I did what you said Mr. Wizard. I got my sheetmetal fabricator to make me up some dividers and tech screwed them in place.

 

[K2500]

Im inclined to say 300.3(C) covers this issue.

What if a flexible conduit sleve was put inside the box for the 5kV cable to pass through?

Nothing seems to prohibit that.

 

[Mr. Wizard]

The generator install I just did I had the feeders from the generators and the low voltage control wires running through the same box. All the inspector said I had to do was install a divider in the box between the 2 and I was good to go. I did what you said Mr. Wizard. I got my sheetmetal fabricator to make me up some dividers and tech screwed them in place.

:smile: I'm happy it worked out for you. Just watch the tech screws, though. I get a little antsy when I have sharp screwheads anywhere around my wire.

 

[Harry C]

I run the screws from the inside out. I with ya on the screws around wire. Not a good combination at all.