Wireway fill issues

[rhamblin]

I need to feed 20 3-phase circuits. I was going to run a wireway down the length of the press, and drop out with cord drops. But then I read 376.22B that states over 30 conductors and I need to derate...substantially. Well I don't want to do that. So my question is, if I ran a divider down the middle of the trough, and put half of the conductors on one side and the other half on the other side, would that make it code compliant?

 

[infinity]

That's been debated here many times before. For boxes the NEC is clear, for code purposes a divider makes a single box into two boxes. For a wireway, which is a raceway, no such distinction is given.

 

[Cow]

We've done two gutters side by side chase nippled together at intervals to get around the 30 conductor requirement. It's not glamorous, but it works.

 

[augie47]

Brings up an interesting point to which I don't have a solid answer.
Assuming the loads are motor loads, is it permissible to use the Art 430.22 ratings for the required ampacity ?
For example, if we have 5 HP 480v motors where the motor circuit conductors must have an ampacity of of 9.5 amps. #12 THWN-2 with over 41 conductors has an adjusted capacity of
10.5 amps. Would this not be Code compliant (even though you might be on a 20 amp GFSC device)

 

[infinity]

Brings up an interesting point to which I don't have a solid answer.
Assuming the loads are motor loads, is it permissible to use the Art 430.22 ratings for the required ampacity ?
For example, if we have 5 HP 480v motors where the motor circuit conductors must have an ampacity of of 9.5 amps. #12 THWN-2 with over 41 conductors has an adjusted capacity of
10.5 amps. Would this not be Code compliant (even though you might be on a 20 amp GFSC device)

Good point, for motor loads you only need to size the conductor at 125% of the motor HP ampacity from the appropriate table in Article 430. The size of the OCPD wouldn't be relevant to the conductor size.