cable tray or "similar fitting" partition requirements, NEC 690.31(B)

[ryangittens]

I have a metal structure on which modules can be installed on top. The structure itself is hollow metal which we want our conductors to pass through. The structure incorporates AC lights which means AC conductors in addition to the DC PV source circuits would run in the column.

Does NEC 690.31(B) apply here? I assume the structure would be under the "similar fittings" in the section and would require a partition.

Am I correct and if so, does anyone have a reference on what the partition requirements are?


Thanks!

 

[jaggedben]

I think the partition rule applies. But I'm not aware of any codification of what the partition has to be. An expedient solution might be to to pull some flexible conduit through the hollow spaces and then run your source circuits through that.

 

[ryangittens]

I think the partition rule applies. But I'm not aware of any codification of what the partition has to be. An expedient solution might be to to pull some flexible conduit through the hollow spaces and then run your source circuits through that.

Got ya. Pulling flex through might be a bit challenging.

Do you know what the reasoning behind having a partition is?

 

[jaggedben]

Got ya. Pulling flex through might be a bit challenging.

More challenging than inserting some other kind of partition?

Do you know what the reasoning behind having a partition is?

Not really, but a guess is that it is (a) to prevent DC voltage from faulting onto AC wiring (or vice versa), and b) to help ensure that if someone wants to shut down power to safely work inside an enclosure, they are not confused about which wiring is powered from which source(s).

 

[ryangittens]

More challenging than inserting some other kind of partition?



Not really, but a guess is that it is (a) to prevent DC voltage from faulting onto AC wiring (or vice versa), and b) to help ensure that if someone wants to shut down power to safely work inside an enclosure, they are not confused about which wiring is powered from which source(s).

OK, that makes sense. Thanks!