Dc and Ac voltage together

[dfm]

I was wondering if it is against code to run DC circuits from the solar array (possible 450vdc) through a trough to the inverter while having ac circuits in the same trough (inverter to meter /disconnect, 240vac)? thanks

 

[jaggedben]

Not unless you have a partition separating them. See 690.31(B). (This only applies to PV circuits. Other DC would be okay.)

Also, depending on what you mean by 'trough', that may not be an allowed wiring method at all.

 

[ggunn]

Not unless you have a partition separating them. See 690.31(B). (This only applies to PV circuits. Other DC would be okay.)

Also, depending on what you mean by 'trough', that may not be an allowed wiring method at all.

Is that what you meant to say? He asked if it would be a violation and your answer says that it would violate code if it had a partition.

 

[jaggedben]

You're right, misworded answer. It's a violation if you don't have the partition.

 

[Carultch]

You're right, misworded answer. It's a violation if you don't have the partition.

As I understand, most of the time this pertains to the application of a string inverter line-up, where all the inverters' conduit entries are on the bottom. And it is impractical to run any more than one wire trough beneath them, since you can't snake a conduit over the AC trough cover to the DC trough below it. Plus, troughs are expensive.

How rigid is this rule? Is it so rigid that not one single inch of DC and AC circuits may be in proximity without a partition?

Or as long as 90% of the length of the respective circuits are separated by a partition, it is OK?

I haven't been able to find any partitions that fit inside most wire troughs and wireways, and the easiest solution I could think of is to adhere a plastic slotted wire duct for either half of the circuits within the trough. The disadvantage is that obviously you have to enter and exit the duct within the trough, and during the entry/exit, it will be in proximity to the other half of the circuits.

Also, what is the intent of this rule?
Is it EM field isolation? Or is it simply trough organization?

Because it can make a difference on whether the partition should be metallic or non-metallic. Obviously I'd prefer non-metallic, so I don't need to even think about grounding.

 

[Carultch]

Not unless you have a partition separating them. See 690.31(B). (This only applies to PV circuits. Other DC would be okay.)

Also, depending on what you mean by 'trough', that may not be an allowed wiring method at all.

A wire trough and a wireway are very similar terms, if not interchangeable. As I understand it, a wireway is continuous, where you can splice one section to another, while a wire trough is a discrete slender enclosure, that would require conduit nipples to join adjacent factory lengths. Wireways are common in NEMA1 applications, while NEMA3R applications would often need a wire trough.