690.31 (B)

[sketchy]

I'm looking for opinions on a future install. Does split loom corrugated tubing meet the definition of a "barrier" required in 690.31 (B)? I'm looking at possibly running AC and DC in a wireway and I don't want to spend the money on a partitioned style. Thoughts?

 

[jaggedben]

I think it's probably fine. I'm not sure exactly what the intention of that requirment is and I think it meets the dictionary definition. I've seen some pretty perfunctory barriers in inverter enclosures that were seemingly intended to satisfy this requirement.

 

[electrofelon]

I think it's probably fine. I'm not sure exactly what the intention of that requirment is and I think it meets the dictionary definition. I've seen some pretty perfunctory barriers in inverter enclosures that were seemingly intended to satisfy this requirement.

Yeah fronius inverters come with some sort of protective sleeve for the AC conductors and they say something in the manual like "if required". They can operate on 1kv strings so perhaps there is a slightly stronger case for the sleeving in those situations.

 

[Carultch]

Yeah fronius inverters come with some sort of protective sleeve for the AC conductors and they say something in the manual like "if required". They can operate on 1kv strings so perhaps there is a slightly stronger case for the sleeving in those situations.

I think the OP's question is about is what to do in a wiring trough, wireway, or pull box, that you would field-install below the inverter. As opposed to what is done inside a manufactured inverter. What is done inside a manufactured inverter isn't for the installer to be concerned about, as the inverter interior is governed by the UL standard, rather than the NEC.

It is common for inverters to have all their entries on the bottom, which makes it the use wireways or troughs to collect and distribute the wires of both sides a convenient way to arrange the wiring structures, as we could do prior to NEC2014 without thinking about AC/DC separation. The onset of this rule requires a physical partition between AC and DC, but isn't very specific about just how rigid this rule is, and what manufactured product would qualify. By "rigid", I mean whether or not there is flexibility for an inch of AC wiring to have an exposed line-of-sight to DC wiring where it enters/exits the trough, even if there is no chance the AC and DC wires could even come in contact. Look up wire trough divider to see what the manufacturers have in mind for this purpose. Split-loom certainly would meet the intent of this NEC rule, as the rule is intended for preventing AC-to-DC faults, in the event that the insulation fails.