Electrical – Requirements for Surface mount raceway using THHN


At the top of a 14' wall in a private residential (non commercial) work shop, I'd like to run about 100' of surface mount raceway, with THHN conductors inside of it. I plan to use 4"x4" raceway, for about 10-15 conductors (Despite being relatively large, it fits the space perfectly). I've read code saying you can put conductors in a raceway, but nothing that specifies any physical properties of that raceway. Can I use relatively lightweight PVC raceways with removable covers, similar to what I'd use for data cabling? (As seen in the picture) If not, what defines acceptable raceway?

Additionally, my plan is to knock out holes, and connect to the solid non-removable surface of the raceway using rigid conduit, for load center connections, surface mount outlets, etc. (In the same way I'd connect to any junction box). Is that acceptable?

Because of the out of the way location of the raceway I'm not worried about it being physically damaged, but I want to make sure the lightweight PVC raceway is acceptable from a code perspective.

California, USA
Solid wall raceway

Best Answer

I use raceway quite often. With a 20% max fill and no need to derate if your current carrying conductors are less than 30 total it is easier to lay cables in than pull in some cases and no derate is the big advantage.

For exterior raceway it will need to be listed for sunlight or UV protected I have used pvc in the past but most of my work is heavy industrial where metal is needed to protect from impacts. Metal holds up better better but in your case a plastic wire way makes sense to me.