Emt

[pv_n00b]

I've seen a lot of PVC used for conduit for residential PV in Hawaii due to the environment. I have also seen my share of it turn into a melted mass during a house fire. It's pretty useless for protecting anything once it gets a little of that sweet BBQ action.

 

[electrofelon]

Agreed. For many cycles now, the Code has required metal raceways and similar for dc PV circuits inside a building, largely to protect these conductors against inadvertent damage where their path is not visible. (Say when a firefighter is ventilating a roof.) That is also the logic for marking where these conductors are embedded in building surfaces.

But exposed outside the building, those circuits are easy to trace. So the metal only requirements do not apply. The obvious example is where you have exposed single-conductor cables in free air. PVC is most common in rooftop applications in coastal environments, where metal conduit simply won't last. But you can use it more generally. (I wouldn't use it on the outside of my house, but I'm getting ready to put a bunch of it underground and it sure is cost effective.)

The title of 690.31(G) may have changes in NEC 2014, but the intent hasn't changed in so far as where metal is or isn't required. It is required specifically where dc PV circuits are run inside a building or structure. jaggedben is reading this correctly.

I always new the intent of the code, and doubted that their intentions changed in 2014...I was just being nitpicky, whiny, and difficult :angel: