emt vs. pvc for solar

[jdubba]

I will be installing a solar (pv) system on my roof, and I'm trying to decide between emt or pvc for running on the surface of the roof, and punching down to an outside inverter (shady side of house). Any suggestions based on sunlight/ uv exposure? I live in a moderate climate in California. Thanks

 

[BryanMD]

I will be installing a solar (pv) system on my roof, and I'm trying to decide between emt or pvc for running on the surface of the roof, and punching down to an outside inverter (shady side of house). Any suggestions based on sunlight/ uv exposure? I live in a moderate climate in California. Thanks

In northern areas that would be done in rigid.
Well supported emt should be fine but I wouldn't use pvc.
If you can keep it in shade even better.

 

[peter d]

I live in a moderate climate in California. Thanks

In that case I would go with EMT.

But here in New England we would use PVC or RMC. EMT does not last long outdoors here.

 

[splinetto]

Why would EMT be better outside than PVC? Or are you just saying its better if in a place without alot of snow or rain?

 

[iwire]

In the Northeast EMT exposed outside first rusts, then disappears leaving just the conductors. This happens fairly quickly around here.


If I had any choice I would use aluminum rigid conduit. If you look at solar installs they usually use stainless hardware and aluminum frame work, they are designed for long term exposure.

 

[ultramegabob]

who makes fittings for emt that are listed for being weather tight? I know alot of people use compression fittings, but I thought they werent listed for it...

 

[ItsHot]

do it once

do it once

I like Bob's suggestion, Aluminum rigid. Do it once and be threw with it! You see a lot of rusted out emt, especially on horizontal runs along walls!:-?

 

[ultramegabob]

I guess T&B makes rain tight fittings, I just did a search and found them..

http://www.tnb.com/ps/fulltilt/index.cgi?part=5120

 

[rexowner]

If by "punching down" you mean any DC conductors
inside the building, 690.31(E) means PVC is not even
an option. I don't see a problem with EMT
outside using raintight fittings in my area in Northern
Californa.

 

[jdsmith]

The folks in Ohio use sealtite or liquidtight to run from the roof down to the inverters, but I like the aluminum rigid idea better.

 

[newenergy]

EMT is far an away the most common. I wouldn't use PVC because it looks bad imo, but it seems like it would get brittle after years in the sun. It's used underground though of course.

Aluminum rigid does sound good.