August:As discussed, PVC is sometimes the best solution in a corrosive environment. I would never recommend supporting PVC as depicted in the photos. Shooting a screw through comp roofing is questionable at best. Better methods of installing PVC are available, including better straps and painting for UV protection.
I might add that although I would not tolerate brown PVC, UV browning does not render the conduit unusable. The browning is only a few microns thick. This is why the conduit says "UV resistant".
For hangers, I suggest a better anchoring system. We use aluminum strut with stainless fasteners and hangers. From our previous life as a tower rigging firm we have brought over stainless telecommunications hardware: http://awapps.commscope.com/catalog/andrew/product_details.aspx?id=13158 This is available in various sizes
William Miller At 11:26 AM 10/9/2009, you wrote:
Content-Language: en-US Content-Type: multipart/related; boundary="_004_29A77A075EE0674CB6040A8B3B716734AAC371AAMBX04exg5exghos_"; type="multipart/alternative" All PVC doesnt hold up well in the Bay Area Heres a photo of some ~4 year old PVC browned PVC from Marin County:83877e5.jpgYou can see that the straps melted resulting in the conduit sliding down. Thank goodness we didnt install this. PCV seems like a good option for shaded areas.As Bill pointed out, if we use EMT we need to bond both ends of the conduit to comply with NEC 250.97. My issue is that it is hard to find outdoor rated bonding bushings thats why weve just been installing cast metal boxes with threaded connections (complies with NEC 250.92(B)(2)).As William point out, EMT is robust and reliable. I still think that there must be more efficient way to go between arrays. Maybe thats why commercial low profile racking systems are often fully integrated systems with built in wire raceways.-August
<<attachment: 83877e5.jpg>>
_______________________________________________ List sponsored by Home Power magazine List Address: [email protected] Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
