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#121795 - 08/22/05 08:57 PM Up On The Roof
Webmaster Offline


Registered: 10/07/00
Posts: 3142
Loc: NY, USA
Apparently there was a problem with the underground feeders and they decided it would be cheaper to go over the roof. When we proposed a repair the customer's reply; "No, we haven't had any problems so lets wait until we need to make the repair." 408V 3P Parallel feeders. They must have decided a straight line was not a good idea.

Bill (LearJet9)

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#121796 - 08/22/05 09:00 PM Re: Up On The Roof
BigJohn Offline

Registered: 03/06/04
Posts: 352
Loc: Boston, MA
Reason # 271 Why I Hate PVC


#121797 - 08/22/05 10:24 PM Re: Up On The Roof
CTwireman Offline

Registered: 02/07/02
Posts: 839
Loc: Connecticut, USA
Ok, let me play devil's advocate.

Yeah, it's ugly, but I don't see any code violations other than the lack of expansion couplings. That would explain the separation.

Furthermore, if there was a problem with the underground feeders, this may well have been an emergency fix done in a hurry to get the power back on.

I look at this and say "What's the big deal?"


#121798 - 08/23/05 01:16 AM Re: Up On The Roof
e57 Offline

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
I get the feeling that the roof is newer than the wacky run. I may have been straighter before the roofers pulled it to one side for thier work, and never put it back. The other stuff on the roof being a bit more rigid, they just lifted up, splid new roofing under, and put it back down. The very slinky PVC they just dragged around, after all, whats it gonna do? Leak?

I will eventualy fail, that guys just hoping its after he retires.
Mark Heller
"Well - I oughta....." -Jackie Gleason

#121799 - 08/23/05 04:20 AM Re: Up On The Roof
LearJet9 Offline

Registered: 04/24/05
Posts: 196
Loc: Millis, MA USA
e57 is correct. The roof is newer than the PVC installation. CT is also correct. The PVC "repair" was an emergency installation when the UF failed.

#121800 - 08/23/05 10:27 AM Re: Up On The Roof
John Crighton Offline

Registered: 05/16/05
Posts: 172
Loc: Southern California
Judging from the corrosion on the straps, that "emergency" repair has been there a long time.

I don't think you can blame the PVC itself -- a properly cemented joint is as strong as the base material. (It says here on this can...)

It looks like maybe the S-curve might actually have been intentional, to mitigate the expansion effects. I wonder how much curvature you'd need to eliminate expansion joints? Would the wood sleepers eventually rub their way through the roof?

#121801 - 08/23/05 06:10 PM Re: Up On The Roof
renosteinke Offline
Cat Servant

Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
A good illustration as to why our local code requires exposed conduit on roofs (like this) to have a ground matter what the material.


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