Makes you wonder if we just couldn't get a manufacturer to make beefier modules for really harsh sites, eh? --Chris @ the Oasis MT
_____ From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Thursday, January 12, 2017 5:22 PM To: RE-wrenches Subject: Re: [RE-wrenches] Solar World Wind Damage Chris & Dana; Our site is a mountain in Wyoming and does have some focusing effects, so maybe 170 mph is possible. Are your arrays using top down clamps? I think that is apparently stronger, also possibly the 2011 Sanyos look to have beefier frames. However, I looked at their spec sheet and they're only rated at 60 PSF (less than the SWs). From my measurements here of Solar World 4.0 frames, I'm seeing a flange thickness of approx 1.3 mm, while an old Siemens SP 75 has 1.8 mm thick metal. I'm coming up with a fix for the Solar Worlds: 3/4 x 3/4 Stainless steel Angle fits just inside the lip of the module, and will distribute the forces more evenly. The question then is, are we just going to lose the glass next? Anyone have a currently available module that is beefier? I may recommend we swap the whole array out, if we are indeed exceeding the design of the Solar Worlds. Thanks, R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 1/12/2017 2:39 PM, Chris @ The Oasis wrote: Wrenches: We have a ~70KW ground mounted array on the Rocky Mountain front near Choteau, MT. Springs winds are not unusual with 150 to 175 MPH gusts. The system was installed in 2011 (with Sanyo 215W modules). No problems yet; we certainly over-engineered the racks, knowing what high winds there are! Chris Daum Oasis Montana Inc. 406-777-4309 406-777-0830 fax www.oasismontana.com _____ From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Thursday, January 12, 2017 2:16 PM To: RE-wrenches Cc: Sefchick, Steve Subject: Re: [RE-wrenches] Solar World Wind Damage Hi Bill; Solar World customer support did come through yesterday with flying colors. They got hit by a big storm in the North West. Right now though, they are saying that we exceeded the 64 PSF rated loading to the back of the module. I've pointed out that that would correspond to over 170 mph winds, so I'm not quite ready to concede the warranty. Their engineering team is reviewing my information. As always, the Wrench list experience is invaluable. Are 170 mph winds possible, outside of a tornado or hurricane? Whether or not Solar World stands by their product in this extreme situation, I definitely stand by my installations. I'm taking a snow cat up to replace and reinforce the modules next week, then hopefully get a little help from my supply chain after. My repair costs will be many times the cost of one replacement module anyway. Yes, the 33 mm vs 31 mm refers to the module thickness. I don't have a version 2.5 frame to check the flange metal thickness, and it is conspicuously absent from the specs. I have a good micrometer, and I will compare metal thicknesses of several module brands, because with all the cost cutting, many module manus seems to be using thinner metal lately. As Jay pointed out, we're bolting much bigger modules down with much weaker flanges, and the same hardware we used on a 75 w module, so its not entirely surprising to start seeing high wind failures. R.Ray Walters
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