Ray:


Great thread.  Thanks for starting it.



An idea crossed my mind (and there was plenty of room in there):  If one
could find a sturdy aluminum channel that happened to fit firmly over your
module frame, one could use it along the long access, or maybe even the
short access, of the module frame to reinforce it.  Bottom mounted, the
fasteners would go through a hole in the module frame and the aluminum
channel.  The outside channel could stiffen up a module pretty
significantly.



Now the above idea may not be practical, especially if you can’t find the
right channel, but I would not be surprised if this idea maybe someone else
on the list come up with a related idea that might be better.



William









[image: Gradient Cap_mini]
Lic 773985
millersolar.com <http://www.millersolar.com/>
805-438-5600



*From:* RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] *On
Behalf Of *Ray Walters
*Sent:* Thursday, January 12, 2017 6:40 PM
*To:* RE-wrenches <re-wrenches@lists.re-wrenches.org>
*Subject:* Re: [RE-wrenches] Solar World Wind Damage



Yep, the old modules were heavier, had a thicker frame, and most
importantly: much less total surface area.   The old 75 w modules were less
than 7 sq ft, compared to almost 18 sq ft of a new 60 cell module.  2-1/2
times the forces on even thinner metal.
Not that I want to go back to the good ol' days, but I think the industry
got a little too thin on the frame, or at the least, we need a beefier
hardware solution for bottom mounted arrays on open frames in high wind
locations.  I'll send a pic of our fix, once we try it.


R.Ray Walters

CTO, Solarray, Inc

Nabcep Certified PV Installer,

Licensed Master Electrician

Solar Design Engineer

303 505-8760

On 1/12/2017 6:01 PM, Dana wrote:

Bottom side bolt up. But they were 1995 Solarex remember the weight of
those frames!



----------------------------------------------------------------------------

Dana Orzel - Great Solar Works, Inc - C - *208.721.7003*

NABCEP # 051112-136 : Idaho PV Licence # 028374

E - *d...@solarwork.com <d...@solarwork.com>*  - Web - www.solarwork.biz

"Responsible Technologies for Responsible People since 1988"

*P* Please consider the environment before printing this email.





*From:* RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org
<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
<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








_______________________________________________

List sponsored by Redwood Alliance



List Address: RE-wrenches@lists.re-wrenches.org



Change listserver email address & settings:

http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org



List-Archive: 
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html



List rules & etiquette:

www.re-wrenches.org/etiquette.htm



Check out or update participant bios:

www.members.re-wrenches.org
_______________________________________________
List sponsored by Redwood Alliance

List Address: RE-wrenches@lists.re-wrenches.org

Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: 
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out or update participant bios:
www.members.re-wrenches.org

Reply via email to