<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Thanks everyone for your insightful replies, have passed them on to the customer with comments. He only wants to try and get another 6 mo. out of the panel until he can afford to replace it; and as always there are circumstances to consider. Unfortunately his shop burned due to arson and no insurance coverage so money is tight.<div><br></div><div>Ron</div><div><br><div><div>On Sep 1, 2014, at 4:30 PM, Ray Walters <<a href="mailto:ray@solarray.com">ray@solarray.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
<meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type">
<div bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">I've done patch jobs on little 12 v
systems, and had them hold up for many years, but I concur, I
wouldn't try that at higher PV voltages.<br>
Silicon sealant actually is slightly conductive, at least
according to other Wrenches when this subject came up several
years back.<br>
<pre class="moz-signature" cols="72">R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified PV Installer,
Licensed Master Electrician
Solar Design Engineer
303 505-8760</pre>
On 9/1/2014 2:43 PM, Martin Herzfeld wrote:<br>
</div>
<blockquote cite="mid:CAJDha9qmPhT3UO124MMa+Sy5KO1R8tMNPOjh2hmcYOv4wwNEAw@mail.gmail.com" type="cite"><p dir="ltr"><br>
I concur with Dan. Unless a controlled environment, a patch job
on a module with a customer is wrong on so many levels.</p><p dir="ltr">Martin Herzfeld<br>
California Solar Contractor License #833782<br>
Trenching Contractor, Pole Installation & Maintenance,
Instrumentation</p><p dir="ltr">UL Certified PV Installer #17, OSHA 30<br>
Principal Contract Solar Technical Inspector<br>
OSHA-Authorized Construction Trainer<br>
CompTIA Certified Technical Classroom Trainer (CTT+)
#T3NSZCNBBKB4QTQG<br>
Project Contractor & Consultant</p><p dir="ltr">Telephone & Text: <a moz-do-not-send="true" href="tel:510-243-0190">510-243-0190</a></p><p dir="ltr">Ron,</p><p dir="ltr">It's been my experience the only adhesives that work
reliably on PV backsheets are those designed for the purpose,
such as Dow 804 et. al.. Substances such as silicone sealant,
tool polymerics, and others will appear to be suitable when
first applied, but they eventually peel loose over a period of
1-5 years.</p><p dir="ltr">Issue #2: Heat of sufficient temperature to melt the
backsheet may also have been hot enough to affect solder joints
on and among the cells. Crystallized solder connections will
conduct current, but are more resistive, and eventually will
degrade due to heating and cooling, leading to overheating and
eventual failure. Then too there's a possibility of
micro-fractures created in the cells due to the heat, which take
time to become apparent, but will also cause a PV module to quit
working .. or at least quit working at its rated specifications.</p><p dir="ltr">Issue #3: When PV are manufactured, the layers at a
minimum are manufactured from tempered glass, EVA, cells and
buss, EVA, then the backsheet (tedlar, kevlar, etc.), in that
order. The module is assembled under conditions of heat and
vacuum. With the backsheet melted, the environmental integrity
of the laminate has been compromised, allowing ambient humidity
into the PV. While it may be functional now, long-term
prospects for continued proper operation are questionable at
best.</p><p dir="ltr">Unless there's a pressing reason to try to salvage
the module, it's better to replace it.</p><p dir="ltr">Dan Lepinski</p><p dir="ltr">--------------------------------------------<br>
On Sun, 8/31/14, Ron Young <<a moz-do-not-send="true" href="mailto:solareagle@solareagle.com">solareagle@solareagle.com</a>>
wrote:</p><p dir="ltr">Subject: [RE-wrenches] PV panel backing<br>
To: "RE-wrenches" <<a moz-do-not-send="true" href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a>><br>
Date: Sunday, August 31, 2014, 6:32 AM</p><p dir="ltr">Hello Wrenches,</p><p dir="ltr">I have an installation of 165w PV on a pole mount
that was exposed to a fire from the rear when the customers shop
burned. 6 of the 10 panels survived with only replacement of the
MC4 plugs required but one of the panels that is still
functioning had the rear coating melted off. The cells and
electrical grid still function. Can anyone recommend a
replacement coating that may salvage this panel for a few more
years. I know if left exposed it will soon deteriorate but am
wondering if some kind of commonly available non conductive
rubberized or latex type of coating might do the job?</p><p dir="ltr">Ron Young</p><p dir="ltr">_______________________________________________<br>
List sponsored by Redwood Alliance</p><p dir="ltr">List Address:<a moz-do-not-send="true" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a></p><p dir="ltr">Change listserver email address & settings:<br>
<a moz-do-not-send="true" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a></p><p dir="ltr">List-Archive:<a moz-do-not-send="true" href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a></p><p dir="ltr">List rules & etiquette:<br>
<a moz-do-not-send="true" href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a></p><p dir="ltr">Check out or update participant bios:<br>
<a moz-do-not-send="true" href="http://www.members.re-wrenches.org/">www.members.re-wrenches.org</a></p>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
List sponsored by Redwood Alliance
List Address: <a class="moz-txt-link-abbreviated" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a>
Change listserver email address & settings:
<a class="moz-txt-link-freetext" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
List-Archive: <a class="moz-txt-link-freetext" href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a>
List rules & etiquette:
<a class="moz-txt-link-abbreviated" href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a>
Check out or update participant bios:
<a class="moz-txt-link-abbreviated" href="http://www.members.re-wrenches.org/">www.members.re-wrenches.org</a>
</pre>
</blockquote>
<br>
</div>
_______________________________________________<br>List sponsored by Redwood Alliance<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br><br>Change listserver email address & settings:<br><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br><br>List-Archive: <a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a><br><br>Check out or update participant bios:<br>www.members.re-wrenches.org<br><br></blockquote></div><br></div></body></html>