[RE-wrenches] Canadian Solar "blemish"

Exeltech exeltech at yahoo.com
Wed Nov 9 19:53:04 PST 2011


Difficult to tell exactly what's up from the photo.

Gives the impression an object (e.g. hailstone) struck the PV at
the "lower center" of the cell on the left.  The impact didn't break
the tempered glass, but was sufficient mechanical shock to fracture
the two cells shown.  I've got an old Siemens 16-2000 with cracked
cells, and the pattern is almost identical.

Mavrick's comment (below) is on target.  To continue with his thought...

A quick Isc test on a clear day around solar noon comparing this PV
to adjacent (and presumably unblemished?) PV would give insight
whether or not the output current has been affected.

Dan


--- On Wed, 11/9/11, maverick at mavericksolar.com <maverick at mavericksolar.com> wrote:

From: maverick at mavericksolar.com <maverick at mavericksolar.com>
Subject: Re: [RE-wrenches] Canadian Solar "blemish"
To: "RE-wrenches" <re-wrenches at lists.re-wrenches.org>
Date: Wednesday, November 9, 2011, 9:35 PM

I have seen this pattern twice.

1. Lightning strike near the array. But the canals are bright white or deep black. I have two of those panels for testing and they still work sorta.

2. A bad batch of EVA or an over-cooked batch of EVA during assembly perhaps.  Of course, the photo does not lend itself to determining the depth of the fracture: at the glass layer, at the EVA layer or at the silicon layer.  If it is at the silicon layer, then the current would drop. 

Fort that panel, Each cell is a 0.5 volt generator at About 3 amps or so. If you crack the cell (Cleve it straight across) it becomes a 0.5 volt 1.5 amp cell. So I think it would mess with your vmp overall if the silicon was cracked.


Thank you,

Maverick


Maverick Brown
BSEET, NABCEP Certified Solar PV Installer ®
President & CEO
Maverick Solar Enterprises, Inc.
Office:     512-919-4493
Cell:        512-460-9825

Sent from my HondaJet!

On Nov 9, 2011, at 3:41 PM, penobscotsolar at midmaine.com wrote:

> Hello all,
>   We have a customer who has acquired, over the last ten years or so, a
> large array with several different makes and models of panels, all
> installed by a qualified electrician and the customer. They have done
> an excellent job as far as self installed systems go.
>   He just sent me a picture of one of his Canadian Solar 210's with a
> very unusual pattern on it (actually under the glass). The panel is
> about three years old and shows no decline in output, but he is
> concerned with the very obvious visible pattern. I have never seen
> anything like it.I've attached it to this email. Anyone?
> 
> Thanks for any suggestions or ideas,
> Daryl
> <CS210-Midkiffsm.jpg>
> _______________________________________________
> List sponsored by Home Power magazine
> 
> List Address: RE-wrenches at lists.re-wrenches.org
> 
> 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
> 
_______________________________________________
List sponsored by Home Power magazine

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

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

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20111109/908d5987/attachment-0004.html>


More information about the RE-wrenches mailing list