RFR #1 - What gives?

[miahallen]

We'll give it a shot.

edit - didn't change anything

[Halfcrazy]

Ok so for some reason there appears to be no power available. I am at a loss as to what the issue is but it all points at the PV modules in my mind anyhow.

Can you post some more pictures of the combiner box from lots of angles? and maybe some pictures of the wiring on the modules?

[miahallen]

Yes, it is the panels...I hooked up a standard 230W poly panel (1st pic) this morning and it reacted normally.  The panels we are using in the system are Abound Solar 70W thin film technology (2nd pic).  They were purchased used from GGS for $0.42/W.  The panels visually look normal, and the open circuit voltage is normal.  How else can we test these panels?  They are currently mounted 30ft in the air in custom build frames with 12 panels in each frame...so they are not easily managed.

[ClassicCrazy]

I was thinking you would want to disconnect each panel and test not only the open circuit voltage but also short out the leads and use a DC amp meter to test the short circuit current too. But sounds like it might be hard to do with how you have them mounted.

Can you turn off one string at a time to see if one of them is causing the problems - if so at least you could isolate that one and still have some charging.
Larry

[Halfcrazy]

I also wonder if it may be the connectors on the panels. Will take some time to test out but if you do as Classic Crazy suggested and physically plug each panels - into its + and short it out then use a clamp meter to test for current. I would test every panel this way

[miahallen]

This morning, I ran short circuit tests on each of the 12 strings.  None of them performed as expected.  There was scattered clouds while I was testing, and when the sun was obscured…some of the strings would output about 0.8A as expected, when the clouds moved away, the amperage would increase to about 2.3A as rated…but then the amperage would suddenly drop to 0.  I witnessed this on 7 of 12 strings, the other 5 strings never revealed any output.

[Halfcrazy]

Wow. So that was per string or per panel? I would break it down to each panel and see if you can determine how many are bad.

[miahallen]

That was per string...Breaking it down per panel would require disassembling the frames...which it looks like we will have to do at this point :-(

[ClassicCrazy]

I have no experience with thin film panels. But I just looked up problems for them
Page 90 to 91 has some info
http://www.isfh.de/institut_solarforschung/files/iea_t13_review_of_failures_of_pv_modules_final.pdf

Guess lesson learned for everyone is to test each used ( and new ) panel before putting them up, especially in hard to access locations.

Larry

[ClassicCrazy]

Afraid you may have some bad news about your solar panels - I just saw this article ...

Internal documentation and testimony from sources within Abound show that the company was selling a faulty, underperforming product, and may have mislead lenders at one point in order to keep itself afloat.

“Our solar modules worked as long as you didn’t put them in the sun,” an internal source told The Daily Caller News Foundation.

Read more: http://dailycaller.com/2012/10/02/sources-documents-suggest-government-subsidized-abound-solar-was-selling-faulty-product/#ixzz3iFmYv698

[Doug]

Well, there ya go. Just keep them in the shade and they will perform as well as any other panel, or a rock for that matter.

-D

[dgd]

Well, there ya go. Just keep them in the shade and they will perform as well as any other panel, or a rock for that matter.

Errr, thermal mass rock structures, walls, gables, beds etc., are more efficient at heating and cooling than a dud PV or even a working PV and of course much cheaper 

dgd