Wed, 24 Jun 2026 18:25:23 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276061#Comment_276061 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276061#Comment_276061 Thu, 10 Oct 2019 11:47:10 +0100 nigel
One consistently produced about 10% less than the other, I discovered one panel was overheating (using IR Camera).
After much waiting and not getting any joy from installer I have given up and decided to go directly to manufacturer.

They insist on the serial number of the panel before you can make a claim.
So the only way was to take panel off and obtain serial number.

When removing I discover that instead of connecting "faulty" panel into the string they had connected it to itself ie shorting it out.
The string was then connected up missing out this panel.

The question is the panel now knackered from being shorted for a considerable period of time.

Anyone?

Thanks]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276065#Comment_276065 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276065#Comment_276065 Thu, 10 Oct 2019 12:16:05 +0100 djh https://electronics.stackexchange.com/questions/18092/solar-panel-short-circuit

I'd suggest testing it, and if that's OK connect it back in and see what happens (it won't take the inverter overvoltage or anything will it?). Off the top of my head, I'd say it was worth advising the manufacturer what you found but perhaps worth reading their technical docs and warranty first to see if they mention anything.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276066#Comment_276066 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276066#Comment_276066 Thu, 10 Oct 2019 12:24:12 +0100 nigel
I have no idea if that panel is generating anything though.

I will have to compare production over the next week and see if it compares more favourably with the other system.

If I hadn't had another identical system there is no way I would have identified the problem in the first place.
I wonder how many other installations have either faulty panels or poor installations and there is little you can do to make sure its working properly unless you have access to an IR camera maybe.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276069#Comment_276069 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276069#Comment_276069 Thu, 10 Oct 2019 15:21:19 +0100 djh Posted By: nigelI wonder how many other installations have either faulty panels or poor installations and there is little you can do to make sure its working properly unless you have access to an IR camera maybe.
In the case of my system I can see the production of each individual panel, and so can Enphase, who manufacture the microinverters. So they should alert me if they detect a problem.

In general though I've found the PVGIS system is pretty accurate at predicting system output, so I might be able to detect a problem using that, though it would take some time.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276093#Comment_276093 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16275&Focus=276093#Comment_276093 Fri, 11 Oct 2019 17:09:05 +0100 jamesingram VOC ( open circuit voltage) should be close to spec irrespective of irradence
Isc (short circuit current) is proportional to irradence.

If you test one of the other panels at the same time that would give you the figure your looking for.

You could test at the isolators for the same , total figure for each array , that's what the installers should have done and they should have spotted one wasnt connected.
You're dealing with high DC voltages there though so not for the novice.]]>