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Solar Panel Mega Mystery (need a sherlock!)

Solar Panel Mega Mystery (need a sherlock!)

Solar Panel Mega Mystery (need a sherlock!)

(OP)
Greetings, I just replaced a 120W panel with a new 130W panel via a warranty. 130W was all the manufacturer had. When I hooked the system back up, my charge controller read 0.00. The second I removed the new panel, it went back up to normal of around 20.3. That is the mystery. Here are some facts.

The solar system is 24V. The 120 and 130W panels are 12V wired in series. I get plenty of voltage at the junction box on the back of each panel, and I get a bit more down at the junction box where the panels are linked to the other panels in the array so I know I don’t have a break in the line somewhere.

I double checked the run of the wiring, and all is as it should be based on the manufacturers recommendations and how the system was set up previously.

Obviously you need more information to help me troubleshoot this, so what is it that you need to know?

The system is NOT grid tied, and powers my cabin.
Thanks for all your help. - Shane

RE: Solar Panel Mega Mystery (need a sherlock!)

IT really, REALLY,  R E A L L Y  sounds like you hooked the new one up backwards.  That is exactly what would happen.  Check your panel's open circuit and make sure you're wiring the + to the - of the next panel.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Solar Panel Mega Mystery (need a sherlock!)

I think you found your Sherlock.

Best regards

Dr Watson




Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: Solar Panel Mega Mystery (need a sherlock!)

That would be my first check also.
respectfully

RE: Solar Panel Mega Mystery (need a sherlock!)

(OP)
Thanks for the advise. I will check it out first thing in the morning before the sun get too potent. :) I am not sure how this is possible, as I checked the line several times, but I suppose it is possible that the manufacturer switched the terminals from the older 120W panel to the new 130W panel. But i dont see why they would do that?

 AT any rate, it is easy enough to test. :)

If you dont hear from me, call the wife... I am out below the array being zapped by green energy. :)

RE: Solar Panel Mega Mystery (need a sherlock!)

Another possibility is that the new panel is open circuited.
Defective units DO get shipped in new boxes.
This would be my second check.
respectfully

RE: Solar Panel Mega Mystery (need a sherlock!)

(OP)
How do I check if the new shipped panel is open circuit?

RE: Solar Panel Mega Mystery (need a sherlock!)

All you need to do is unhook the panel (one terminal) and if there's any light on it at all - measure a volt or two. It can't put out a voltage if it's open circuit.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Solar Panel Mega Mystery (need a sherlock!)

As Keith says. But you should also put some load, an incandescent lamp for instance, across the voltmeter. An open panel may not be completely open - just having a high internal resistance. So a voltmeter will show a voltage if used alone.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: Solar Panel Mega Mystery (need a sherlock!)

(OP)
I have a 24V DC Light Bulb, I can use do place a draw on each panel. I will add that between the volt meter.

How does one distroy a panel anyways? For example what would hapen if I reversed the wires in teh compiner box? Pos to neg and then neg to pos? Can that be tested or if there is juice running through the system, will I fry something?

Thanks so much for all you advice, this forum is great. :)

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