Solar Panels Drop Frequently to Zero Amps?

[azimuth551]

Need some assistance with my RV Trailer set up. First off here is my configuration: 4-6-Volt Batteries for 12V; 4-100W Renogy Panels wired in 2S2P; Renogy Rover 40Amp MPPT Charge Controller. This system has been working very well for a couple years and I have recently decided to add two more panels for those cloudy days. I just installed the panels and hooked the same as the others, 3S3P. When I hooked up the system, I got a full voltage of around 37-40volts, 22-26amps, 350-420Watts in full sun, maybe not an ideal angle. All the sudden the amps and watts drop to zero after reaching the peak watts and then comes back and drops again after a few seconds. I went ahead and changed my controller to a Victron 100/50 thinking that was the issue but it is doing the exact same thing. Batteries were not fully charged and the victron says absorption. I also programmed the charge controller for my battery specifics--Rolls 6v Batts for 12volts. Panels: Renogy: Voc=22.3v; Vmp=18.6v; Imp=5.38a; Isc=5.86a. I must add that I did some testing for each group. I connected only my new set and it was perfectly fine and producing power with no drops. Next I added another set and all was well. I disconnected one of them and connected the other older set and everything was fine. When I connected all three sets or six panels, the drop outs started again.
Any ideas on what the issue could be?

 

[acdoctor]

Need some assistance with my RV Trailer set up. First off here is my configuration: 4-6-Volt Batteries for 12V; 4-100W Renogy Panels wired in 2S2P; Renogy Rover 40Amp MPPT Charge Controller. This system has been working very well for a couple years and I have recently decided to add two more panels for those cloudy days. I just installed the panels and hooked the same as the others, 3S3P. When I hooked up the system, I got a full voltage of around 37-40volts, 22-26amps, 350-420Watts in full sun, maybe not an ideal angle. All the sudden the amps and watts drop to zero after reaching the peak watts and then comes back and drops again after a few seconds. I went ahead and changed my controller to a Victron 100/50 thinking that was the issue but it is doing the exact same thing. Batteries were not fully charged and the victron says absorption. I also programmed the charge controller for my battery specifics--Rolls 6v Batts for 12volts. Panels: Renogy: Voc=22.3v; Vmp=18.6v; Imp=5.38a; Isc=5.86a. I must add that I did some testing for each group. I connected only my new set and it was perfectly fine and producing power with no drops. Next I added another set and all was well. I disconnected one of them and connected the other older set and everything was fine. When I connected all three sets or six panels, the drop outs started again.
Any ideas on what the issue could be?

2S2p = 4 panels 2 parallel sets of 2 in series VOC of 44.6 amps of 11pre string
3S3p = 9 panels 3 parallel sets of 3 in series VOC of 67.2 amps of 16.5 per string
3S2p = 6 panels 2 parallel sets of 3 in series VOC of 67.2 amps of 11 per string
2S3p = 6 panels 3 parallel sets of 2 in series VOC of 44.6 amps of 16.5 per string

Which of these are you actually employing that is causing the problem?

 

[Don B. Cilly]

3s3p. So almost 50A out of a 50A controller. Might be close to limit.
Does it do it in not-so-full sun?
-

 

[HRTKD]

Something doesn't add up. Even if you went 4s you would still be (barely) under the 100 volt Max PV Input Voltage of the Victron 100/50. So the Victron shouldn't be cutting out due to overvoltage. 6 panels with 600 watts total at around 12 volts would be 50 amps, which is well within what the 100/50 can handle. I have 640 watts going into the same controller, no problem.

I'm thinking the wiring of the panels is suspect.

 

[Supervstech]

More likely a connection issue with the bank.
I would inspect each and every connection.