Solar charge controller is randomly restarting

[melbaylon]

I'm trying to figure out why my solar charge controller is randomly restarting. I have a 5 panel series string connected to a 48V 60A solar charge controller. The string of panel's output (voltage, amperage and wattage) all fall under the SCC's specifications.

I have yet to properly ground the panels. But I kinda ruled that out as the cause of the problem because I had because the SCC was not randomly restarting when I only had 3 panels in the string. But I may be wrong. Do you have any suggestion on what I should look into to solve my problem. Thanks!

(The first 3 panels in the picture worked flawlessly with the SCC. I only started to have the random restart problem when the last 2 ones were added to the string.)

 

[sunshine_eggo]

Just to confirm, are you certain the series Voc of the panels, not the Vmp, is under the PV voltage limit for your SCC?

Have you tried removing the 2 new ones and confirming the other 3 perform as they did before.

Datasheets for your hardware would help.

 

[Bud Martin]

How about providing us the make, model, spec of the SCC and the PV panels, and other equipment connected in the system?
Are you sure you are not exceeding the SCC PV input Voltage, especially when it is cold?

 

[melbaylon]

Just to confirm, are you certain the series Voc of the panels, not the Vmp, is under the PV voltage limit for your SCC?

Have you tried removing the 2 new ones and confirming the other 3 perform as they did before.

Datasheets for your hardware would help.

Yes. The total Voc of the 5 panels are at 133.25V. The SCC can handle 150V max Voc.

I did. It was fine with just the 3. The 3 older panels + a new one also exhibited the same random restart problem.

I can compile them if that helps. Just datasheets for the panels and SCC?

 

[melbaylon]

How about providing us the make, model, spec of the SCC and the PV panels, and other equipment connected in the system?
Are you sure you are not exceeding the SCC PV input Voltage, especially when it is cold?

Sure. I'll compile those.

To answer your question though: The total Voc of the 5 panels are at 133.25V. The SCC can handle 150V max Voc. I have the same random restart problem even with just 4 panels (3 older ones, 1 new one; total Voc of 106.6V).

 

[Bud Martin]

Please provide the info as we requested. Is it ALL-IN-ONE SCC/INVERTER type?
Does the SCC show any error codes?
When you say the SCC goes into shutdown, what exactly does it do? The display goes blank? Shows no charging current?

 

[MichaelK]

Yes. The total Voc of the 5 panels are at 133.25V. The SCC can handle 150V max Voc.

I did. It was fine with just the 3. The 3 older panels + a new one also exhibited the same random restart problem.

I can compile them if that helps. Just datasheets for the panels and SCC?

The panels have a Voc of 133 at room temperature, or 77F. As panels get colder, their voltage goes up. Right at freezing, the temperature compensation for panels is 1.12X, or 149Voc. What are you November temperatures like? The 106V wiring though in post #5 is a bit harder to explain? What might help is a full shutdown. Disconnect the battery from the unit and let it go stone cold. Then boot it up on battery power only. Once booted, reconnect the panels, but don't use 5 in series. See if the problem still occurs with just 4 in series.

 

[melbaylon]

Please provide the info as we requested. Is it ALL-IN-ONE SCC/INVERTER type?
Does the SCC show any error codes?
When you say the SCC goes into shutdown, what exactly does it do? The display goes blank? Shows no charging current?

Hi there. Just wanted to let you know that I'm compiling everything you asked for. I also did some further testing and now also have a video of when the SCC restarts.

 

[melbaylon]

Apologies, I forgot to get back to the people here. I did manage to solve my problem by using another SCC (PowMr 60A) that can take the voltage of my series string. I'll use my older SCC soon on panels with lower voltage. Anyways thanks again for the help.

 

[melbaylon]

I found out just yesterday that the SRNE ML4860 solar charge controller that I have is the same as the Renogy Rover 60 (Manual).