I may have over upgraded. 1000watts of panels connected to a 40A SCC

[Sean Steele]

I managed to get in on one of the products from one of Will's videos and now I'm not sure if I went too far. I got four 250W Santan Solar panels. That's 1000 watts total. I figured I'd connect them in 2S2P to keep the voltage under 100VDC that the charge controller is rated for. However, I missed the other spec on the controller that says Max PV Power for a 12 V system is 520W. Will the controller just not use the extra power or will burn something up? I assume I won't get the full rated watts out of the panels but probably between 700-800 watts on a good day.

Panel and SCC specs attached

 

[Bud Martin]

You can try 3 panels in parallel, that should be OK. I had my 12V 40A MPP Solar using three 230W panels (690W) connected in parallel and able to get 520W for long hour during the day and even when it is cloudy.

 

[Sean Steele]

I had considered doing something like that too but 750 or 1000, I'm not sure if the Renogy Rover has current throttling. I may just get a second Rover 40 and run two parallel panels thru each. Might help mitigate issues with partial shadowing.

 

[chrisski]

I would say 1000 watts is way too overpaneled.

With four in series 100 watts max, I think you will likely exceed the SCC rating for several hours a day. Your SCC should have a rating in there somewhere for how much it can be over paneled. My Victron 100/50 has a max PV amp input rating of around 60, which is about 20% over-paneled. I don't know what happens if its exceeded.

I do have three SCCs in my system in part to mitigate shading as you mention, but in another part because I ran out of room for the sized panels I wanted installed.

 

[Bud Martin]

I had considered doing something like that too but 750 or 1000, I'm not sure if the Renogy Rover has current throttling. I may just get a second Rover 40 and run two parallel panels thru each. Might help mitigate issues with partial shadowing.

Page 24 of the user manual regarding to the PV curent:
The controller will limit the battery charging current to the
maximum battery current rating. Therefore, an over-sized
solar array will not operate at peak power.

Using two SCC is a good second choice.

 

[Hedges]

Wired 2s2p and all four panels aimed directly at the sun, it might peak at 1000W on a cold day.
With each 2s string oriented differently, e.g. 10:00 AM and 4:00 PM sun for a 90 degree angle, it will peak at 700W.
That's STC; PTC should be about 595W so pretty close.
If you put a 60 degree angle between them (8 hours, like 9:00AM and 5:00PM), peak would be 500W on a cold day, 425W more typical.

The angled panels will give more hours of good production but fewer total Wh/day (assuming larger enough charge controller) because sun below the horizon gets clipped, and path through atmosphere is longer.

I think 1kW of panels is a good fit if you use multiple orientations.

 

[time2roll]

Flat on the roof collecting dust and periodic shade.... I would connect as you said 2s2p and let it rip. Solid 40 amps all day long