String Configuration Question ?☀️

[Lighthouse Beacon]

Hi Everyone,
Long time lurker here, but it's my first post. Ill attached my setup here:






I've got (24) of these panels. I had originally wanted to just run 12S and 12S to an inverter, but I am having trouble finding the right inverter. I am on a budget and this system is abit of just a fun project. My main goal was using the panels to shade my vehicles. I had an generator load panel I am going to pump into after the inverter.
I was leaning towards getting (1) 6.5KW BluePower SP6548 SOLAR INVERTER / CHARGER, and eventually adding another when I can afford it, so I can get 220v.
Is there anyway I can get all these panels into just (1) SP6548.



I think I would have to do 6 panels in series, 2 strings into input 1, then 6 panels in series, 2 strings into input 1. Would I be safe doing that? I found this in the literature. I am in South Florida, I shouldnt see freezing temps here.




Thank you so much for your time. I am trying to do my best to do my homework. I am just nervous I won't make a very good decision or I will damage something. Feel free to recommend another inverter as well. The folks at Sungold Recommended this one, but it's a POWMR with a new paintjob and I've seen some bad reviews on this rig. https://sungoldpower.com/collections/power-inverter/products/8kw-off-grid-solar-inverter-ul1741

 

[Hedges]

I don't like that tall board which will cast a shadow on the panels. Unless it is one of the funny panels where cells form a large number of stripes length of panel, so shadow on edge only takes out production from the edge.

41.3Voc x 12 panels = 495.6 Voc string
I'll assume +16% in freezing weather, unless you have temperature coefficient from PV panel data sheet and your location's record coldest temperature.
495.6 Voc x 1.16 = 575Voc in cold temperatures.

390 VDC max allowed PV voltage. You're right, it doesn't work.
There does not appear to be a short current max limit for PV input to inverter. Just 4000W per input, which is usually a guideline not a rule.

Consider 6s2p and 6s2p into the two PV inputs. That will be 287V max, 206 Vmp, 19.2 Imp, 3963W (STC) so expect maybe 70% to 85% of that typically.

 

[pvgirl]

Yes 2 arrays of 6s2p will be fine.

 

[Hedges]

I don't like that tall board which will cast a shadow on the panels.

Or the posts, for that matter. Think the architect would be offended if I took a chain saw to them?

As for shading by the boards, a few options come to mind:
1) Cut the boards down (was their width needed for strength)?
2) Block all the panels up to height of board edge.
3) Just block up that edge of panel to height of board edge. Slightly different slope of panel won't matter, but eliminating the shadow is good.

Shadow from house also isn't good. Maybe tilt those panels. That does get to be a steeper angle. Angle of shadow toward rear of picture indicates roof slopes up, can't beat that much height. Just have to live with it. Maybe put those six most affected panels in one string, so it drops out of production. Next six paralleled with it, also partially shaded. the other two sets of six away from the roof can work better together.

 

[Lighthouse Beacon]

Or the posts, for that matter. Think the architect would be offended if I took a chain saw to them?

As for shading by the boards, a few options come to mind:
1) Cut the boards down (was their width needed for strength)?
2) Block all the panels up to height of board edge.
3) Just block up that edge of panel to height of board edge. Slightly different slope of panel won't matter, but eliminating the shadow is good.

Shadow from house also isn't good. Maybe tilt those panels. That does get to be a steeper angle. Angle of shadow toward rear of picture indicates roof slopes up, can't beat that much height. Just have to live with it. Maybe put those six most affected panels in one string, so it drops out of production. Next six paralleled with it, also partially shaded. the other two sets of six away from the roof can work better together.

Thanks Hedges!
Yes you are exactly right about the design. It's definitely not built for performance in mind. I built it myself with the focus being a shaded carport and an array second. To be honest, my wife is not a big fan of looking at solar panels on the property so this was my solution to make everyone happy. LOL. Yes alot of shade from poles! But I was told it made it prettier! haha. All great comments my friend, thank you. Maybe one day I can get a big enough property to have some real fun. I am in South Florida so I rarely see clouds, which helps. We havent had freezing temps here in decades so should be good on cold panels.

 

[Lighthouse Beacon]

Yes 2 arrays of 6s2p will be fine.

Thank you for your reply!