My friend has a solar array of 20 x 200w panels and they feed through a 150/100 controller with a 5000w Multiplus and a 750ah wet cell battery.
We live very remote and I would like to help him understand how the panels should be configured: should they just be series or series and parallel.
Can someone give advice on how best to utilise this panel array. Is the one controller adequate or should it be different and if so how.
There's not enough information here to give a proper answer, sorry.
We need at least the panel specifications, battery voltage. But your friend is probably in the danger area of high panel voltage which requires professional advice for a safe installation.
There is an online Victron solar calculator which can answer some questions, but it will require some expertise to use.
You will need to know the maximum battery charge current. Can it handle 100 amps? More? Less?
What nominal battery voltage are they running? 12v? 24v? 48v?
What are the panel specs?
Assuming, at that panel wattage, that they are 12v panels, they are probably around 24.3VoC and around 10amp imp. So the maximum panels in series is 6 for that MPPT.
If running a 12v system:
- The maximum wattage that MPPT can handle is 1450w.
- You could "over panel" the system at 1600 panel watts via 4 series, 2 parallel.
- You're still only able to use 8 of the 20 panels you mentioned.
If running a 48v system:
- The maximum wattage that MPPT can handle is 5800w.
- You could use all 20 panels if you did 4 strings of 5 panels in series. You would have to feed them into a combiner box and run some really thick 8AWG wire from the panel array to the MPPT.
Don't kill yourself handling 140v!
Please read what I said more carefully. I gave the theoretical max. I didn't actually recommend 6 in series. In fact after that I listed 2 theoretical recommendations based on assumptions on the panel and battery specs, neither of which said to put 6 panels in series.
Personally, I go with maximum voltage the MPPT can use. Depending on the Voc of the panel, I'd likely go with 4S x 5P, assuming a Voc of no more than 35V. The MPPT will limit the current accordingly but over-volts will put it into error. Just read the specs and do the maths.
The answer is quite easy. Victron provides an Excel sheet:
https://www.victronenergy.com/upload/software/VE-MPPT-Calc-4_0.xlsm
