I'm planning to set up a solar power system for my RV, which is already pre-wired for solar. I have space for seven 150W panels, although I initially wanted to fit eight, it's just not working out for me right now. Each panel has an open circuit voltage of 22.6V and a short circuit current of 8.91A. The RV's pre-wiring uses 10-gauge wiring. Additionally, my solar generator can handle a maximum input of 2000W, 150V, and 34A. What would be the best way to configure my panels, likely in a series-parallel setup, especially given that I have an odd number of panels? Are there any specific concerns I should be aware of? Also, just to clarify, my max solar input is 2000W, as I mistakenly wrote 1000W earlier.
2 Answers
Since you have seven panels, your options are somewhat limited due to the prime number. You could wire all panels in series, but that might exceed the voltage limit of your charge controller at around 158V. Instead, you might consider running two series strings of three panels in parallel, giving you a combined voltage of about 67.8V with a current of 17.8A. Or you can just go with six panels in series, which gives you around 135.6V—still under the limit and close to your solar input maximum!
Just make sure you're not exceeding your wire ratings. Keep the amps below 25 and you should be good!
I agree with the series-parallel suggestion. The 10-gauge wiring is sufficient, but keep your amperage below the 30A limit for safety. If you do use all seven panels, consider making adjustments based on voltage drops you might experience. And don’t forget, each setup will depend on your actual consumption needs, so think that through.
That sounds like a good plan! Just be sure to measure everything out to account for those voltage losses.
Thanks for the heads up! I’ll keep that in mind while wiring everything up.
Got it! That's definitely a safer approach. I guess I'll stick with the six in series and maybe figure out what to do with that last panel later.