Series versus Parallel

[Ravi]

Well it is going to fail. You have done about every thing wrong so far. One huge eror is you assume you have 5 sun hours. You do not have anything close to that especially if the panels only get 8 hours of direct light a day. Only in June/July does your area even get close to 5 sun hours and that is only if you have complete unobstructed veiw of the East West South horizon, perfect solar south orientation, and optimum tilt angle where sun falls on the panel surface from sun up to sun down. . Come November-December, January and February will be 2 hours and less.

Off grid battery systems are designed for worse case. Come winter when your sun hours fall to less than 2 hours (less than 1 in your case with obstructions) your batteries will be dead and you will be in the dark all winter needing to buy all new batteries next spring. That is when you will discover you need a lot more panel wattage and much larger batteries.

Right now you do not even know how many watt hours you need in a day or Sun Hours have.

I have had 7 of these panels running for 2 months (all wired in parallel) and have been on solar completely during the day. I had been using 4 batteries (400Ah total) and calculated that I should be able to run in the evening for about 2 hours (I assumed a 10% battery consumption before the inverter shut down due to low voltage). Sure enough, my calculations seemed to be inline with my observations. During the day, I was completely on solar (producing about 700 watts, consuming 500 and charging the battery with the 200). I used a 5000w PWM inverter from Harbor Freight which I got for $350. Soon as I began hooking up more motors (furnace, sumb pump etc.), the inverter gave out. This is why I am going with an industrial inverter so it can handle a surge for a longer time.

[SunEagle]

I have had 7 of these panels running for 2 months (all wired in parallel) and have been on solar completely during the day. I had been using 4 batteries (400Ah total) and calculated that I should be able to run in the evening for about 2 hours (I assumed a 10% battery consumption before the inverter shut down due to low voltage). Sure enough, my calculations seemed to be inline with my observations. During the day, I was completely on solar (producing about 700 watts, consuming 500 and charging the battery with the 200). I used a 5000w PWM inverter from Harbor Freight which I got for $350. Soon as I began hooking up more motors (furnace, sumb pump etc.), the inverter gave out. This is why I am going with an industrial inverter so it can handle a surge for a longer time.

So let me get this straight. You have burned up a $350 inverter and are draining your batteries to the point the inverter shuts down due to low voltage.

I would give your (probably expensive) battery bank another month before it will fail to fully charge and then stop charging at all. Those probably cost you about $800. It must be nice to blow $1000 on a system that is not set up correctly. Good luck with your new industrial inverter.