configure 28 12v gel batteries for a 48v MPPSolar LV6548 system

[44bburgess]

I have 2 LV6548 systems configured for s split phase configuration. I have 28 12v/200ah gel batteries configured for 3s/16p. shutoff voltage is 46.4v and max charge is 56.4v. The batteries only last for a couple of hours. What am I doing wrong? I seem to be drawing 30kwh at night. I though I had I had 3800ah of batteries.

 

[sunshine_eggo]

3S16P = 48 12V batteries. You said you have 28.

12V @ 3S is 36V.

Maybe clarify what you actually have? Pictures?

The only 48V config you can have with 28 12V batteries is 4S7P, which would be a little nightmarish.

This would be 1400Ah.

Series: voltage adds, capacity same
Parallel: capacity adds, voltage same

You can also convert to Wh:

28 * 12V * 200Ah = 67,200Wh

67,200Wh / 48V = 1400Ah

Based on typical lead acid battery sizes, you need 7kW - 14kW of PV for proper charging.