Question for knowledgeable solar experts

tvfrfireman wrote:
The system when we went to bed the next night was at 100 percent sate of charge. Turned on the inverter and was awoke at 3 am with dead batteries.

Do you have a full battery monitor that counts amp hours?

If you do, it should show the amps coming out of the battery. This is the information you need to determine why the perfectly good and fully charged batteries are getting drained quickly.

I think it could be something sneaky like the water heater electric element is on or the fridge switched to 120v power. These are thermostatically controlled so the draw may not show up immediately.

Good luck and welcome back if you dare.