Don’t connect a window AC unit to your small off grid solar power system. I did and ran the batteries down to 12% state-of-charge. Since I do not make a habit of this the batteries should bounce back but it was a good lesson to learn. The system was saved by an email warning I received from the MorningStar TS-MPPT-60 charge controller.
http://www.morningstarcorp.com/products/tristar-mppt/
Post time: Jul-02-2017