Good morning, I am an electronics student and sustainable energy enthusiast. I have a small PV array w/battery backup installed in my home. To fully utilize the battery power I want to connect a small heating element, approx 1.5 amp load, that will run when the battery voltage is around 12.3 volts or greater, and turn off when the voltage drops to 11.5. I'm thinking of using an op amp as a comparator, Schmitt trigger to establish the UTP and LTP, and either a zener diode or voltage reg to establish the reference 12v. I'm finding my textbook a bit confusing because it only gives examples of such circuits with AC signals. Can someone help with this design- setting ref, UTP & LTP, choosing an op amp? Thanks