but still trying to figure out a controller that i can use to trigger a relqay with. i want one that runs on either 48dc or 120ac. one that I can read the battery voltage with and hen it gets to 54.4 volts turn on the water heating elements. let it run until the voltage drops to say 54dc and shut off the elements.
Morningstar tristar PWM on load division , or a victron battery monitor trigging a relay