I'm looking to build a unit to monitor a 12V battery in a access control panel. I wonder if this uint will work? Funny that a $3000.00 panel can't and the company says won't do it but I'm stuck with them (have over a 100 of them). My problem is the batteries are the only back up and I have no way of monitoring them. I want to build a unit that will disconnect the battery, put a load on it, if it drops below a certain voltage make an out put. I have inputs and outputs on my access panels that will communicate with the control console. Any help would be a appreciate.