Ok, I have a Zig CF9 unit. I have a Durite split charge system. I have a 240v hook up. A leisure battery. A starter battery. In any of this is there a way to charge the starter battery when hooked up on a campsite with 240v? I get that the Durite system will charge the starter, then leisure when driving from the alternator, but I'm concerned in case I get a flat battery somewhere on our trip. The Zig control panel has switches from 'caravan battery' to 'car battery', mains On/Off and Touring On/Off. Where does a Ctek charger come into all of this? Much obliged.