Hi all. I currently have my 12v lighting etc running from the leisure battery. Even when on hook up. how does everyone get a 12v supply from the mains when on hook up that will then switch to the leisure battery when not on hook up. Not sure what to buy to do this. Zig? if so which one? Any advice very welcome.
What I've done is run a leisure battery charger from one of the 240v sockets to the leisure battery. This means that when on hookup, I can still use 12v stuff as per normal, but the 240v is charging the leisure battery up.
on hook up, if you have a Zig type unit, any juice drawn from the LB is replenished by the charger, automatically....same principle as AndyC has just mentioned
the Zig CF 9 ( often found in buses) has the benefit of being able to distribute 12v to your accessories and fridge, while on hook up, and then act as a simple distribution board when travelling, so 12v power is then provided from the LB... Also, you can 'bridge' the charging output with a fused link, so that both LB and SB can be charged simultaneously...if you forget to remove the fuse, it'll blow when you start up....for this reason, it's worth fitting a 'mini MCB' as below, if you decide to go down this route I've just been re testing my CF9, and it's charging at 13.4V on both batts....not bad for a twenty year old unit! a good source for Zigs is a caravan breakers
Your other option is something like a CTEK MSX7 or Amperor battery charger which has a "supply" mode.
run everything on 12v from the battery then use a ctex 5 or 7 battery charger to charge the battey Dont worry to much if the charger is not big or has a supply mode as it will catch up when you are sleeping
