Just bought a new Caravan to drag along (Swift Challenger)and although I have the main electrics, I'd like to now add the auxillary socket (12S) to charge the 'vans battery/run the fridge, etc whilst on the move.

Although I understand the principles, I'd like to know if anyone has done this and whereabouts did they wire the +ve 12v to save the caravan's battery acting as a slave to the main one when starting up (high currnt draw) and blowing any inline fuses/melting wiring or whatever! TIA.