We have used a similar system for over a decade although we only charge the batts when moving the camper between CG's. I used solid state isolator, manual reset breakers under hood and auto reset at the camper. Batteries are fully charged in 3 to 4 hours at highway speeds. 15.5 volts into the isolator 14.8 volts at the batteries. The last was measured with the truck in tow/haul, headlights on and refrig on dc. Truck was at idle. Truck batt charge line was up graded to 8 awg with 8 awg in parallel through a 2nd connector. When at the camp site we use solar to charge the batts. Some CG's with a no generator rule will also not let you idle the truck as a FWIW.
4/21/2015 update:
Had to move the camper today so did a recheck, batts were at 90% or 12.77volts, cranked the truck put in tow/haul and lights on at idle. Again 15.5 volts into the isolator with 14.8 volts out and 50 amps to the cranking battery. Once this tapered off isolator switched output to trailer batts and had 14 amps to the trailer batteries. Refrig was off and with the trailer closed up there is no way to measure the voltage at the batteries. Another minor mod in the works maybe.
Remote breaker box at the camper
Under hood breaker box and battery isolator
