Brian,
Prior to your purchase of the isolator, you might want to check out the solid state isolator by Hellroaring technologies (
www.hellroaring.com). I am new to the world of battery isolators but I understand from a review of isolators that both diode based isolators and relays have disadvantages compared to the new solid state type offered by Hellroaring (
http://www.off-road.com/chevy/reviews/hellroaring/). The biggest disadvantage of the diode based isolator appears to be voltage drop of about 0.8v. That could reduce the capacity for battery charging. Hellroaring Technologies battery isolators/combiners can be mounted on the camper (
http://www.hellroaring.com/rv.htm) without altering the tow vehicle's wiring. I plan to look into their 75150 isolator for mounting on our Trailmanor. The cost is ~$125, but I could switch tow vehicles and still have isolation. Plus the wiring appears to be simpler.
Also, the wiring on our 3124 Trail manor the "hot" wire from the vehicle goes to the back of the trailer (with 10 ga wire, I presume to the converter) and then returns via 12 ga wire to the battery. I wonder if it would improve battery charging to have shorter circuit in series which would bypass the converter and go directly to the battery?
Any thoughts/suggestions would be welcome!