Direct Charge Circuit
I would like to run a direct line from my truck alternator to the house batteries in my fifth wheel trailer. Has anyone done this project that could offer some suggestions on how to and what materials...
Forum Discussion
Sal's suggestion for situations where there's a long wire run between the alternator and the batteries to be charged is indeed the best way to do it.
Otherwise, as others have said, the largest practical wire size should be used between the engine battery or alternator and the RV batteries for direct connection together of all of them.
However just for information purposes, perhaps our Ford alternator setup is a bit different: When our RV batteries are way down, the alternator will provide 20-30 amps into the RV batteries over 6-8 feet of 6 gauge cables for several hours while driving. It may be that the 200 amp hours of discharged RV batteries reduces the overall voltage of the three batteries in parallel enough such that the alternator merely is sensing that a "large engine battery" is heavily discharged and hence needs this level of charging current.
Otherwise, as others have said, the largest practical wire size should be used between the engine battery or alternator and the RV batteries for direct connection together of all of them.
However just for information purposes, perhaps our Ford alternator setup is a bit different: When our RV batteries are way down, the alternator will provide 20-30 amps into the RV batteries over 6-8 feet of 6 gauge cables for several hours while driving. It may be that the 200 amp hours of discharged RV batteries reduces the overall voltage of the three batteries in parallel enough such that the alternator merely is sensing that a "large engine battery" is heavily discharged and hence needs this level of charging current.
