theoldwizard1 wrote:
Read this regarding charging a house battery from a vehicle alternator.
DC-DC battery charging
Get rid of the relay and replace it with a CTEK D250SA
There is (at least often) a significant practical difference in the battery isolator circuitry on a motorhome and the house battery charging via the 7 pin connector for a trailer. On a motorhome, the batteries are physically closer together and connected by much heavier connections, so the charging of the house battery via the engine alternator is significantly better.
I have actually observed over 50A of house battery charge current on my class C. If memory serves, the wires are fused at 175A. The voltage drop is fairly minimal, and the house battery can get fully charged (or at least close enough to that for practical purposes) just as well as the chassis battery can. The CTEK unit, with its 20A limit, would be an expensive downgrade on the whole.
