Bert the Welder wrote:
Thanks. I'll look him up and try to find the vid's. It certainly seems like having something like the DC2DC is needed for the "new" type batt's.
First, I worked for Ford designing Powertrain Control Systems for over 30 years until 2007, so I DO KNOW what I am talking about. Yes, I am sure things have changed since then and different manufacturers do things a bit different.
Second,
there are really two issues here. Is the alternator capable of putting out sufficient voltage and current to charge a RV "house battery bank"
(1 or more batteries wired for 12V nominal) AND are voltages directly from the alternator "optimal" for recharging a house battery bank.
Almost all vehicles built after about 2000 have some type of "smart charging" system. Theses systems are designed to only replace the amount of energy used to start the vehicle and not let addition loads cause the starting battery to discharge. In simple terms, immediately after starting, the voltage at the starting battery will be about 14V. Within about 5-10 minutes, that voltage will drop done to about 13.2V at the starting battery. Even with the heaviest gauge wire you can install,
you are not going to get more than about 13.2V at your house battery bank ! This is not sufficient to recharge a house bank that is below 80% SOC !!Different battery chemistries require different voltages for optimal and complete charging. Flooded lead acid is different than AGM is different than LiFePO4.
A DC to DC charger, install close to your RV's battery bank, will BOOST the incoming voltage and apply the correct voltage to your battery bank !
