Forum Discussion
pianotuna
Dec 21, 2020Nomad III
StirCrazy wrote:theoldwizard1 wrote:
Sometime around 2000, the entire auto industry switched to "smart charging". Smart charging is when the PCM controls the output voltage to the alternator to limit the voltage to "just enough" to replenish the battery after a start and not left the voltage go so low as to discharge the starting battery.
This means that about 5-10 minutes after starting you vehicle the output of the alternator is about 13.2V-13.4V and there is not much you can do about that !
USING HUGE WIRING FROM THE VEHICLE BATTERY TO THE RV BATTERY DOES NOT SOLVE THIS PROBLEM !
The only solution is a DC-DC battery charger mounted close to the RV battery. Most can accept voltages as low as 10V-11V and boost them up to the proper voltage (>14V) to charge a battery.
if your rv batteries are down this should put a load on the system that the PCM will see and it should increase the output accordingly which would mean the larger size wire should work.
Steve
Hi Steve,
No. Even with wire intended to carry 80 amps, I do not get "more charging" from the alternator--unless I put a 150 amp load on the house batteries. As soon as I remove the load charging goes back to being minimal.
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