Tow Vehicle Battery and Alternator
My trucks alternator is rated at 150 amps. Its starting battery is your typical 600 CCA AC Delco variety. My goal is to increase charging capability through the 7 pin pigtail connector near the hi...
Forum Discussion
landyacht318 wrote:
I'd run dedicated wiring so at least your trailer battery gets nearly the same voltage as the engine battery.
The voltage your engine battery gets is decided by the vehicle's voltage regulator, and none of these are programmed intending to quickly and fully recharge depleted batteries.
Mostly they are designed to never overcharge, and as such, will drop to mid to high 13's relatively quickly, but all vehicles will vary in the max voltage and for how long it is held.
Only if your alternator was incapable of meeting all the loads applied to it would increasing its rating prove beneficial, and likely only at higher rpm, not idling.
Likewise a larger better starting battery is not going to assist trailer battery charging.
I'd get the following 6awg harness or similar, and run it to alternator + and a - mounting bolt. Disconnect the connector manually when parked for any length of time so trailer cannot discharge engine starter battery.
Thanks for the response. 2 follow up questions. If my DC to DC charger is rated at 40 amps (Renogy has one), would it be a bit taxing on the 150 amp OEM alternator? Any benefit to upgrading to a 220 amp alternator in this case?
Secondly, do these dc to DC chargers act just like a conventional onboard RV multiphase converter? Bulk to absorption to float? From my understanding, with this setup, I would rarely get above 80% stage of charge after a 3 hour drive, right?
