rickst29 wrote:
"Will my Tow Vehicle (unmodified) re-charge the Trailer batteries while towing, in less than 6-8 hours?"
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The answer is NO, and upgrading to a slightly bigger "Trailer Battery Charge" wire will not help this by much. A massive wire upgrade is required.
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AMAZING ! I have written most of the same things you said about recharging TM batteries several times on this board and they have been ignored !
rickst29 wrote:
In the Tow Vehicle, the actual voltage of "+12VDC" is determined by a regulator - typically integrated into the Alternator or an Engine Control Module ("ECM").
In a previous life, I was an automotive engineer working for one of the Detroit 3 for over 30 years. For over 10 (15?) years, all US light duty vehicles have used the ECM/PCM to control the alternator output voltage. Again you are correct, under normal operating conditions, it is less than 13.5V !
rickst29 wrote:
If you use a really heavy cable, direct to the Trailer batteries form your TV battery, then you can charge them effectively ...
Maybe. What is "heavy" enough ? #8, #2,#00? Even then, you are still NOT going to get the proper multi-stage charge on a deep cycle battery that is 50% discharged so that you can "comfortably" boondock that evening !
rickst29 wrote:
The "fixes"
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The most effective fixes raise the TV Voltage in various ways, and run a higher-Voltage Bargeman (or Auxiliary) power wire into a Solar Controller, or into the Converter as 120VAC input:
#1: Buy a purpose-built Redarc or Ctek, which Boosts "Tow Vehicle Voltage" after it is received in the TM.
The CTEK D250S requires a MINIMUM of 12.9V to operate. That is pretty close to the voltage available after voltage drops.
rickst29 wrote:
#2: Create a new "Charge from TV" method (using a 120VAC cable connnected to Converter AC input) fed by a 120VAC "Inverter" inside the TV. This is fairly cheap, but requires another cable between TV and TM at the hitch, and running all the way back to the Converter.
While maybe not the SAFEST solution, this probably the BEST, especially if you have a GOOD converter charger !
(make sure you have a "breakaway" connection between the TV and TM.)
