eb145 wrote:
This device definitely increases the amps going into the battery. something like 2 Amps without it, and up to 20 Amps with it (till truck fuse blows). It does this by raising the voltage closer to the battery terminal. Your idea of boosting to 72 volts for the long distance run on the existing truck wire and then dropping to 14+ volts is very interesting. Increasing the voltage by a factor of 5 or 6 will reduce the current by a factor of 5 or 6.
300W/72V = 4.2 Amps on the truck wire which is way under the 15 Amp limit for 14 gauge wire.
Ed
Ed, I'm impressed with what you've done as I've been messing around with a similar concept, mounted as close to the trailer battery as possible.
A couple of what-if questions.
Ebay sells a $25 version of that DC-DC booster that is rated at 400 watts and has potentiometers that allow you to adjust both maximum voltage and current. What if you used one of these instead?
http://www.ebay.com/itm/111177068259Second, why couldn't one use a solar panel controller in series with the battery to regulate the battery charge rate? You can pick up a charge controller for $15 that will measure the battery state of charge and regulate the input voltage to keep from overcharging it.
http://www.ebay.com/itm/12V-24V-5-10-15-20-30A-PWM-Solar-Panel-Battery-Regulator-Charge-Controller-/351004581852?pt=LH_DefaultDomain_0&var=&hash=item51b980dfdc
