Specularius wrote:
I personally think you are just creating a parasitic load that adds nothing to your batteries. If you measure the actual current going into the batteries, I bet you find it higher without your device. Having said that, if you were to put a dc-dc switching power supply at the front of the truck and upped it to 72 volts and then another one at the rv to drop it back to 14+ volts, then you have done something.
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
