Running trailer from tow vehicle inverter

boosTT wrote:
Why not just use jumper cables from the truck battery to the trailer battery?

SoundGuy wrote:
The truck's voltage regulator will limit voltage to well below what is necessary for a correct bulk charge - 14.4 to 14.8 volts, depending on the battery. This is where a DC > DC charger shines as it avoids this issue and will allow the trailer battery to bulk charge properly.

westend wrote:
That may not be accurate. A user would have to measure voltage/amperage with both batteries connected.

It is accurate ... voltage may initially be acceptable but will drop quickly, well below what is required for proper bulk charging. If were as easy as connecting jumper cables to recharge a trailer battery using the tow vehicle we'd all be doing it. There would also be no need for DC > DC chargers which avoid this issue entirely.

westend wrote:
It may be that using jumper cables pushes more amps into the depleted battery than the daisy chain of inverter->converter-> depleted battery. I know if I wanted to use my truck as a charging source for depleted batteries, I'd use jumper cables. I wouldn't expect to put a full charge into the battery, merely sufficient charge to power up necessary devices on an emergency basis.

I have a set of 4 gauge charging cables as well, not for recharging but to load support the trailer battery when it's under heavy load from the inverter. Works well for this purpose but not for restoring a depleted trailer battery.