RustyJC wrote:
Dayle1 wrote:
Any trailer with a residential refer should have a dedicated 12v system isolated from the primary battery or a shutoff circuit to prevent draining the primary battery.
Why? The +12VDC wire (pin #4 in the Pollak connector) has no problem keeping the trailer's battery bank charged while we're on the road. If I were running with no +12VDC feed from the truck as some suggest, then that could be a problem insofar as the breakaway system is concerned, but as I've said repeatedly, I would never run without the +12VDC feed being connected. It's there for an important, valid, safety-related reason.
Rusty
How do you overnight w/o shore power and still KNOW you have sufficient battery power for the break-away circuit the next morning?
I agree, the important, valid, safety-related reason is power for the break-away circuit to operate the trailer brakes. Last time I looked at the DOT regulations for commercial cargo trailers, they were required to have a dedicated battery for the brakes, nothing else could be connected to that battery (interior lights or other 12V items must be powered via the tow vehicle harness). The circuit also includes an LED light that shows when the brakes have been activated. An LEO could pull the break-away pin and the light needs to stay on for minimum of 15 minutes. Failure could result in a ticket.
