Battery on trailer breakaway switch

Kpackpackkelley wrote:
Morning everybody. Could the breakaway battery be wired in the charge system from the trailer with a PD and charge wizard.

However you do it, the breakaway wire (positive wire) goes straight to the battery positive post and is not fused. The battery has to supply the brakes when the 7-pin gets yanked out and also with any fuses blown.

It does not go to the DC fuse panel for the PD converter as a way to get to the battery, since that puts fuses and breakers in the path, a no-no.

You could parallel the little breakaway battery as a way to recharge or maintain it using the PD converter's second set of terminals or just have the trailer's main battery bank as the breakaway battery, but keep that pos wire from the breakaway switch direct to the battery positive post, no fuse.

Lots of things can be done but what are you hoping to gain by adding an additional layer of complication for no apparent benefit.

If you want to keep the separate battery, something like the LSL Trik-L-Start would be just the ticket to do what you want. It's basically a simple DC powered battery charger, and will charge the little battery whenever the converter is running (or solar is charging, if you have solar) and the main house 12V system is over something around 13V. These are most commonly used on motorhomes to keep the chassis battery charged, but it would work just as well on a trailer if you had a separate battery for the breakaway braking system.

(But I also would vote for just having the breakaway system connected to the house battery and getting rid of the little battery as the best solution.)

I concur. Wire the breakaway switch directly to the house battery and eliminate the little battery.

However, in actual answer to your question, yes it can be. However, you need to take precautions to prevent the breakaway battery from being used to power the trailer's lights, water pump, etc whenever the trailer is not plugged into shore power. A battery isolator will do that.

If you have a big battery for the trailer why not wire the breakaway switch to it and eliminate the little battery. That's the way most trailers are wired.