Trailer wiring Q...

[NotMatt]

So I bought a trailer, and I'd like to put a small winch on said trailer for yarding broken rigs and such onto said trailer. My first idea was to simply throw a battery box inside the toolbox on the front tongue, and remember to charge the battery before needing it.

However, that seems like a recipe for leaving me with "dead trailer winch battery" at the times I would most likely use it.

My trailer has a breakaway box, and I just fixed the fused 30-amp key-on 12 volt feed that goes through the 7-pin connector, so now my breakaway box says "charging" whenever I have the truck plugged in and running.

My question... can I put a battery on the trailer and just splice into the charge wire for the breakaway box and have the battery charge from that? Or am I asking for trouble? Do I need a battery isolator? Do I need to upgrade the wiring/circuit for the 12v key-on circuit in order to charge a larger battery? Can I mount the bigger winch battery permanent, and do away with the breakaway battery altogether and just wire the breakaway switch up to the regular battery?

What's the "right" way to do it? I know there's people with enclosed trailers that have batteries and such... how do you keep those charged?

Gimme some thoughts here ya'll.

 

[hlb3]

You could just grab a solar charging panel and mount on the box to keep it charged up, I remember they did that on Xtreme 4x4 (I think) a few years ago.

Other than that, I would personally just ditch the break away battery and power it off the winch battery.

 

[NotMatt]

You could just grab a solar charging panel and mount on the box to keep it charged up, I remember they did that on Xtreme 4x4 (I think) a few years ago.

Other than that, I would personally just ditch the break away battery and power it off the winch battery.

A solar panel mounted anywhere on my trailer would just end up getting broken or stolen, lol. If I had a camper or enclosed trailer, I'd be all over that idea, mounted right on the roof, but for just running a winch occasionally the investment doesn't seem worth it.

 

[leadfoot067]

i just ran the charge wire to the battery while leaving the breakaway box hooked up..a friend of mine got a 400 dollar ticket for not having alll the proper stuff on his trailer.

 

[ain'tstuckjustresting]

You need to isolate the battery or when it gets low and you use the winch it will try to pull all the amperage through your charge wire and blow the fuse. We had a lot of issues with our dump trailer doing that. I just use a simple 30a relay that is closed by the tail light circuit. Any time the lights are on the battery is charging off the hot wire. lights off the battery is on it's own.

 

[NotMatt]

You need to isolate the battery or when it gets low and you use the winch it will try to pull all the amperage through your charge wire and blow the fuse. We had a lot of issues with our dump trailer doing that. I just use a simple 30a relay that is closed by the tail light circuit. Any time the lights are on the battery is charging off the hot wire. lights off the battery is on it's own.

Makes sense. I suppose i could just wire up a switch inside the toolbox. Leave it on normally, cut it off before using the winch to avoid popping the fuse. I will wire it up and see how it works. I predict it may pop the fuse anyway trying to recover a deeply discharged battery with that small gauge low amp circuit. That or it just won't fully charge.

 

[ain'tstuckjustresting]

On the dump trailer I wired it so the charge relay is normally closed then when you push either up or down it opens. Always keeps it charged even w/ 2 deep cycle batteries. I remembered it was the horse trailer I wired to the tail lights since I always towed w/ the lights on.

 

[ain'tstuckjustresting]

Oh, and not sure what your rig is but on super dutys the charge wire is key on so if you shut it off there isn't an issue anyway.

 

[NotMatt]

Oh, and not sure what your rig is but on super dutys the charge wire is key on so if you shut it off there isn't an issue anyway.

Oh you're right, didn't even think of that. My truck is a super duty. I think I'd probably still put some kind of fuse on the charge wire right at the battery on the trailer though, in case I let a friend borrow the trailer and their circuit isn't protected or set up to be key-on only. My thought is that a fuse should protect that accessory circuit too, if the winch draws the battery down far enough and tries to pull through the 12v accessory circuit, it will pop the fuse and that'll be that.

 

[zukkev]

It'd be much simpler and safer to wire in a relay to separate the two (truck from trailer) in the event the trailer is borrowed like you said...:awesomework:

 

[NotMatt]

On the dump trailer I wired it so the charge relay is normally closed then when you push either up or down it opens. Always keeps it charged even w/ 2 deep cycle batteries. I remembered it was the horse trailer I wired to the tail lights since I always towed w/ the lights on.

I like this idea. I could wire it up so it's always charging, and the relay opens and breaks the circuit whenever the winch is powered in or out. Just have to get a relay and a couple of diodes for the in/out triggers on the winch solenoids.

:awesomework: