12V to power winch

[CappyHamper]

Hi all, we're on our 2nd PUP but first with a "crankless" roof. Yes it's loud but I don't like to crank Question...if our PUP battery dies while dry camping, is it safe to plug the harness back into our TV, start the engine and power down the roof? My theory is that the 12V PUP system is actually running off the TV (and at same time is trickle-charging the dead battery), so there's full amperage to the winch. Any thoughts on this?

[3hooligans]

Might be easier to use jumper cables battery to battery.


Me the missus and three hooligans!
2014 Rockwood Premier 2317g
2012 Ford F150 super crew ecoboost
2011 Honda Pilot

[gruss01]

Jumper cables would probably save you a headache, if the battery is pretty low, when you start the truck it's going to draw A LOT of amps...probably more than most (all?) charge lines are designed for and maybe blow the fuse. If it's really dead might draw enough to melt something before the fuse blows.

[f5moab]

Not sure of the amp draw, but I don't believe it is that high. When adjusting the limit switches on my power winch a month or two ago, I used a jump box and raised and lowered the roof at least a half dozen times till I got the switches set correctly. According to gauge on the box, it didn't drain it by much.

But good jumper cables would be a very safe bet.

Or a power drill....

[gruss01]

The winch itself isn't going to hurt the charge line, but if the battery is dead like he mentioned when he plugs in...that can be bad on little wires, worse if the TV is running before he plugs in unless you like pretty sparks.

Going down I don't think the winch draws much at all, but if the battery is so dead it won't even do that it's pretty dead is the assumption I was making, so I"d be careful plugging into the TV

[f5moab]

Would you be plugging in the trailer plug while operating the winch?

[gruss01]

Me? no. What I'm saying is take a flat battery then hook it up to run it in parallel to a standard fully charged 600 CCA or so auto battery and measure the amperage when they try to equalize....I don't know the amperage but a battery is capable of delivering more then enough to melt 10 gauge wire.

Safer to get some charge back in that camper battery first if it's really that low before relying on the 7 pin to run the winch is all I'm saying

[rsdata]

using TV harness to power the winch assumes the 7 way plug wires are even wired to do a battery charge on the camper...

I agree that an emergency jumper box or jumper cables to the TV would be the safe bet

[CappyHamper]

Thanks, you're right, I've always carried jumper cables since I grew up pre-cell phone . And no one should plug in to their TV while its engine is running. But I'm confused about a PUP's power circuit. I thought the 7-way plug supplied power to the converter box--when being towed, converter box doesn't really convert anything it just sends TV power to energize the 12V system running lights (wait, it does send a 2v or so trickle charge to the battery).

Anyway, if winch is powered by the 12V system (and not straight from battery), winch's draw is always thru converter box regardless of where its power's coming from (shore power, TV or battery). Now logic tells me if the battery's dead, I could power up the converter box/12v circuit by either TV or shore. Winch's power draw goes thru the same wiring and fuses any which way, and no component's ever smelled funny or blown no matter which way I've powered the converter box. Weird things happen with electricity though. I've rambled long enuf, thanks for correcting any erroneous thoughts or agreeing or telling me I'm all wet

[gruss01]

TV doesn't supply the converter, it's connected direct to your battery more or less and charges from the vehicles alternator. The winch is also connected direct to your battery, it's probably the fat wire with a big slow blow fuse on it

[f5moab]

I have four hot wires on my setup.

As you can see in the photo, one red wire is from the battery, from and to the converter and to the breakaway brake switch. This circuit goes through a 30A inline fuse; just outside of the photo.

The other red wires are labeled and are the positive to the power winch (with a circuit breaker right at the battery), and the other one goes to the second battery positive cable. The thin black wire is the Trimetric Meter I installed inside the trailer.

It appears when looking under the trailer, the TV hot wire, converter hot wire, battery positive wire and breakaway brake wire are all spliced together.

So when the TV is connected, power is supplied from the TV to the battery and to the converter. The converter will use it for the detectors and for the fridge if switched to the 12 volt mode.

When the TV is disconnected, the battery will supply the 12 volts to the converter to use for whatever is required in the 12 volt circuits of the trailer.

If the trailer disengages from the TV, and the brake breakaway pin is pulled, the batteries supply 12 volts through the switch out to the brakes to, hopefully, stop the trailer.

[CappyHamper]

Well I was sure mistaken! Thanks all so much for the info, that's a big help.