Running a 12 volt winch on 24?

[oilcan]

Hey, y'all. Long time, no see. (Don't remember my last post, but it's been a while.)

I have a fairly simple question that may or may not have a straight forward answer. I recently got the old M715 legal again, and mounted up a nice/cheap 12v winch. The problem is don't have the dual voltage system up and running, yet. *The electrical system has been reworked a few times over the years.

I've seen ads for some kind of "24v boost" contraption that will make a 12v winch work swimmingly on a regular 12v civilian truck. So now, the question... Can I just rock this winch on my 24v system without worry? FYI, it's the Harbor Freight Badland Apex 12,000. I don't really want to smoke it and hope they'll happily warranty the thing.

[brute4c]

Good to see you oilcan!

Wish I knew the answer for sure...I am thinking it is not a good idea as the draw is going to be substantial...my opinion mind you...hope someone with more knowledge chimes in with something certain!

[jeeper]

I can't give you a "proper" answer but I can say It will probably work for a while. Most likely what will happen is the motor will run faster than it's designed to. The controls on the other hand may not fare well at 24 volts. The motor current should be about half of what it would draw at 12 volts though. You may look at a DC to DC converter to run the solenoid/electronics and allow the winch motor to run straight 24 volts.

[oilcan]

I do have a fairly complete 12v system set up for the truck, but it's not fully installed, yet. And I haven't really beefed the design up for high-amp-draw accessories. I'm going for "the best of both worlds" voltage-wise, because of the XM818 trucks and potential slave starting, and whatnot. Otherwise, I'd probably just go 12v and simplify my life. The thought of running dual batteries for the 24v system AND dual batteries for the 12v system just seems like a lot of gravity to add to a regular old truck.

I have a nifty NewMar buck converter on the shelf, but it's only rated at 40 amps, continuous. (50 peak) Substantial for regular stuff, but not enough for this nonsense! Wasn't planning to use it on this project, but maybe I can add a few relays into the mix to get things to chooch.

Jon... We need to wheel. It's been too long! The National FE in... 2006? The one in Tennessee?

[Kaiserjeeps]

Hey oilcan! I would think you would fry the motor windings. Or the copper wire on the armature. It is probably a smaller gauge than a 24 volt system would be. That would be my first thought. But I could be wrong. Best to give it 12 volts as it was designed. Incentive to get some quality garage time right?

[jeeper]

I was thinking of this wrong. See post number 7 and 10 from tennmogger
#7
This question has come up for use on 24v Unimogs. The answer is...maybe you can run the 12v winch motor on 24 v but seldom will the control relays handle twice the current. At 24 v the 12v motor will draw much more current and turn faster, of course. Lots of older tractor owners run their 6 volt starters on 12v and get by with it for years, but those usually don't have relays (manual switching).

Why not put a 12v battery on the trailer along with the winch. This solves two problems, it gets 12v power close to the winch and eliminates the need to run long cables (with connectors) from the truck battery.

Then trickle charge the 12v battery off the truck system through a 24 to 12v converter.

If usage is short term, the 12v battery might get the job done without connection to the truck, then charge it when you get to shore power.

A short term charge can be done by running the 24v from the truck through a headlight bulb in series, to the 12v battery. Don't leave it like that or the battery will cook eventually.

Bob

and #10

You guys are thinking constant Wattage.

For achieving the same "Wattage", the current at 24v will be half that at 12v. (Watts = volts x amps). You can't make the motor draw less wattage at higher voltage!!

That DC motor is a big honking resistance. As voltage doubles across a resistance, the current doubles.

I = E/R, and R is constant (for all practical calculations) so as E doubles to 24v, I (amps) does too.

If you want to try that winch on 24v, you can put resistors in series with the relay coils to limit the current to the coils. That will make your relay pack survive. The motor will still be a 'maybe' if you load it down.

As for doubling the load capability of the winch, it's mechanical system would not handle twice the load. (If the mechanicals could handle twice the load, the marketing geniuses would have called it a bigger winch. They already stretch the truth.)

Also consider that the Wattage dissipated in the motor, at 24v instead of 12v, will quadruple!! That sucker is going to heat up fast.

Watts = volts x amps, and both volts and amps are doubling (with resistance constant).

Now, in reality, the commutator in the motor cannot transfer all that power as well at much faster speed. The brushes will arc more and heat more, and that will limit current somewhat....for a short time.

Another option is to buy a 24v motor for your winch. You might need one anyway if you hook the 12 v winch to 24 v

Bob

[oilcan]

Hey oilcan! I would think you would fry the motor windings. Or the copper wire on the armature. It is probably a smaller gauge than a 24 volt system would be. That would be my first thought. But I could be wrong. Best to give it 12 volts as it was designed. Incentive to get some quality garage time right?

I think you're right!