How do I wire trailer winch/battery to truck batteries?

[ChrisKringle]

I have 10000lb winch on the front of my 16' flatbed trailer for getting my broken jeep on or pulling off a load of debris (pulley welded to rear, and small sled at front) off. I currently have a full size auto battery on the front of the trailer that will run the winch throughout the day, then trickle charge it at night.



Now, here's what I want to do and bought parts for today. Run a heavy gauge (friend got me 1/0) cable from the batteries positive lead all the way back to the bumper where I will drill it for a flush mount female welding cable recepticle, then on the trailer have a similar heavy gauge cable run from the positive of the trailer battery/winch to a male welding twist lock connector that will twist into the aformentioned flush mount female recepticle. The reason for this is so I can have 3 batteries in parallel for all the current I will need, plus the trailer battery will charge when the vehicle is running. Oh, forgot to mention the 200 amp mechanical inline relay that will only allow the trailer battery to be connected when the vehicle is running.



Everything sounds good to me, but here is my question: What about ground? I was thinking about connecting a heavy ground strap from the battery negative to the trailer frame, and just let the current run throught the trailer tongue/ball intersection and ballmount/truck receiver intersection. The ball/coupler union of the truck/trailer looks clean, no dirt, and I dont use grease, I dont see how this could not work, will it? I use the aluminum adjustable dual ball mount. It will save me running another ground cable from the truck frame to the trailer frame via welding cable and quick twist connect.

 

[SWiller]

I would not run that kind of amperage through the trailer connection, I use these and you can run jumper cables too.



Replacement Plug Ends - Set of Two - Superior Signals



hope this helps

 

[Hoefler]

You would need the same size ground cable to the batteries. If not, you would be relying on the 10 ga wire in the plug and the connection at the ball. You could burn the ground wire out. I would use a deep cycle battery on the trailer, it is designed for this type of load and draw, a cranking battery is not. Then attach the hot and ground wire in the plug to your battery. The battery will charge while the truck is running. This is the way I have run a hydraulic dump trailer and a race car trailer for years.

 

[CKelley1]

run a second wire from the battery swap the connectors so that you do not connect up backwards and add a fuse link to the truck battery. you will be impressed of how much damage a pinched 1/0 cable can do

 

[ChrisKringle]

Good advice thanks, guess I will run a ground strap from the frame of the truck to the trailer battery/winch so I don't get high current through the 7blade round trailer plug. Someone said to use a forklift plug for the connector and that looks alot less bulky than welding plugs.



I also read somewhere where a guy uses a 16"x16" solar panal to trickle it all day long, and he says he hasn't had to touch the battery in over 3 years, that's using a winch too.

 

[DKnotts]

Don't know how well a solar panel that size would work, depends on the amount of sun and how much winching you do in between sun charging cycles. But I feel that's a different issue if you really want to get into it.
As far as your ground issue-I would absolutely use a second same gauge wire as ground all the way from the trailer batt to your truck batt hook up point! Do not rely on the 7-pin or ball/factory truck ground straps to handle anywhere near 200A! In essence the way you intend on using the trailer batt it needs to be set up similar to your truck batts. -heavy gauge wires run directly between each batt. , both positive and negitive. And CKelley1 was right on with adding a second 200A fuse inline on the truck where the positive trailer batt wire hooks in. There are cheap versions available at places like pepboys that work just fine. I have something similar to your idea in place but only 150A in my setup. I personally feel a fork truck plug set is the easy way to go and is what I use but use what you feel looks and works best as long as it's rated higher than your fuse rating.
If your interested in my setup I'd be glad to share more details.

 

[ChrisKringle]

Don't know how well a solar panel that size would work, depends on the amount of sun and how much winching you do in between sun charging cycles. But I feel that's a different issue if you really want to get into it.

As far as your ground issue-I would absolutely use a second same gauge wire as ground all the way from the trailer batt to your truck batt hook up point! Do not rely on the 7-pin or ball/factory truck ground straps to handle anywhere near 200A! In essence the way you intend on using the trailer batt it needs to be set up similar to your truck batts. -heavy gauge wires run directly between each batt. , both positive and negitive. And CKelley1 was right on with adding a second 200A fuse inline on the truck where the positive trailer batt wire hooks in. There are cheap versions available at places like pepboys that work just fine. I have something similar to your idea in place but only 150A in my setup. I personally feel a fork truck plug set is the easy way to go and is what I use but use what you feel looks and works best as long as it's rated higher than your fuse rating.

If your interested in my setup I'd be glad to share more details.

Good advice, thanks, yeah using logic I sumised I would have to run a cable of same dia. for negative as well. What if I ran the same gauge from truck neg. to frame, then from frame to forklift plug. That would save me $, or is it just best to run straight cable? I will also make sure to use a 200 amp fuse on the positive.

 

[K5IP]

Chris,

If you can run a frame to frame connection, capaple of handiling the current, (200A) that should be all you need. The frames of both vehicles can handle the current without any problems.

The frame to frame connection is the only problem and it may be hard to find.

Also, the connection does not have to be the same size as the positive (welding) wire. A smaller size wire will still accomidate higher current but with a slightly higher voltage drop (loss).

Even so, if the length of the connection is small, the difference in performance will not be significant.

Rog

 

[jelag]

We have several trailers that have a hydraulic system that is battery powered... We've gotten a plug from WW Grainger or a local fork lift truck supplier and have installed a electric forklift plug on each truck and each trailer... we've run a 00 wire from the postive term of the battery and a cable to the frame of the truck...



On the trailer the same plug runs to the battery... . We use this connection to charge the trailer battery and to supply power to the system as well as add additional power to the hydralic system...

 

[steved]

A 200 amp relay won't be enough... a true 10k winch will draw upwards of 500 amps.

I would look at one of the winch suppliers for their remote mounts, and buy their wiring kit. I have one on my truck to run a Ramsey ProPlus 9000 from the rear receiver.

A 10k winch is a lot of winch... and a lot of draw.

 

[ChrisKringle]

Now that I look at manufacureres specs, you are right! So, does that mean I just run straight 1/0 cable from the positive battery to the trailer (with quick disconnect of course) cause no fuse/relay is not rated that high?

 

[steved]

Although not ideal, that's how I have mine ran. Ideally, I should have a shut off switch, to prevent a direct short should the wires wear through.

 

[K5IP]

Chris,

I still think you are OK with the 200A relay. Keep in mind that a relay designed to switch 200A can carry much more than that in a continuous mode.

Also, remember that much, even most of the peak current your winch demands will be provided by the trailer battery. This is due to the fact that there is a small voltage drop (under high load even with the welding cable) between the truck and trailer which will reduce the current from the truck. .



I think you have done a fine job with the welding cable for the positive run, and remember, even the starter in our trucks, (500 to 800A) uses the frame for a negative return. Using a frame negative return should not be a problem as long as you can provide a high current negative connection to bypass the hitch

Do however fuse this thing. (A fusable link might be in order). Should a short in the wiring back to the trailer occur, the very low resistance of the welding cable could cause a battery explosion.

I've seen it happen--not pretty.



One other very nice feature of your design is that the low resistance of the welding cable will allow a very complete/quick charge from the truck alternator (low voltage drop).

Way to go!

Rog

 

[ChrisKringle]

Chris,

I still think you are OK with the 200A relay. Keep in mind that a relay designed to switch 200A can carry much more than that in a continuous mode.

Also, remember that much, even most of the peak current your winch demands will be provided by the trailer battery. This is due to the fact that there is a small voltage drop (under high load even with the welding cable) between the truck and trailer which will reduce the current from the truck. .



I think you have done a fine job with the welding cable for the positive run, and remember, even the starter in our trucks, (500 to 800A) uses the frame for a negative return. Using a frame negative return should not be a problem as long as you can provide a high current negative connection to bypass the hitch

Do however fuse this thing. (A fusable link might be in order). Should a short in the wiring back to the trailer occur, the very low resistance of the welding cable could cause a battery explosion.

I've seen it happen--not pretty.



One other very nice feature of your design is that the low resistance of the welding cable will allow a very complete/quick charge from the truck alternator (low voltage drop).

Way to go!

Rog

Exactly, high current from the trailer battery, 200 amp relay in positive line, 1/0 cable from positive truck to winch (fork lift plug in between), large cable from truck frame to negative battery/winch/frame of trailer (via fork lift plug again).

 

[MFalkinham]

I'm building a winch setup similar to ChrisKringle for my 18' car trailer and 12' utility trailer. Mine will have a custom-made receiver mount so I can move the winch between my trailers or even use it right from the truck hitch.

The winch setup will have a deep-cycle Optima battery dedicated solely to it, but I want to hook up a trailer plug connection so the truck batteries will charge this winch battery while driving. I would then disconnect the truck batteries during actual winch use. Will this setup work just for battery charging purposes?

 

[K5IP]

MFalkinham,

Charging the Optima through the trailer plug will limit the battery charge rate due to the small size trailer plug wiring in our trucks.

Some of us improve on this set up by adding a heavier wire from the truck battery to the trailer plug connector.

It should not be necessary to disconnect from the truck batteries when using the winch unless you are worried about depleting the truck batteries to the "no start" condition.

Rog

 

[cksh8me]

I'd use your standard trailer connection plug to charge the battery.



Just like all the 5ers going down the road.



Yes you won't get as much of a charge as quickly but it will plug into any other pickup if you have to pull your trailer with somebody elses rig. (When my dads truck puked a transmission and we put the truck on his trailer we all laughed. "I bet that truck never thought it would be on that trailer")it happens. Install an isolater between the plug and the trailer to protect you from discharging the truck batteries. If it works as is and you trickle charge it you are good to go with this setup. And it's a standard deal.

 

[BDaugherty]

I agree that for that type of amp draw, you must run both pos and neg cables straight from the battery, through a connector of your choice, and to the winch. Do not use a fuse of any sort. Just be very careful with the routing of the pos cable. An old garden hose cut up and slid over the cable will protect it from chafing and pinch points.

I'm running a Warn HS9500 on a multi-mount cradle. With front and rear receivers, I can put it where I need it. Also, with my gooseneck trailer, the winch mounted on the rear works beautifully for dragging crap onto the trailer deck. I'm running 0 gauge pos and neg cables straight from the battery through quick connectors to the winch. I haven't made any really tough pulls with it, but so far the performance has been very good and the utility is awesome.

I've got a 8000lb Ramsey that I was planning to mount on my trailer. When I came across all the multi-mount parts at a great deal, it took the pressure off to mount the 8K winch.

 

[SSolderitch]

maybe overkill? I have only a 5000 ramsey winch mounted on the trailer with a full size battery, recharge thru the oem 7 pin connector and never had a problem. Have all kinds of lights for night time loading. Loaned the trailer out with a truck without a charging wire in the plug, and still had no problems with the battery running out of juice even with a few "winch & lights cycles". It may be cheaper to add a second battery to the trailer and let the truck charge them when driving.