Fusing a winch

[BurbanAZ]

I had to extend the cables today for my winch so I can mount the control box where I want and I was wondering does anyone fuse winch? There is a ton of power running through and the solenoid boxes are a tight fit but I've never heard of anyone putting an inline fuse on one.

I've had winches on a few vehicles and never had an issue but it seems like if it did go wrong it would burn ur vehicle down in no time.

I'm guessing the amp draw might be one of the issues in finding a fuse big enough.

 

[eggman918]

I went this route 300 amp battery disconnect switch.

http://www.summitracing.com/parts/mor-74102/overview/

 

[geordie4x4]

After seeing a vehicle burn to the ground because of a short in a winch solenoid, I fitted fuses and kill switches to both my batteries that connect to the winch.

It may be a rare event but it was pretty frightening trying to put out a burning vehicle (unsuccessfully).

I have fitted new battery positive terminals that each house a main fuse link and also have two additional smaller fuses 30A and 50 A (or what ever size you need) for power to other accessories. This way the fuse is at the battery and there is no section of cable hat could present a risk of a dead short in an accident.

I am not sure if this brand is available in the US. http://www.projecta.com.au/Products/BatteryConsumables/DistributionTerminals.aspx#

I use one of these Projecta BT950 terminals on each of my main starting and winching batteries, then a heavy duty boat battery master switch (350A) on each so I can connect one or both batterys to the winch for heavy work. The main black fuse on the fuse box is rated to 150A continuous and 800A maxum. It is also protecting my starter motor and charging cables.

http://www.projecta.com.au/Products/FusedBatteryDistributionTerminal.aspx?print=true

Winch solenoid in waterproof electrical box behind the gril

 

[DaveInDenver]

Know that fusing a winch might mean that they'll open when you're operating it. A Warn M8000 can draw as much as 400 amps at max load.

So you need to size it to tolerate your winch's max current for whatever length of time you think you'll need it to. You figure out the right type, fast acting or time delay, and rated value from their curves. A fast blow type might be specified to open at 150% of rated value in 300 seconds, so you'd have to select something in the 250A to 350A range for it not to open routinely on long pulls, for example. Hard to think you'd need to run your winch at max current for more than 5 minutes but still you need to consider that there's a tolerance to the current and time ratings.

This type of fuse might open at 10x rated value within 1/10th of a second and along the curve it will give you typical operation, so an over current of 5x might cause it to open at 1 second, etc. This is where time delay types might be considered. They are design to tolerate a large in rush for a while to accommodate things like motor starting. For a winch this isn't really useful because the draw is sustained for minutes while a motor might take some number of second to start up before settling.

Problem I see with fusing is that the value you select will only really protect against cable shorts and not equipment issues. IOW, a failing solenoid could draw 200A and generate a lot of heat, causing it to become an issue and maybe catch fire without ever opening a fuse sized not to blow under normal operation. So a fuse seems to me to be incomplete protection and in a way false security if it lulls you into infrequent maintenance and inspections.

A disconnect or kill switch like eggman suggests would be a good option, if something does go wrong you pull the plug. So this along with a fuse to protect if a cable is cut or shorted might be the best way.

 

[geordie4x4]

Know that fusing a winch might mean that they'll open when you're operating it. A Warn M8000 can draw as much as 400 amps at max load.

A disconnect or kill switch like eggman suggests would be a good option, if something does go wrong you pull the plug. So this along with a fuse to protect if a cable is cut or shorted might be the best way.

Well explained Dave,
I have also in a round about way, come to the same conclusion having both the slow-blow fuse on each battery and a switch on each battery.
I do usualy run the winch from both batteries at once so have never experienced a fuse problem as it is halving the load on each.

But now I look at it, the switch position on mine being under the hood might be hard to get to if they needed to be turned off in a hurry.

 

[lqdchkn]

Know that fusing a winch might mean that they'll open when you're operating it. A Warn M8000 can draw as much as 400 amps at max load.

So you need to size it to tolerate your winch's max current for whatever length of time you think you'll need it to. You figure out the right type, fast acting or time delay, and rated value from their curves. A fast blow type might be specified to open at 150% of rated value in 300 seconds, so you'd have to select something in the 250A to 350A range for it not to open routinely on long pulls, for example. Hard to think you'd need to run your winch at max current for more than 5 minutes but still you need to consider that there's a tolerance to the current and time ratings.

This type of fuse might open at 10x rated value within 1/10th of a second and along the curve it will give you typical operation, so an over current of 5x might cause it to open at 1 second, etc. This is where time delay types might be considered. They are design to tolerate a large in rush for a while to accommodate things like motor starting. For a winch this isn't really useful because the draw is sustained for minutes while a motor might take some number of second to start up before settling.

Problem I see with fusing is that the value you select will only really protect against cable shorts and not equipment issues. IOW, a failing solenoid could draw 200A and generate a lot of heat, causing it to become an issue and maybe catch fire without ever opening a fuse sized not to blow under normal operation. So a fuse seems to me to be incomplete protection and in a way false security if it lulls you into infrequent maintenance and inspections.

A disconnect or kill switch like eggman suggests would be a good option, if something does go wrong you pull the plug. So this along with a fuse to protect if a cable is cut or shorted might be the best way.

^^^Pretty much this.

Also since you'll have to fuse at such a high amperage just to use the winch normally it's kinda worthless IMO because the short could have lower resistance than the fuse but still a significant amount to damage other things. So you have a 300-400 amp fuse in your winch power cable but what if your short is only pulling 100-200 amps? There will still be a ton of damage. :/

 

[eggman918]

I mounted the switch ~8" from the battery and I only turn the switch on while using the winch when I installed it I was thinking about collisions and the like and that 2/0 cable grounding out. Disconnects at both batteries might be in order a while back the solenoid on the starter locked in the on position and I couldnt hear it over the 4BT and I damn near had a catastrophic situation on my hands as I only noticed it when the smoke started to come it the cab and then it still took me too long to get both batteries unhooked switches would have saved me much anxiety on that day.

 

[Tennmogger]

Some good answers here. One other possibility is adding a disconnect solenoid in the short line between battery and winch. That way no hood opening is required to turn off the power to the winch in case of a failure of any kind.

General opinion over the years has been don't fuse a winch. The fuse can blow just at the wrong time and necessitate fuse replacement, possibly in a very awkward or dangerous time or place.

I used a SPST solenoid of 400Amp continuous rating (military sealed mercury relay) on the only electric winch I use. Another idea is placing a meter current shunt in series too, with an amp meter you can watch from the cab. You will know what your winch is drawing.

Bob

 

[Weasel with a Diesel]

After reading all this very valid points, I'm happy to have choosen the hydraulic winch...

 

[craig333]

I once broke a motor mount which let my starter cable hit the frame. Not fun fumbling for a wrench and hoping the battery doesn't explode on you out in the middle of nowhere. Disconnects are a great idea.

 

[98 SNAKE EATER]

I have a main cutoff switch under the dash that controls power to both winches and Anderson connector for jumper leads using a PAC solenoid mounted under the hood...

The solenoid is rated much higher than my winches will ever draw and when the power is turned on, the interior switches still won't do anything until a bumper mounted key switch is turned for each winch....

Also, the remote plugs don't see any power until both the solenoid and keyed switch is turned on, so I don't have to worry about some punk activating one of the winches using a paper clip

 

[Tennmogger]

Nice setup!

Bob

 

[SGTCap]

subscribed. My winch is mounted but I still need to wire it

 

[Dennx]

I installed a Blue Sea 350amp shut off switch after relocating my Superwinch solenoid into a new project box.

 

[unseenone]

I have a main cutoff switch under the dash that controls power to both winches and Anderson connector for jumper leads using a PAC solenoid mounted under the hood...


The solenoid is rated much higher than my winches will ever draw and when the power is turned on, the interior switches still won't do anything until a bumper mounted key switch is turned for each winch....

<snip>

Also, the remote plugs don't see any power until both the solenoid and keyed switch is turned on, so I don't have to worry about some punk activating one of the winches using a paper clip

I'd love to see more detailed info / pictures on the rear winch and mount, very very cool setup.