What size winch (electrical) cable?

[isuzurover]

90/110/130 owners only please - with under-seat batteries.

(A) What size ELECTRICAL cable do you have between your winch and batteries?
( B ) How many HP is the winch motor?
(C) How long is the cable run (looks like it will be 2.8-3.2m on mine...?
(D) has anyone wired their winch via their starter (at least on an ISUZU, the direct line between the battery and the winch runs right past the starter)?

[Psimpson7]

90/110/130 owners only please - with under-seat batteries.

(A) What size ELECTRICAL cable do you have between your winch and batteries?
( B ) How many HP is the winch motor?
(C) How long is the cable run (looks like it will be 2.8-3.2m on mine...?
(D) has anyone wired their winch via their starter (at least on an ISUZU, the direct line between the battery and the winch runs right past the starter)?

A: 70mm2 decent quality welding cable
B: 4.6hp Front / 6hp rear
C: Through the LH chassis rails to front and back so the shortest posible going that way. Probably each are about 3m as you suggest. The relays are as close to the motors as I can get them.
D: Not any more. Mine are wired directly to my 2 batteries, although both are independently isolated with 500amp continuos isolators and also both run through 500amp mega fuses. When I got mine it had a LR supplied Warn xd9000 as a dealer fit option and that was wired to the starter motor from memory

[isuzurover]

Thanks.

By my calcs...
6HP winch motor = 447 A max assuming 80% motor efficiency (which is reasonable I think?).

Without pulling out my textbooks - I found this calculator, which seems to give good results:
DC cable sizing calculator - Energy Matters

For 447 A and 3 m cable run, it tells me I need ~100 mm2.

Now of course the winch will rarely (if ever) get to the full 6HP load, however I like to overengineer things just in case...

Anyone see any problems with this?

[Psimpson7]

The only real issue I can see is that the bending radius of a 100mm2 cable is going to be quite open, that and the fact that all the terminals and so on will be massive. I also think that it is probably overkill. Even 70mm is basically twice what they are supplied with.

[101 Ron]

I have been running my winch from the starter with the cable supplied with the winch with no problems...........DC TDI 130

[scott oz]

My winch before I took it off for diff locks was wired directly to the starter motor.

I was going to rewire to the battery but the auto electric bloke was most instant that it is most effective and should be wired to the starter.

[Vern]

100m2 cable would be if you were running your winch continuosly, therefore cable would not get hot. I think even 70mm2 would be overkill.

[Bundalene]

Also check the size of the ground cable on the Defender, the one which goes from the battery to the chassis / T/X box.

On the winch on both our Defender and D2 Disco I used 70 sq mm cable for both the Active and Ground. I wired the ground back to where the battery cable was connected to the chassis and the active back to the battery.

In the Series2 Disco the main earth cable is about 50sq mm and in the Series1Disco it is even less - probably 35sq mm, but these are very short runs and voltage drop would be small.

Erich

[Toxic_Avenger]

Epic thread dig, but if the info is here, why not expand on it...

I have been recently pondering this very conundrum.
I have access to welding cable of all sizes and suitable lugs/crimping tool.

CIGweld advise a ISO 70mm^2 cable is rated at 355A @ 100% duty cycle.
Compared to 50mm^2 cable at 285A @ 100% duty cycle.

Welding cable can sure handle the heat, current and is much more flexible than normal cable due to the high strand count in the wire.

Does anyone have any long term / recent experience in their own winch electrical cable selection? My wallet says 50mm2 would be fine, calculations suggest larger.

FYI, my winch is an XDC 9500lb model, it's rated at 358A at full load.

I can effectively halve the conductor length by earthing the winch negative to the chassis somewhere, but not sure if this is best practice?

[100inch]

50mm2 welding cable for normal use (Husky10 and Warn 6hp), but having +&- both straight from the batteries to the winch solenoid. 70mm2 for comps(6hp x2). There is high flexible welding cable available which makes it very easy to bend around bulkhead and chassis but I found it very hard to achieve bulletproof crimps so I stopped using it. m