Winch wiring

[Frank mellin]

Have a folkboat that is fitted witj a warrior ninja winch 35spa 12v 1.37kw motor.
Need to rewire but query over gauge of wire to use.needs to be approx 20 ft and I understand that length is a factor in choosing correct gauge.
Any

 

[Tranona]

What are you using the winch for on a boat? From what I see this is a vehicle mounted winch perhaps for pulling a trailer up a slipway powered by the vehicle battery. Length is a factor for determining gauge of wire and depends on the current draw and the total length of the cable from the battery to the motor and back to minimise voltage drop. There is nothing in the specification that says anything about this presumably because the unit is supplied with the correct size cable to connect to the vehicle electrical system.

 

[Bodach na mara]

You would be better posting this query on the PBO pages to get an informed opinion.
I know little about electric winches but I assume that you're talking about a windlass (for anchor handling) rather than a winch for sheets or halyards. My own SL Seawolf windlass is rather lower powered and draws only 20 amps when operating under load. The power is therefore 240 Watts. Yours will draw about 5 times as much current ; over 100 A. The cross section of the supply cables will be substantial and the longer they are the fatter they will need to be. Think in terms of the sort of cable connecting the engine starter to the battery.
Even for my Seawolf which is about 5 metres ahead of the battery position the supply is pair of cables each about 7 metres long and I estimate that cross section is about 100 sq mm. Which looks like overkill when you see them connected to the two skinny wires that come from the windlass motor. They look like only 6 sq mm CSA. But then they are only about 30 cm long.

 

[Frank mellin]

Is used for anchor mostly but also used for stepping mast via A frame and pulley mounted on foredeck.
Am told that draw on no load is 45amps. On full load 200amps.
Operating via pulley gives 2.1 ratio.

 

[Bodach na mara]

These are awfully high currents to deal with and there is a risk of rather high temperatures being developed. Obviously the cable CSA will depend on tolerable voltage drop and as Tranona says the longer the cable then the larger the CSA. An additional consideration is the method of joining the cables. Currents like those often result in dangerous high temperatures at places where there is a "high" localized resistance for example at switch contacts, plugs and sockets. And don't even think of using terminal blocks.

You need better advice than I can give just now.

 

[Tranona]

i am confused. Is this the winch you have? Warrior Ninja 2000lb Winch

If so, I have never seen one on a boat. It is made for mounting on a trailer or on a vehicle like a Land Rover. Windlasses for boats are very different things normally used for the anchor, but many also have a capstan so that they can be used for other things like going up the mast or raising the mast using an A frame. a small boat like a Folkboat usually has light enough anchoring gear to handle manually although a manual windlass would be useful if you do a lot of anchoring. An electric windlass is feasible but a bit of an expensive indulgence that needs a beefy electrical system to run it.

 

[jamie N]

Is used for anchor mostly but also used for stepping mast via A frame and pulley mounted on foredeck.
Am told that draw on no load is 45amps. On full load 200amps.
Operating via pulley gives 2.1 ratio.

The 45A 'no load' isn't going to be right I reckon, and 'full load' is (possibly) the maximum rated A for the winch.
I was somewhat surprised by the 'no load' figure indicated by this Warrior Ninja 2000lb Winch being 12A!, but it is turning an awful lot of gearing I guess?