Electric Winch - How do I know the Amps ?

[Ecosse120]

I have just installed an electric winch for my lifting keel but I need to extend the length of the cables and would like to install a fuse in the circuit ? I have been through the instructions but it only says that it's 12V not what the ampage is ? Any idea how I can measure this ?

 

[stevebrassett]

Silly question maybe, but surely somewhere it states the power in watts?

 

[Ecosse120]

It says that it is 1 hp if that is any help ??

 

[stevebrassett]

Yep - 1 hp is about 750 watts, which is 62.5 amps. Which is quite a lot. Someone will be along soon to correct anything if I'm wrong.

 

[nimbusgb]

You need some hefty cable, both to carry the amps and prevent voltage drop.

 

[Norman_E]

The answer from Stevebrassett that 1 HP is about 750 watts, therefore about 62.5 amps is correct, but the current on starting may actually be higher. The makers should advise the correct cable size, which will also depend on the distance from the battery bank. (think of heavy duty car jump lead size cables and you will not be far out.) This sort of current is best switched via a relay, so that the relay contacts handle the motor switching load. That way you install the cables from battery to motor via the shortest route, and can run a thinner cable to a convenient position for the switch. The relay can be placed next to the winch. Note that if the winch has a built in relay it will have two terminals to connect the power cables, and two more for the remote switch. If it only has two terminals you should consider fitting a relay.

 

[twisterkai]

As others have said, 1 hp is about 750 watts, which is a fairly common (ish) rating for an electric windlass. I'd suggest having a look at the tech specs from the various windlass manufactures to work out what size fuse/circuit breaker and cable x sectional area - they all tend to give reasonably accurate info.

 

[Phoenix of Hamble]

[ QUOTE ]
(quote from Norman_E) think of heavy duty car jump lead size cables and you will not be far out.

[/ QUOTE ]Yep.... agree with that... mine are huge..... similar to jump leads... and you can hear the engine go under significant load when you fire up the windlass.....

 

[William_H]

The advice on current carrying cable is good and you can't go wrong with heavy cable and relays which then enables you to have a large current fuse.
However I note this is not an anchor winch but a keel winch.
So depending on whether it is vertically lifting like mine (greater laods)or a swing keel there is not so much effort required. With a mechanical advantage the load will be small so current low while without the mechanical advantage the keel will come up real quick buit with larger current.
A little experience will tell you how much battery power you will need. certainly nothing like you need to haul up 100 metres of heavy chain and anchor. good luck olewill PS I did a spiel on this forum a few days back about anchor winch relay connection which may be usefull.

 

[robind]

If fitting a fuse consider fitting a double version of circuit breakers with a lock out bar so that only one can be used at a time. you probably will never need it but who knows just when you are entering a nice shallow cove the fuse blows and you have to change your plans, with the switch over arrangement you just flick over the bar, flick the switch and try again. obviously if its a motor fault then it doesn`t help but more probably it could just be a tired fuse or circuit breaker.

 

[pappaecho]

If you want to buy good quality double insulated wire for direct feed from the battery bank, consider buying "meter tails" from an electrical supplier. It is sold by the metre, with various amperages, and the inner is colour coded either red or black, but with new IEEE regulations it will be skyblue pink and orinoko