Powering a windlass

[maxi77]

Umm - how do you decide the required current carrying capacity to size the cable? As I implied earlier, with a heavily discharged windlass battery and fully charged 'daisy chained' battery the charging current could be very high when the VSR closes.

Indeed, and on my Bongo I actually use the VSR to switch a heavy duty relay, mind you though as long as you protect the more sensitive bits of the system the periods of high current will be relatively short and I would not plan on using the windlass without having the engine running any way so I would not expect to have to deal with any more than the alternator output which is presently 35 amps on my present set up and will probably rise to 70 amps thiis year.

 

[mitiempo]

Ideally there will be a fuse near the battery. The 35 amps from the alternator is one thing but a shorted battery is another. ABYC calls for all batteries to be fused within 7" of the battery with the exception of start batteries but they can be fused as well.

 

[VicS]

how do you decide the required current carrying capacity to size the cable?

I would size the cable to take the full alternator output current with acceptable volts drop.

Dont know the alternator size or the cable run length for certain but I reckon it will come out at AGW 0,1 or 2

Those sizes if run with free ventillation will carry 180 to 240 amps so I reckon will handle the high current you might get initially.

However probably getting to the sort of size that the OP was hoping to avoid!

So back to the battery to battery charger or Mitiemo' s Xantrex Echo Charge

Probably then be looking at around AWG 6 cables to avoid excessive volts drop but as light as AWG 9 might be acceptable.

Rather like the look of the Xantrex thing!

 

[impact30]

another vote for VSR

but to be fair I have larger loads. I have an 8 meter run to a bow thruster and windlass. I fitted battery bank in the bow charged through VSR. I can use this bank to start my engine if necessary. I used 50mm cable but my demand is quite high.
Cable is fused on both ends.
I was more concerned about acceptable voltage drop than ability to carry current.
I was aware that engine would be more than likely running during windlass and thruster operation contributing to the effort. (also creating large currents in the charging cables)
I have an isolation switch in the bow for the battery bank there.
Padraic

 

[Blueboatman]

Reading this with interest as I have fitted a 1200w winch and now contemplate the wiring.

Reading Nigel Calder and asking a friend who actually installs these things on new boats I reluctantly concur that the battery forward may be the safest and possibly cheaper way to go. Even though he fits ( the factory fits) massive cables that tee off to drive the bowthruster as well ! No comment.
But that leaves the question of where to fit a) an isolator and b) a breaker between winch and power source. If you are operating the winch from a cockpit remote, you don't want to have to scurry forward to reset the trip if it trips out just as the anchor breaks out of the mud.... And you don't really want any electrical components or connectors in the anchor locker in case they get submerged and short out..

Also as Viv says I am still going to have to buy thick charging cable to take the full alternator output when charging. And since voltage drop seems to be the real killer on these systems, having the engine running when lifting the anchor will usefully boost the voltage available at the working battery forward and hence winch performance and reliability...maybe.
The real worry is when the winch comes under near-stalling loads when the amps seem to 'go through the roof', encouraging the real risk of cable melt down with long, marginal cable runs through the bilge, I reckon.
I shall still have to buy a lottery ticket for the short tinned cables 'twixt battery and winch though !

 

[earlybird]

I fitted a Quick 800w winch 4 years ago. It is supplied from the engine start battery by 4awg cables, yes 4, I can hear the toothsucking already!!! This cable is rated at 160amps and protected by an 80amp breaker close to the battery.
This winch will pull my 34' boat up to the anchor quite briskly without help from the engine, (but I don't do this normally ), and lifts the 15 Kg anchor, 8mm chain plus a load of kelp without any apparent strain. I've never yet tripped the breaker.
What am I doing wrong?

 

[willie4646]

Hi Clive, what length of cable run have you got.
Willie

 

[oldsaltoz]

That was my first choice, according to this site http://www.safety-marine.co.uk/Anch...Battery-Cable-(sold-per-meter).htm?P1354-S38-
I will need £450 worth of cable, as indeed my local chandler confirmed, but he will give me 10% off.

.
Have you checked the local scrap metal yard? They often have very new looking cable with heavy duty protective cover, perfect for this. They are off-cuts from high voltage welding leads.

Hope this helps, I have used them a number of times over the years when installing anchor winches for clients.

 

[earlybird]

Hi Clive, what length of cable run have you got.
Willie

12 m total.

 

[mitiempo]

There is no need to run a negative wire to either battery from the Echocharge. The batteries have their negative posts connected to the main ground, or a bus and the main ground which is the engine block. The negative wire from the Echocharge also connects to this bus or the main ground.

 

[Playtime]

There is no need to run a negative wire to either battery from the Echocharge. The batteries have their negative posts connected to the main ground, or a bus and the main ground which is the engine block. The negative wire from the Echocharge also connects to this bus or the main ground.

Eh? How does the battery in the bow get a negative feed then? There is not normally a "bus" running to the bow.

 

[mitiempo]

All batteries, whether in the bow or aft should have their negatives connected to the main ground. ABYC calls for all to be connected at one ground point ultimately, whether direct or through a separate bus. The Echocharge is not unlike a VSR as they also connect through positive to each battery and main ground.

 

[KREW2]

Sorry folks I deleted the post and started a new thread.
Playtime are you saying I need to run a negative from the donor battery to the windlass battery.

 

[Playtime]

All batteries, whether in the bow or aft should have their negatives connected to the main ground. ABYC calls for all to be connected at one ground point ultimately, whether direct or through a separate bus. The Echocharge is not unlike a VSR as they also connect through positive to each battery and main ground.

Don't disagree with that but you will still need a negative wire running to the bow battery regardless of what it is connected to at the aft end!

 

[neale]

I fitted a Quick 800w winch 4 years ago. It is supplied from the engine start battery by 4awg cables, yes 4, I can hear the toothsucking already!!! This cable is rated at 160amps and protected by an 80amp breaker close to the battery.
This winch will pull my 34' boat up to the anchor quite briskly without help from the engine, (but I don't do this normally ), and lifts the 15 Kg anchor, 8mm chain plus a load of kelp without any apparent strain. I've never yet tripped the breaker.
What am I doing wrong?

I'm gonna tooth suck. Assuming your 12m is one way, which I guess it is on an 11m boat, your voltage drop with this set up is over 10%. In my mind this is too much. For your set up I would want 1 awg for a 5% drop.

 

[neale]

I am adding my vote for the Xantrax. I went through the same when fitting a bow thruster. Decided to use a bow battery to power it and also the existing anchor winch. using the Xantrax means only running wires of around 5mm2 the length of the boat.

 

[mitiempo]

If you connect from the Echocharge to the windlass battery or the main ground to the windlass battery it is the same thing in effect. But if the windlass battery is only being used for the windlass as it is the ground wire doesn't have to be of too large a gauge. The positive from the Echocharge will of course have to be lengthened and I would use 10 or maybe 8 awg for this. I think the negative can be the same size as there will only be up to 15 amps travelling through it. Of course the wires from the battery to windlass will be much larger.

 

[mitiempo]

earlybird
I don't think you're really doing anything wrong but I would have used larger wiring. The reason the breaker hasn't tripped is that the duration is short so the wires never get more than a bit warm I guess. With 4awg if the windlass ran longer the wires would eventually get hot.

 

[neale]

neale
I don't think you're really doing anything wrong but I would have used larger wiring. The reason the breaker hasn't tripped is that the duration is short so the wires never get more than a bit warm I guess. With 4awg if the windlass ran longer the wires would eventually get hot.

I think your boat should be addressed to earlybird. If you re-read my post, I am with you and suggest bigger cables.

 

[KREW2]

If you connect from the Echocharge to the windlass battery or the main ground to the windlass battery it is the same thing in effect. But if the windlass battery is only being used for the windlass as it is the ground wire doesn't have to be of too large a gauge. The positive from the Echocharge will of course have to be lengthened and I would use 10 or maybe 8 awg for this. I think the negative can be the same size as there will only be up to 15 amps travelling through it. Of course the wires from the battery to windlass will be much larger.

Is it ok just to add larger positive cable to the smaller one attatched to the echo charger?