Windlass to which battery bank?

FirstAway

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Following on from another thread I am curious as to which batery bank the windlass is normally connected?

I have an 85ah engine battery, 2 x 100ah service batteries, a 60 amp alternator, 2 x 100w solar panels, a 1000w windlass. The solar panels are connected to the service bank only, there is a Victron battery combiner but I am not convinced it is working properly. The windlass is connected to the service bank. The boat is in Greece so the panels work well, and the windlass is used a lot.

I read in another thread that it might be better to have the windlass running from the engine battery. This sounds more logical to me as presumably close to the full alternator output would be used to power the windlass, rather than depleting the service batteries at the end of the day, just when the sun is going down and and you want them full.

What do others think, is there any disadvantage in swapping the windlass across to the engine battery?

Many thanks

Bob
 
Mine is on the house bank. Don't connect it to the engine battery, because if you have to muck about with your anchor on night, you might then find that you can't get your engine started.

As a general rule however, I tend to make sure that I've got the engine running before using the windlass.
 
Even though the windlass is rated at 1000W (potentially 120A), for most of the time when it is hauling in chain it will only be taking about 30A; only when struggling to break out the anchor will it be taking close to 100A, and even then only for a few seconds. Connect to house bank.

My view is the engine starter battery is exactly that - engine starting.
 
Some argue that it should be on the start battery because you normally run the engine when using the windlass. However that gives very limited capacity if you want to use it without running the engine - but on the other hand if you are running the engine the house bank is being charged as well.

So, preference is that it should be the house bank as this gives you more flexibility and leaves the start battery to do its dedicated job without the risk of running it down.
 
It's tempting to answer 'the nearest one'.
But I agree, the engine battery is just for starting the engine. Otherwise there is very little point in it being separate at all.
 
I noticed on another thread that it was suggested that the windlass would be powered from the starter battery, and it made me scratch my head in bewilderment. I would always recommend using the service batteries for all services, and keep the starter battery for just that.

I am confused by FirstAway's worry about depleting the service batteries in the evening, presumably from the use of the windlass. How does that happen? Are you on the nightshift? :D. Or are you one of those people who feel the need to push your anchor down through the water? :D Gravity works for me, so my windlass is only used for lifting the anchor, and not always with the engine running.
 
In general I agree that the services batteries are better than the starting battery, but I think that people overestimate the power usage of windlasses. I have a 70AH engine battery and a windlass that takes about 100 amps max, though mostly when running almost certainly a LOT less. Assuming (very pessimistically) an average 70 amp draw, you'd have to "windlass" for 30 minutes to use half battery capacity. A typical usage might be 3 mins max - ie just 5% of battery capacity.

It is really useful to be able to run the windlass without the engine at times, hence my preference for connection to services batteries, which in any case are often of greater capacity than the starting battery. A dedicated windlass battery in the bows is of course best of all, and it doesn't have to be huge - 20AH would probably be plenty ....
 
My windlass has been connected to the domestic batteries for a long time now, almost coming up to 20 years. The batteries are well aft, connected to the solenoid box using welding cable. Never been any trouble, either for battery capacity or windlass operation. I agree with others, it is very useful to be able to operate the windlass without running the engine, for small adjustments to scope and such like. Charter boats typically have to start the engine, presumably to try to avoid flattening the batteries, but I prefer not to for sensible use.
 
I am confused by FirstAway's worry about depleting the service batteries in the evening, presumably from the use of the windlass. How does that happen? Are you on the nightshift? . Or are you one of those people who feel the need to push your anchor down through the water? Gravity works for me, so my windlass is only used for lifting the anchor, and not always with the engine running.

No I am afraid that I am one of those people that sometimes needs more than one attemp to anchor. I probably worry too much about being too close to others.
 
Many thanks for all the replies, the windlass is interlocked with the engine ignition so I cannot use it without the engine.

It looks like I should leave it as it is and get the battery combiner sorted properly.

Thanks again

Bob
 
I don't think there is a categorically wrong way to do it, but it does obviously depend upon your circumstances, needs and setup.

For instance, if someone only had a tiny engine battery, a feeble alternator and usually took 100 attempts at anchoring, it might be best if he connected the windlass to the domestic bank (or stay in the marina) :)

I have a similar setup to the OP, big engine battery, decent alternator etc and i prefer to have my windlass connected to the engine battery. My previous boats were also wired this way, the last one being a Jeanneau with the windlass and dual batteries fitted from new. I rarely use the windlass without the engine running and as i have a 700a starter battery i doubt i'd wind up with a flat engine battery even if i did. I still have the options to start the engine from the domestics in any event.
 
Many thanks for all the replies, the windlass is interlocked with the engine ignition so I cannot use it without the engine.

It looks like I should leave it as it is and get the battery combiner sorted properly.

Thanks again

Bob


What makes you think it isnt working ?
 
We have a separate battery for anchor winch which is interlocked with engine running it also drives a halyard winch that is not interlocked and can be used when sailing.
I don’t like the fact our practice is to power the chain down but am overruled and am wary that it cannot be jumped in an emergency.
We also had a problem starting the engine this year that despite have all other batteries renewed was only cured by replacing the winch battery although you can start the engine with the winch battery apparently disconnected.
It’s worked this way for 8 years and due to the wiring being inaccessible will probably stay that way but I don’t like it.
 
get the engine running before you haul, if the capstan fails then you can "motor" it out and haul by hand. or ditch the anchor, at least you have a running engine.
 
So if something happens to your engine and you have to anchor for safety reasons, which battery would you want to start draining using the windlass?

OK, most windlasses allow you to dump the anchor and chain, but that not the best way of laying chain out evenly on the seabed, especially if you haven't time to brief your inexperienced crew properly.

And of course windlasses don't take that much power powering the anchor down.
 
It is better to have high power 12v devices with their own battery as close to the consumer target, windlans, bow / stern truser etc equimpments. Or, if not possible, the electric cable must be correctly dimensioned across the surface for long distance
Installation

Cause, it is possible litle risk if the device does not get enough power, its solenoid will start to heat and weld cloused and the device will continue to operate even if the switch is turn off.

NBs
 
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I am confused by FirstAway's worry about depleting the service batteries in the evening, presumably from the use of the windlass. How does that happen? Are you on the nightshift? . Or are you one of those people who feel the need to push your anchor down through the water? Gravity works for me, so my windlass is only used for lifting the anchor, and not always with the engine running.

No I am afraid that I am one of those people that sometimes needs more than one attemp to anchor. I probably worry too much about being too close to others.

Fair enough.
 
What makes you think it isnt working ?

I find it difficult to tell with the panels and the alternator feeding in, but the domestic voltages don’t look as high as I would hope when the engine is running. Of course when there is a high load like using the windlass I am usually on deck and don’t check the gauges.

Bob
 
We inherited a system which ties alternator to the engine ignition and wanting windlass without the engine isn't a problem in the top 100 things that need doing next. We never use the electric windlass when setting anchor and can haul it manually but I've tended to spend an extra day at anchor sorting out the engine when we've had problems, including once getting a part shipped then flown in, which meant three days in a turquoise bay waiting.
 
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