Windlass battery charging

[bromleybysea]

I'm considering fitting an electric windlass. I could run heavy cables from the main battery bank to the windlass- about 18m return distance, but it will be a right PITA routing through the bilge, bulkheads etc., and suitable cable is expensive. I have to hand a new spare starter battery and I do have room in the forepeak for a suitable enclosure. I was wondering if an alternative option would be to buy a battery to battery charger, one of the low-output ones like the Stirling and use that to charge the windlass battery. Such a setup would cost less than half that of using heavy battery cable. When cruising I do tend to use marinas every few days and so am hooked up to the mains, and my main battery bank is kept pretty well charged by a combination of engine use and a solar panel. Any advice welcome.

 

[PaulRainbow]

Sounds like a good plan to me :encouragement:

 

[pvb]

The Sterling Battery Maintainer would do the job, but you should note that it needs at least 13.3v on the main battery before it will start working - do you get this with your solar input? If not, it will only charge the windlass battery when the engine's on, or if the main charger's on. At perhaps 2A charge rate, will this be enough to replace the power used by the windlass?

Note also the need to have a fuse in the cable next to the windlass battery.

 

[Boathook]

I've used a battery to battery system for my windlass and bow thruster battery for years now. Seem to remember that it is an Adverc ? rather than Sterling. Shows how much I inspect it nowadays ! As mentioned elsewhere it needs to sense a high voltage on the main battery before allowing windlass battery to be charged.

 

[VicS]

If you power the windlass direct from the starter battery you will have the advantage that with the engine running the alternator will be charging and providing a more oomph.

Various schemes discussed here in the past seem to have no overall best method based on technical merit. It mostly seems to come down to convenience, practicability, cost and personal preference

 

[William_H]

I would persevere with trying to find cheaper heavy cable. I can't imagine that cable is twice the cost of battery and charger.
Another battery to get old and need maintenance is the last thing you need. Plus as Vic said by running off the engine starter battery you will be providing power direct from the alternator (with engine running) as well as from the battery. With a small b to b charger you will not get much charge current help when winching. olewill

 

[jiris]

I'm considering fitting an electric windlass. I could run heavy cables from the main battery bank to the windlass- about 18m return distance, but it will be a right PITA routing through the bilge, bulkheads etc., and suitable cable is expensive. I have to hand a new spare starter battery and I do have room in the forepeak for a suitable enclosure. I was wondering if an alternative option would be to buy a battery to battery charger, one of the low-output ones like the Stirling and use that to charge the windlass battery. Such a setup would cost less than half that of using heavy battery cable. When cruising I do tend to use marinas every few days and so am hooked up to the mains, and my main battery bank is kept pretty well charged by a combination of engine use and a solar panel. Any advice welcome.

I've been using this system for about 3 years now and happy. The reason a bit different. My windlass i24 V and the rest of the boat 12 V...

 

[Chris_Robb]

I have had a sterling 30 amp battery to battery charger installed from my engine battery to the 110a/h forpeak battery (running anchor winch and bow thruster) since 2008. I installed reasonably heavy cables to account for the voltage drop at higher currents. The bow battery was originally installed (AGM Life line) in 2004 and just had its own charger as the boat was marina based.

The sterling B to B charger has worked perfectly and kept the battery fully charged, aided by 170watts of solar power.

Its a good system - but you still have to run quite sizable cables to ensure no voltage drop.

 

[pvb]

I have had a sterling 30 amp battery to battery charger installed from my engine battery to the 110a/h forpeak battery (running anchor winch and bow thruster) since 2008. I installed reasonably heavy cables to account for the voltage drop at higher currents. The bow battery was originally installed (AGM Life line) in 2004 and just had its own charger as the boat was marina based.

The sterling B to B charger has worked perfectly and kept the battery fully charged, aided by 170watts of solar power.

Its a good system - but you still have to run quite sizable cables to ensure no voltage drop.

The OP said he was looking at a Sterling product which would be half the price of running cables, so I guessed he meant the Battery Maintainer, which is about £70. This only charges at about 2A, so light cables are sufficient. The sort of charger you have is over £200, so I don't think he was considering that.

 

[matthewriches]

You say heavy cable but what winch are you fitting? Not going to be too heavy in comparison to a bow or stern thruster.

We tend to run the thick cable as it is a "proper job" so to speak. 2 less things to go wrong (the actual battery and the b2b charger), system easier to repair in the field if it ever goes wrong, additional power from the engine(s) if suitably wired, etc...

If you buy the cable from the right place to get the right price, you'll end up with a far superior install.

 

[PaulRainbow]

The OP said he was looking at a Sterling product which would be half the price of running cables, so I guessed he meant the Battery Maintainer, which is about £70. This only charges at about 2A, so light cables are sufficient. The sort of charger you have is over £200, so I don't think he was considering that.

I assumed he was planning to fit a B to B charger, as he said "buy a battery to battery charger".

But you are correct, the costings don't add up. Perhaps the OP would clarify exactly what it is he was proposing ?

 

[pvb]

I assumed he was planning to fit a B to B charger, as he said "buy a battery to battery charger".

But you are correct, the costings don't add up. Perhaps the OP would clarify exactly what it is he was proposing ?

I think it's the Battery Maintainer, listed in Sterling's Battery-to-Battery Charger section.

https://sterling-power.com/collecti...roducts/battery-to-battery-charger-maintainer

 

[PaulRainbow]

I think it's the Battery Maintainer, listed in Sterling's Battery-to-Battery Charger section.

https://sterling-power.com/collecti...roducts/battery-to-battery-charger-maintainer

Yoy might well be right, but i assumed that when he said he was fitting a B to B that's what he was fitting.

Post #2 was based on that premise, if it turns out he's talking about a 2 amp device, then my advise would be different. The B 2 B is suitable, the battery maintainer isn't. If it's just about saving a few quid on cable, i'd say forget it and fit the cables.

 

[pvb]

Yoy might well be right, but i assumed that when he said he was fitting a B to B that's what he was fitting.

Post #2 was based on that premise, if it turns out he's talking about a 2 amp device, then my advise would be different. The B 2 B is suitable, the battery maintainer isn't. If it's just about saving a few quid on cable, i'd say forget it and fit the cables.

He only wants it to recharge a windlass battery. Getting the anchor up would only use a few Ah, maybe 4Ah. So around a couple of hours motoring, or a decent solar charge rate, and the battery should be recharged.

 

[simonfraser]

KISS, reduce the bits to go wrong, get the bigger cables and wire it up to your existing starting battery, only use it with the engine running.
Drill the various holes too big, you’re bound to think of another ‘improvement’