Windlass Battery - deep cycle or starting?

[rha9]

I am installing a remote battery to power a windlass. Have the charging circuit figured out, but not sure what type of battery to get. Seems like the starter battery (high charge demand for a short time) is closest to the windlass requirement, but the operating time would be somewhat longer than typical for a starter motor. Anyone with experience on this?

[StuM]

Say you have a 1200W motor, that's about 100A. You will generally run the windlass for less than 6 minutes so you are looking at pulling less than 10Ah out of battery.
I'd go with a starting or multipurpose battery.

If you are running a separate battery connected to the rest of your system for charging, remember that you generally anchor with your engine running so the alternator will be pushing out lots of Amps towards your battery/windlass. IOW, you need to wire your charging circuit with the same gauge as you would if you were running your windlass directly off your house bank. (Which raises the question - why go through the hassle of a separate battery and another charging circuit )

[Frankly]

I include my fwd battery (2 GC in series) as part of my house bank. All the house bank does not need to be in a single location. Some imbalances will exist with different loads from time to time but they will all equalize with a little time. Just connect all the banks with some reasonable size wire and fuse the connecting wire on each end. Operating this way for years with no problems and also have a bow thruster. The bow thruster draws a little north of 300 Amps, 200 from the fwd bank and 100 from the aft. Don't see hauling all that lead around just for a few AH each morning.

[Vasco]

Originally Posted by StuM

(Which raises the question - why go through the hassle of a separate battery and another charging circuit )

Yes, why? Do you need more weight in the bow?

Sent from my SGH-I747M using Cruisers Sailing Forum mobile app

[StuM]

How do you control the Amp draw between the two banks?

[a64pilot]

I was under the impression that a deep cycle could function as a start battery?


Sent from my iPad Pro using Cruisers Sailing Forum

[a64pilot]

Originally Posted by StuM

How do you control the Amp draw between the two banks?

If he is set up like I am, and it sounds as if he is, you don't. In essence you have one bank really, just part of it is located differently.


Sent from my iPad Pro using Cruisers Sailing Forum

[Reefmagnet]

There are some reasons to use dedicated anchor winch battery. For example, to compensate for voltage drop caused by under rated wiring from the power source back far in the vessel. But it seems like the OP is going to power the winch independently of the main power circuit? In this case, you'd probably want a deep cycle battery that will not reduce below 50% amp/hr discharge for the longest anticipated operation time of your winch. If it is just to compensate for insufficient cabling, then a battery acting more like a "super capacitor" is probably better. Something like a small motorcycle battery with a chemistry matching your existing house bank.

[evm1024]

Same questions been running through my mind...

In the short term havig converted to a LiFePO4 house bank I put an AGM in for the start battery and for the windless battery.

These AGM are charged by their own dedicated 10 amp charger (Xantrex truecharge 2 the newer model).

Not the best option in my mind but "it works" and keeps the AGM and Li chemistry apart.

At the dock I just turn the AGM chargers on shore power and let them take care of the batteries.

Cruising, I turn on the inverter after starting the engine and then raise anchor. If I need to motor awhile the chargers do their thing. And the inverter charger charges the house bank. If I don't need to run the engine then I decide when to shut it off and monitor the AGM chargers and when they enter float (of sooner if wanted) I shut down the inverter.

Solar them brings the house bank back up as normal.

REgards

[Sandero]

I've never understood the idea of a windlass battery. IIRC the instruction manual for the Maxwell advises that the engine be running... and it's not a bad idea in any case... weighing or laying the anchor.

If you have an high output alternator... with a smart regulator... it will sense a large draw and put out more amps. The battery bank should be drained by this. Of course a decent size house bank also is a good idea.

You do need to run some decent size wire to the windlass because the current is pretty large... so the wires would be larger than to charge a windlass battery. And of course you add a lot more weight to the bow with a windlass battery.

[Frankly]

You don't worry about what battery contributes what. The fwd and aft banks are connected by #2 cable with 150 amp fuses on each end. If I run the bow thruster or windlass the voltage in the fwd bank will be down slightly. Because of this slight voltage imbalance current will flow from the aft bank to the fwd bank until the voltages are again equal. The aft will decrease slightly and the fwd increase. Works both ways.

Don't have a starting battery just 660 AH of LAGC batteries (starting and house).

[skipgundlach]

Originally Posted by a64pilot

I was under the impression that a deep cycle could function as a start battery?


Sent from my iPad Pro using Cruisers Sailing Forum

Emphasis added...

My experience, in starting our Perkins 4-154, with our 740AH 4xL16 is that I can turn the crank forever - but not very fast.

The thinner (and more numerous) plates in my plain-jane starter battery, alone, however, will spin her right up and it's a quick start.

As it happens, as I'd always be in charge mode during engine run, anyway, I put the switch to 'both' - and the available much higher amps of the start battery dominates when I start; both the house bank and my windlass and start battery (on a pair, through a combiner) will charge as I'm running.

As my windlass battery is right next to the windlass in the Vee (maybe 4' run), my charging cables don't take the load and thus can be smaller. I don't recall for sure but I think the cables to the windlass from the battery are 00 or so, but the charge cables (perhaps a 25' run) are more like #2 or so.

As neither gets a very long workout, the windlass and start batteries are pretty much fully charged all the time, whereas I allow my house batteries to go as low as 50% discharged. My norm is more like not over 35% discharged, but if it works out that way, 50% isn't a big deal - and, yet, both the start and windlass batteries remain up.

A hybrid start/deep cycle battery, I suspect, gives you the downsides of both in one package...

[pitlaw]

I decided to use a seperate forward battery for my windlass because the cost of heavy copper cables running from the house bank was high and more than a seperate battery with smaller charging cables. Also less power lost at the wndlass. It charges on the same bank with no special routines. So why not? Also it is the same type as my starter battery. No problems at all.

[wayne.b]

Originally Posted by rha9

I am installing a remote battery to power a windlass. Have the charging circuit figured out, but not sure what type of battery to get. Seems like the starter battery (high charge demand for a short time) is closest to the windlass requirement, but the operating time would be somewhat longer than typical for a starter motor. Anyone with experience on this?

===

Two years ago we switched our windlass battery over from an 8D marine battery to a pair of group 31 AGMs in parallel. They have about the same cold cranking amps as the 8D and voltage under load seems a bit stiffer. Of course they're also much easier to handle. So far so good.

[pitlaw]

Buy the same type battery as you have in the house bank,i.e. Agm for agm or wet cell for wet cell. Mine is a group 27 agm with a 1500W Lofrans Tigres. Works fine.