Windlass Battery - deep cycle or starting?

[Cheechako]

Originally Posted by 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.

It does raise the question... do you need huge cables running forward to a windlass battery? if it's part of the house system, the aft house bank will fill the forward battery as it's being depleted right? How much current would that be..?

[roland stockham]

Originally Posted by 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.

Absolutely right you use a start battery because it is high current/low cycle depth. Deep cycle and start batteries should not be mixed on the same circuit as the have different charge characteristics, particularly don't mix flooded and sealed so should be on the engine battery charge circuit.
From and electrical point trying to run an 80ft loop DC high power circuit just does not make sense the losses mean you will get less performance from the windlass.
I remember at school when we where learning about AC & DC electricity doing an experiment where there were a set of power lines about 20ft long down one bench with a bulb at the end to represent the power grid. If you put 12v AC into the lines the bulb lit, if you did it with 12v DC nothing happened, same voltage, same load but DC just does not like to travel. So even if you can afford the cost and weight of all that copper it will still work better if you run it off a battery.

[a64pilot]

Originally Posted by Cheechako

It does raise the question... do you need huge cables running forward to a windlass battery? if it's part of the house system, the aft house bank will fill the forward battery as it's being depleted right? How much current would that be..?

No, assuming you size your windlass battery appropriately, then all you really need to do is re-charge it.
If your going to run massive enough cables so you don't get a voltage drop, then you don't need a separate windlass battery.

I did what it sounds like Frankly did, I essentially have one large 660 Amp bank, and ran #2 cables to the windlass. I have not measured voltage drop, but windlass sounds fine, it's does not drop RPM under load. Now I don't think I have ever run it more than 60 sec either.
I have no idea what the duty cycle of a windlass motor is, but they look a lot like a starter motor, and if so then they aren't meant to be run for minutes at a time.

[Greg4cocokai]

Originally Posted by StuM

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

I believe my battery combiner limits current to 60amps. I ran #4 wires to charge a large (group 120?) battery. 50' run one way, 2200w windlass, 125 lb anchor, 400'-3/8" chain. Circumnavigated 9 yrs with no problems except one battery changeout.


Sent from my iPhone using Cruisers Sailing Forum

[TheThunderbird]

54' boat 75lbs anchor.
Windlass 1500W
Bow-thrust 5300W !!!

Currently there are big wires coming from engine batteries 2x200Ah
I use them always with engine on.

In the future, an intelligent upgrade could be a LiFePO battery dedicated to bow-works

As cranking is the issue, I was told of approx.20Ah battery being enough with that technology, which allows the highest discharge current rate!

Thus...

Lower battery weight, shorter connection, smaller cables (fuse now is 400+A)

Note: Lithium batteries are quite expensive (approx. 4X lead acid ones, even considering that you need power installed capacity...).
But they make much sense when you consider the practicality of
- size/weight
- high discharge currents
Although.... considering the control system for just one battery sounds impractical for now...

[a64pilot]

I cut and pasted this from the trojan site, to answer the original question, why have a starting battery on a boat? Why not all deep cycle?

Can I use my deep-cycle battery as a starting battery?
deep-cycle batteries can be used for engine starting but starting batteries should not be used for deep-cycle applications. A deep-cycle battery may have less cranking amps per pound than a starting battery, but in most cases a deep-cycle battery is still more than adequate for the purpose of starting an engine

Trojan Battery Company

[mcarling]

The advice to run the engine when using the windlass predates LiFePO4 batteries. LiFePO4 batteries obviate any need to run the engine when using the windlass, which is really nice for the other people in the anchorage.

I've seen 12C discharge loads with LiFePO4 for durations similar to those for a bow thruster, with no obvious ill effects, though I believe cycle life will suffer. Given how often a bow thruster is used, that might be acceptable. So assuming the bow thruster and the windlass probably won't be used at the same time, a 10C discharge load would result from a 530 watt-hour battery, which would be 40AH at 13V or 20AH at 26V. I would go with double that capacity if I had the space.

[zstine]

I have a separate deep cycle battery for the windlass..

Originally Posted by StuM

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

I have a remote battery in the bow for 2 reasons. 1) it is cheaper to add a battery then buy high amp 00 wire to run from the house bank to the bow. 2) it is easier to install a battery than fish heavy copper wire.. so there's no hassle to be had.

Currently, I run a deep cycle lead acid battery and I am a weekend cruiser with the occasional week away. Right now, I do not have a way to charge my windlass battery off the engine save am emergency 20ft jumper cable which has never been used. 90% of the time, I charge it with a $20 trickle charger off my 120VAC outlet when back dockside. On longer cruises I plug in a 15W solar panel at anchor. The battery is deep cycle because I regularly run several anchor operations without recharging. Three years without problems doing this. I believe I can run about a half dozen cycles before worrying about depleting the battery below 50%.

That said, I do plan to do some extended cruising and will add some charge wires aft. These don't have to be rated for the windlass load as they are just going to push a charge amperage and long/small wires will add resistance = less current. So the windlass will draw mostly off the battery in the bow, not the charge lines if connected to the house bank. Certainly will fuse the charge line. Another option is putting the windlass charge lines on an echo charger vice to the house bank. Basically making it a separate bank and limits line current to 15A, which would only need like 10awg for 20ft run.
Xantrex Echo-Charge Digital Auxillary Charger

[MC2019]

Nope, AGM or GEL you don't want CCA you want continuous duty amps.

[Stu Jackson]

Originally Posted by mcarling

,,,,,,,,,,,,obviate any need to run the engine when using the windlass, which is really nice for the other people in the anchorage.

Not sure I understand this at all. My engine spurting water out the back is a LOT quieter than the sound of my anchor chain going over the roller as it comes up.

Could you please explain? Thanks.

[Island Time O25]

Don't recall now the exact reasons I was given independently by several marine pros but all were of opinion that given a choice of running a heavy wire to the windlass or installing a separate battery at the bow with a short run the latter is a better choice. Picked up the last 10ft out of the spool of 00 wire at WM for a few bucks (at about $2/ft) so that sealed the choice for good.

Haven't installed a charging wire yet as I rarely anchored since installing the windlass (funny how I was anchoring a lot when it was a manual chore) so I used a clip on wire and a 20W flex solar panel with a small 7A controller to top the battery off. But I do want to run the charging wire though before splashing this spring.

[mcarling]

Originally Posted by Stu Jackson

Not sure I understand this at all. My engine spurting water out the back is a LOT quieter than the sound of my anchor chain going over the roller as it comes up.

Could you please explain? Thanks.

Noise is cumulative. Glad to read that your engine is quiet. Many are not.

[valhalla360]

Assuming all else is equal a deep cycle of the same size (but obviously rated high for enough amps to operate the windlass) would be preferable (assuming you are putting in a separate battery).

Of course all things are not created equal and assuming you keep the engine running, it's not a big deal on wa or the other.

[Stu Jackson]

Originally Posted by mcarling

Noise is cumulative. Glad to read that your engine is quiet. Many are not.

Thanks, helpful answer.

[TheThunderbird]

Originally Posted by zstine

I have a separate deep cycle battery for the windlass.


Another option is putting the windlass charge lines on an echo charger vice to the house bank. Basically making it a separate bank and limits line current to 15A, which would only need like 10awg for 20ft run.
Xantrex Echo-Charge Digital Auxillary Charger

Sir, the full-fledged would be wired to the house bank, or to its charger ?

Many thanks!