Windlass Battery - deep cycle or starting?

[Stu Jackson]

Could the poster(s) who mentioned charging their windlass battery bank by INVERTER please explain how that works?

[btrayfors]

Originally Posted by Stu Jackson

Could the poster(s) who mentioned charging their windlass battery bank by INVERTER please explain how that works?

Easy peasey, Stu: the inverter provides 120VAC to the battery charger....same as shorepower.

No, it's not the most efficient way, but it works just fine when the engine is running and there's plenty of amps to spare :-)

Bill

[evm1024]

In my case

shore power or battery to inverter/charger which gives 120 vac

120 vac to charger in bow of boat where the AGM battery for the windless is.

Charger to AGM battery.

Under shore power the Windless charger keeps the AGM topped off.
Under battery power I run the inverter for enough time to bring the agm into float.

When running under the inverter it is best to keep the engine running - but - with 700 ah LiFePO4 house bank I can run the inverter off the battery for hours and then let solar recharge the house bank.

Not at all optimal - losses in the inverter, losses in the charger.

With 120 vac I get to run much smaller wire to the forward charger. When I install a bow thruster and a larger battery to power it I would just need to install a larger charger (currently (Hah! no pun) have a 10 amp charger).

[Stu Jackson]

Originally Posted by btrayfors

Easy peasey, Stu: the inverter provides 120VAC to the battery charger....same as shorepower.

No, it's not the most efficient way, but it works just fine when the engine is running and there's plenty of amps to spare :-)

Bill

Bill, that's what I thought, simply wanted confirmation. Some folks (of curse, NOT on THIS forum!) confuse chargers and inverters when they have combined I/Cs, I see it all the time.

And, it would seem to me, with a combined I/C one couldn't do that.

Thanks.

[btrayfors]

Originally Posted by Stu Jackson

Bill, that's what I thought, simply wanted confirmation. Some folks (of curse, NOT on THIS forum!) confuse chargers and inverters when they have combined I/Cs, I see it all the time.

And, it would seem to me, with a combined I/C one couldn't do that.

Thanks.

Actually, you can. And I do. The trick is to use the combined I/C as an inverter to power the 120VAC system on the boat, and to use a separate charger (like my Iota DLS-55/IQ4) to charge the windlass batteries :-)

Not fair, I know :-)

Bill

[Cheechako]

Originally Posted by StuM

+1. Doesn't matter what sort of battery you are using, it's not good for the windlass to pull up to the anchor.

Every boat I've had with electric windlass I have pulled the boat up to the anchor with the windlass (unless it's blowing hard, then I motor of course) It's almost no load on the windlass at all, a little nudge and the boat moves forward. The catenary in the chain pulls the boat forward after that nudge.
You can test this by simply stepping on your anchor chain in front of the roller at anchor, the boat moves forward with almost no effort. Try pulling up the weight of 90 ft of chain and anchor by hand for comparison... far, far more strain on the windlass.


Why do some windlass manfacturers put in their instructions to not do this? Simple, there are many people who have no inkling about mechanical things that will try to pull their boat up to the anchor in 30kts of wind in a continuous pull burning up the cabling, motor or breaker.

[ramblinrod]

Originally Posted by Stu Jackson

Bill, that's what I thought, simply wanted confirmation. Some folks (of curse, NOT on THIS forum!) confuse chargers and inverters when they have combined I/Cs, I see it all the time.

And, it would seem to me, with a combined I/C one couldn't do that.

Thanks.

Hey Stu,

Did you have initial thoughts that someone invented a perpetual motion machine? ;-)

12 Vdc house bank aft, to 120 Vac inverter, to 120Vac charger forward, to 12 Vdc windlass/thruster battery.

Lots of conversion losses, but it works, and potentially saves a cable run, since the 120Vac wiring is already up there.

[Stu Jackson]

Originally Posted by btrayfors

Not fair, I know :-)

Too true!!!

I don't have a second separate charger.

[Jim Cate]

I must admit that I am somewhat astonished at the complexity and expense that folks will undertake just to avoid running some appropriate cables from t he main battery bank... you know, the big one that you already have and are used to monitoring and maintaining.

jim

[Maine Sail]

Originally Posted by Jim Cate

I must admit that I am somewhat astonished at the complexity and expense that folks will undertake just to avoid running some appropriate cables from t he main battery bank... you know, the big one that you already have and are used to monitoring and maintaining.

jim

I just looked up an invoice from last spring. I billed the customer for 38' of 4/0 for $321.00 for that run. Seeing as he already had a massive AGM bank some 4/0, some lugs, heat shrink a couple of fuses etc. and he was on his way. We ran the numbers for a dedicated AGM bow bank, means to charge, box, switch etc. and the 4/0 run came out considerably less. Heck the longest run of wire was from under the v-berth to the windlass motor not back to the house bank on that boat...

[a64pilot]

Originally Posted by Jim Cate

I must admit that I am somewhat astonished at the complexity and expense that folks will undertake just to avoid running some appropriate cables from t he main battery bank... you know, the big one that you already have and are used to monitoring and maintaining.

jim

You said it better than I could, but I have been thinking the same.
I want all my batteries in one place or at least all of them as part of a bank.
I had people advise me I needed a separate start battery for the engine and another separate start battery for the generator? Then I guess the two house banks?
I have essentially one bank although it can be separated with the combiner switch, ran a cable to the generator from the engine start solenoid, and cables to the windlass from the house bank

[ramblinrod]

Originally Posted by Jim Cate

I must admit that I am somewhat astonished at the complexity and expense that folks will undertake just to avoid running some appropriate cables from t he main battery bank... you know, the big one that you already have and are used to monitoring and maintaining.

jim

When considering high DC current loads forward, one has to review the options.

For short cable runs (e.g. 40 ft return) and lighter loads (e.g. 100 A max for a 1200W windlass), running battery cables to the bow from an existing house bank midship is often least expensive and easiest to maintain. (Even though, I don't like batteries in the cabin.)

However, for long cable runs (e.g. 100 ft return bow to under cockpit aft) and higher loads (e.g. 350 A for a good sized bow thruster) the cable costs become excessive, beyond 4/0 marine grade cable, most likely switching to untinned welding cable. In this case, dedicated forward batteries are almost always warranted.

Now all one has to do is figure out where to locate them and how to charge them.

When installing a bow thruster on a boat with an existing windlass powered by the aft house bank, we have to consider some options. Perhaps a better solution is to mount a dedicated battery forward, rewire the windlass to it, and use the prior windlass cabling for connection to an echo charger on the house bank. (Much heavier cabling than required.)

Maybe we can use the original windlass cables to pull lighter echo charger cable, give the owner a bit of a credit, and use the pulled windlass cables for another price sensitive project where used cable is acceptable.

To run cables the full length of the boat can take hours, especially if one is loathe to placing them in the bilge, and tearing the boat apart and then putting it back together, (emptying and repacking every friggin' locker) if the manufacturer did not have the foresight to include accessible raceways.

For a large boat with long cable runs and high power bow thruster and windlass, using an existing on-board generator to power a dedicated new 120Vac charger forward to recharge a new 12Vdc AGM thruster/windlass battery bank, may be the best solution.

There is no single solution for every installation and numerous factors have to be considered to arrive at the best solution for this instance.

But I concur, it has to be a pretty big boat with pretty high loads, to warrant a dedicated battery and some with smaller boats, lighter loads, and shorter cable runs are ill-advised to use a dedicated battery.

RamblinRod
Marine Service Provider
About Sheen Marine

[SailRedemption]

Jim,

I understand what you're saying and I agree for some boats. But mine I don't believe would be cheaper for cables. I have a 47' boat with the lithium batteries located under the bunk in Port aft cabin, the run to the panel was 30' one way, granted I had to cross the boat, and I'm sure the run forward to v berth would be around 40'. That's 80' total run, and I was looking at a Maxwell RC 10-10 windlass which draws 100a. According to the manual they require at most a 10% voltage drop. Using my blue sea wire size app, it tells me for two minutes of time at 10% drop I would need 1awg wire. That's bare minimum.

Looking on Defender for that wire would be $400 for that size for a red and black and 25lbs of wire. Genuinedealz for a made up one would be $320, neither including shipping.

Now I already have a brand new Sterling ProCharge Ultra 20a charger and a fairly new Optima battery that I was going to use. Granted if I didn't have a new charger and battery it would be different.

I'm not there yet for the windlass install but since looking for amp draw for that Maxwell I see its on sale (: Just trying to see what works best for me as I have been trying to sell that charger. I just figured I could use what I had on hand.

Ronnie

See more @ redemptiverepair.com


See more @ redemptiverepair.com

[evm1024]

I was on a boat where for a number of reasons the start battery would not crank the engine and the house battery was also unable to start the engine.

We did take the windless battery and used that to start the engine.

Not saying that one should count this as a plus - But, it did save the day.

[SeaSon]

.

There is no single solution for every installation and numerous factors have to be considered to arrive at the best solution for this instance.




So RamblinRod, for a windlass/thruster powered by a dedicated battery, with a dedicated charger, is it best to use a deep cycle or start battery?