Windlass, battery, solar panel

[zstine]

I have a group 27 (maybe 29?) on my windlass with a 44lb plow and all chain. I charge with a pair of 15W panels I just set out on deck. 2-3 hours of sun will recharge 1 anchor evolution. This past weekend I ran 4 anchor evolutions without charging and the battery was still showing 12.4V. My windlass draws 50-60Amps, but I run it for less than 5 minutes to haul 100ft of chain... that's under 5Ahr per evolution (i free fall drop). So there's plenty of juice to anchor a few times. I have long jumper cables that reach from my windlass battery to the main bank if I need it in an emergency, but have never had any issue...

[Bulawayo]

Despite what other say I do not consider a car battery at all suitable and the reasons you have given are also correct. In addition, a starting battery is constructed to give a high discharge for a short period, like starting a car engine. It is not suitable for sustained high current discharge. The solar panel shall take a long period to recharge as well and is unlikely to prove up to the job. This is a recipe for failure.

Originally Posted by svinvictus2

This seems to be a poor idea. Not only does a windlass battery need to be charged fully each time but you may find yourself in a situation where you need to anchor and re anchor several times to be safely secured. Without engine or other back up charging ,especially AT NIGHT, you'll be the creek without a paddle.
Any windlass will and can bring the battery charge down extremely fast. Just one of those nights that a storm come running through and you have tyo either pick up and re anchor somewhere else you'll find yourself without a windlass.....not a good idea.

[zstine]

I'm doing this works great and so I have to strongly disagree with Bulawayo and svinvictus2. I have a Walmart deep cycle marine Grp 29 battery that has 125Amp hr rating. My windlass draws 50-60 amps, so this battery can run my windlass about an hour (!) before 50% discharge. Plenty of time to anchor several (a dozen) times in a dark stormy night. Been 3 years with my setup and I have never needed my emergency jumper cables. This setup doesn't need a battery isolater/splitter to charge the windlass battery or 80 ft of heavy cable (round trip) which makes this setup cheaper and a whole lot easier to install. I would tell the OP to go for it! A start battery has no issue dealing with 50 amp draw for a few min. That battery may even be better suited than a deep cycle...?
There's no better proof than doing it and it works great for me! There's lots of nay sayers out there.

[Bulawayo]

ZStine, I can accept it working for a short time however I will not agree that my posting is incorrect. There are many factors involved. You can recharge one evolution (whatever that is?) via 30 watts of solar whilst having a windlass that draws 50-60amps? You are recharging a group 29, 125a/h battery? Considering most wet batteries only have a recharge capacity to around 80% that is 100 amps. Take the battery below 50% on a few occassions and you'll dramatically shorten its life. Manufacturers recommend not discharging below 50%. That means you have 50Amps available to you. Over 2-3 hours you are getting perhaps 4-6 amps in total from those solar panels. Run that windlass repeatedly and you'll not see an hours use out of the battery as the heavy load shall rapidly pull down the voltage. This is just like a car battery cranking over the engine. Using simple numbers (and battery power doesnt follow these formats) then your windlass is drawing approx 1 Amp per minute. Your own numbers state that after a 100' chain retrieval with a 44lb anchor you'll have used 5-6amps. That is a three hour recharge by solar panels assuming a high efficiency for one chain and anchor recovery.
Run your windlass 5 times using the same basis (and I repeat that a car battery will not sustain this rate of discharge) and you have 'consumed' 25-30amps of your battery. The battery voltage shall have also fallen to 12.2v or less. That now requires your solar panels to work for around 12-15 hours to recharge your battery - and the sun is not going to hang around for that long to provide your recharging.
You are already in trouble if you need to do another retrieval.
Place yourself in a critical condition and this could easily lead to a life threatening condition. Relying on jump leads is also a false security.
Its your life and perhaps that of others, but I would never consider this arrangement to be acceptable. If you are going to use a similar arrangement then upgrade to Lithium Ion batteries and get bigger solar panels.
If there is an opportunity to connect to a bigger power source why not do this with an inline isolator switch if required.

Originally Posted by zstine

I'm doing this works great and so I have to strongly disagree with Bulawayo and svinvictus2. I have a Walmart deep cycle marine Grp 29 battery that has 125Amp hr rating. My windlass draws 50-60 amps, so this battery can run my windlass about an hour (!) before 50% discharge. Plenty of time to anchor several (a dozen) times in a dark stormy night. Been 3 years with my setup and I have never needed my emergency jumper cables. This setup doesn't need a battery isolater/splitter to charge the windlass battery or 80 ft of heavy cable (round trip) which makes this setup cheaper and a whole lot easier to install. I would tell the OP to go for it! A start battery has no issue dealing with 50 amp draw for a few min. That battery may even be better suited than a deep cycle...?
There's no better proof than doing it and it works great for me! There's lots of nay sayers out there.

[StuM]

Originally Posted by Bulawayo

ZStine, I can accept it working for a short time however I will not agree that my posting is incorrect. There are many factors involved. You can recharge one evolution (whatever that is?) via 30 watts of solar whilst having a windlass that draws 50-60amps? You are recharging a group 29, 125a/h Ah battery? Considering most wet batteries only have a recharge capacity to around 80% that is 100 amps Amp hrs. Take the battery below 50% on a few occassions and you'll dramatically shorten its life. Manufacturers recommend not discharging below 50%. That means you have 50Amps Amp hrs available to you. Over 2-3 hours you are getting perhaps 4-6 amps Amp hrs in total from those solar panels. Run that windlass repeatedly and you'll not see an hours use out of the battery as the heavy load shall rapidly pull down the voltage. This is just like a car battery cranking over the engine. Using simple numbers (and battery power doesnt follow these formats) then your windlass is drawing approx 1 Amp Amp hr per minute. Your own numbers state that after a 100' chain retrieval with a 44lb anchor you'll have used 5-6amps Amp hrs. That is a three hour recharge by solar panels assuming a high efficiency for one chain and anchor recovery.
Run your windlass 5 times using the same basis (and I repeat that a car battery will not sustain this rate of discharge) and you have 'consumed' 25-30amps Amp hrs of your battery.

I don't understand this:

You are recharging a group 29, 125a/h battery? Considering most wet batteries only have a recharge capacity to around 80% that is 100 amps

Ignoring your confusion between Amps and Amp hrs, I still don't understand what you are trying to say. Please explain.

[Bulawayo]

Stu, I am not confused over amps vs amp hours but perhaps I could have explained it better. It is pretty clear what I was stating tho'. The numbers are not sustainable for the battery with the stated windlass and solar panels. The battery shall fail and be wrecked very quickly with sustained use of the windlass. The solar panels are inadequately sized to recharge the battery if its required to perform again within 24 hours.
The 125a/h battery, shall, under ideal conditions. provide 1amp an hour for 125 hours. We all know that when you dump a 50-60 load onto this battery the voltage shall be pulled down super fast. If someone wishes to challenge this then they should take it up with manufacturers. Similarly, it is pretty well documented that wet batteries are very hard to recharge over 80% and with just 30 watts of solar panels you are going to run out of sunny hours pretty rapidly. 30 Watts shall likely produce 2 amps per hour or 2a/h. That is not sustainable for the full day even on the sunniest of tropical days and laying on deck shall produce shadows. The scenario might well work for a while but it leaves the user very exposed when / if an emergency arises. I repeat that it is a recipe for problems.

Originally Posted by StuM

I don't understand this:

You are recharging a group 29, 125a/h battery? Considering most wet batteries only have a recharge capacity to around 80% that is 100 amps

Ignoring your confusion between Amps and Amp hrs, I still don't understand what you are trying to say. Please explain.

[zstine]

I guess it depends on how much you want to be able to pull anchor. When I'm cruising, I usually drop the hook and stay a day.... maybe more. Even if I move daily, that'S anchoring once a day at 5amp hr of use. My 30W can easily handle that. If I have a bad time and have to anchor 5 times... that's 25Ahrs. No, it will not recharge in 1 day... but I can still use it in normal daily use as there'S plenty juice left and the solar will catch up in a few days. No issues. As I said, I've been running this setup for 3 years and never had a problem with killing my battery. ... worse case, I dig out the jumper cables and run off the main bank... if you want to anchor 2 or 3 times a day, get 50W or 100 solar. The method has proven viable, as long as sized for your use

[StuM]

Originally Posted by Bulawayo

Stu, I am not confused over amps vs amp hours but perhaps I could have explained it better. It is pretty clear what I was stating tho'. The numbers are not sustainable for the battery with the stated windlass and solar panels. The battery shall fail and be wrecked very quickly with sustained use of the windlass. The solar panels are inadequately sized to recharge the battery if its required to perform again within 24 hours.
The 125a/h Ah battery, shall, under ideal conditions. provide 1amp an hour for 125 hours. We all know that when you dump a 50-60 load onto this battery the voltage shall be pulled down super fast. If someone wishes to challenge this then they should take it up with manufacturers. Similarly, it is pretty well documented that wet batteries are very hard to recharge over 80% and with just 30 watts of solar panels you are going to run out of sunny hours pretty rapidly. 30 Watts shall likely produce 2 amps per hour or 2a/h.

Clearly you are still confused over amps v amp hours.
http://www.cruisersforum.com/forums/...ml#post1933764

It's the part in bold that has me puzzled. I have no problems with charging LA batteries to well over 80%.

FWIW, I prefer to keep my batteries over 80% as much of the time as possible.

Please provide your documentation that says that wet batteries are very hard to recharge over 80%.

[noelex 77]

Originally Posted by anacapaisland42

Is it possible to run a windlass solely off a good size SLI battery refreshed by a solar panel for a Bruce 33, 150 feet 3/8 BBB chain, 300 feet 1" rode
Tx
Bill

I don't think this is best practice. The windlass is one of those essential pieces of gear that you want as reliable as possible. However, it is doable.

The windlass draws a very high current, but only for a short time. The actual amp hours consumed per lift are reasonably low. But it is very important to consider that a battery's capacity measurement is only valid for a low discharge rate. In this case, you have a high discharge current so the effective battery capacity will be much lower. This effect can be calculated, but at a guess I would work on 1/2 of the stated battery capacity. I would oversize the battery and solar panel size.

It is an ideal application for lithium batteries. The reduced weight in the bow would be a help and lithium batteries can handle deep cycle duty and still provide high discharge currents, something lead acid cannot manage. The capacity of lithium batteries is much less dependent on the discharge rate than lead acid. As you are planning only one charge source (solar) and independence from the main battery bank, the installation would be more straightforward than most lithium battery projects, but you still need some technical knowledge.

The difficulty with many boats is running thick heavy duty cables cables forward. If this is the limitation in your case consider a battery to battery charger from the main bank to a forward battery instead of the solar panel. It still needs some cables running forward, but these can be smaller. This will be more reliable than a solar panel installation as the charging can also happen at night and in poor weather.

[ramblinrod]

Originally Posted by anacapaisland42

SLI battery,,,starting/lighting/ignition i.e. just a plain car battery :-)
Bill

This is kinda strange. You want to "anchor out" in a boat large enough to need a windlass (heavy anchor and chain), and yet all you have is a single "car battery" (assumed starting battery) to power all boat systems?

If it's a small power boat for day use (like a dive boat) with limited "cruising" systems, charge the batteries with the engine alternator.

If you want to go simple in a very small boat, forget the windlass. If you want to cruise a boat significant enough to warrant having a windlass, increase the battery bank, to operate the other electrical / electronic appliances, that will be much more important than the windlass.

You can do as you wish on your boat of course, but the combination of elements in your request is a strange mix for sure.

[anacapaisland42]

Well.....it's like this, the main engine is unreliable and our back-up engine is a permanently mounted outboard, it has it's own battery. We have LED lighting and rarely run the cooler/fridge, the worst demand are the computers/electronics but that is getting somewhat easier to manage.
We get by on 2 house batteries primarily charged by solar.I'm reaching the age (73) where pulling up the Bruce 33, 150 feet of 3/8 BBB (cut down this year from 300 feet) and 300 feet of 1" nylon, is getting to be a chore and, yes, we have had to put it all out 3 times...and wish we had more :-)
After spending 3 months cruising Mexico with no engine thus no power I've decided to keep the battery systems separate, especially the gas guzzling windlass.
We do have a generator but have yet to use it!. However it will be there in an emergency....if I remember how to start it :-)
The SLI was because of the high initial demand, though I'm coming around to a group 27/31 based upon one of the respondents experience,
Anyway......we'll see what happens :-)
Bill


[QUOTE=ramblinrod;2186331]This is kinda strange. You want to "anchor out" in a boat large enough to need a windlass (heavy anchor and chain), and yet all you have is a single "car battery" (assumed starting battery) to power all boat systems?

[anacapaisland42]

PS: I see you have a Douglas 32......a fine boat!!
Bill

[QUOTE=ramblinrod;2186331]This is kinda strange.

[zstine]

Originally Posted by ramblinrod

This is kinda strange. You want to "anchor out" in a boat large enough to need a windlass (heavy anchor and chain), and yet all you have is a single "car battery" (assumed starting battery) to power all boat systems?
. . . .
You can do as you wish on your boat of course, but the combination of elements in your request is a strange mix for sure.

So the reason I did it on my '75 Tartan 41 was primarily ease of install and secondarily save money. My house bank (3 LA's) are aft near the engine. If I tried powering the windlass off it direct, I would have had to install 00awg wire, 70ft round trip, which if marine tinned wire, would have been like $400. So i added a separate battery under the V-berth. To charge that off the engine I would have needed to add a battery isolator ($100) to charge the windlass battery and the house bank together, then run medium gauge (4 or 6awg?) wire from aft all the way forward.. i may still do that, but for now, the solar charging is easier. And only needing to run heavy cable 5ft is much cheaper and easier than a nice neat hidden install from aft.

[ramblinrod]

Originally Posted by zstine

So the reason I did it on my '75 Tartan 41 was primarily ease of install and secondarily save money. My house bank (3 LA's) are aft near the engine. If I tried powering the windlass off it direct, I would have had to install 00awg wire, 70ft round trip, which if marine tinned wire, would have been like $400. So i added a separate battery under the V-berth. To charge that off the engine I would have needed to add a battery isolator ($100) to charge the windlass battery and the house bank together, then run medium gauge (4 or 6awg?) wire from aft all the way forward.. i may still do that, but for now, the solar charging is easier. And only needing to run heavy cable 5ft is much cheaper and easier than a nice neat hidden install from aft.

Can't say for your particular case, but for most boats this size I evaluate, a dedicated windlass battery isn't warranted.

If the dedicated battery is in a non-ventilated space, and/or not adequately isolated from occupied space, it should be an AGM. AGMs don't have a lot of oomph for size, so a big AGM. A big AGM DC is around $300. Add in the short high current cables and connectors $50, the low current charging cables and connectors $50, the echo charger $125, and the box $25, you are up to $550, and now you have another battery in another location (likely difficult to access) to maintain.

In comparison, a 30ft red cable and 30ft black cable 2/0 (assuming 1000W windlass) and connectors $550.

Labour (whether hired or DIY) for dedicated battery install is higher as cables have to be run from house bank to windlass regardless (AWG doesn't really change labour). (An exception would be putting an AC charger forward to a nearby AC outlet, but this has it's own costs and issues.)

In addition, with the cables run to the house bank, you get the full benefit of the available charge current (alternator, solar, wind, DC generator, and/or AC generator and DC charger) to supply the windlass current demand and house bank recharging, whereas when using a dedicated battery with echo charger, recharging is limited to 15 A.

Prices used in Canadian dollars.

[mitiempo]

Originally Posted by ramblinrod

Can't say for your particular case, but for most boats this size I evaluate, a dedicated windlass battery isn't warranted.

If the dedicated battery is in a non-ventilated space, and/or not adequately isolated from occupied space, it should be an AGM. AGMs don't have a lot of oomph for size, so a big AGM. A big AGM DC is around $300. Add in the short high current cables and connectors $50, the low current charging cables and connectors $50, the echo charger $125, and the box $25, you are up to $550, and now you have another battery in another location (likely difficult to access) to maintain.

In comparison, a 30ft red cable and 30ft black cable 2/0 (assuming 1000W windlass) and connectors $550.

I agree with Rod.

In addition you only buy the cables once. The battery needs both maintenance and periodic replacement.