Battery Craziness

[colemj]

Originally Posted by Maine Sail

rare emergency, run off the start/reserve bank until you sort out the bad battery. Flip a switch and you are back in business, now go find the problem and isolate it.

Our house batteries are all on individual cutoff switches. If one (actually 2 6V) goes bad, just turn its switch and isolate it.

Mark

[donradcliffe]

I've said it before and I'll say it again--you're better off mixing battery types than having 2 banks

[noelex 77]

Originally Posted by donradcliffe

I've said it before and I'll say it again--you're better off mixing battery types than having 2 banks

So if you had say 2 gel batteries and 2 flooded LA batteries in two separate banks you would leave them coupled and paralleled all the time?

Why not at least separate them to give the flooded batteries an occasional higher charge voltage. This would give the flooded batteries a longer life than continually charging to the much lower safe gel limit.

I am just trying to understand if you could separate them with the flick of switch why you would not do so at least in some circumstances.

I wanted to get the question in before the donkey died

[skipmac]

Originally Posted by Canibul

Interesting comment, as I continue to redesign what I inherited here. would be interestedd in thoughts on best way to power an electric windlass. do you run heavy cables all the way forward, or do you put a small 12 volt battery in the bow next to the motor and run trickle charge forward?

I have seen it done both ways. Personally I like the simplicity of wiring and charging to run large cable forward to the windlass. You will need to run large IE expensive cables, to avoid too much voltage drop (bad for a windlass motor that has to work hard) but I much prefer this method. Just run two large cables.

- Don't have to install battery, box, strap it down
- And run charging wires to the battery
- And still have to run cables from battery to the windlass
- Have no heavy battery in the bow (yes you will have similar overall weight added to the boat with the large cables but not all in the bow)
- And one less battery to maintain and replace, to worry about acid leaks, etc.


This assumes you have reasonable access for running the cables to the bow.

[Canibul]

the weight of a battery in our bow is of no consequence. since a windlass is used so seldom , how about a battery with a small solar panel to keep it charged? No cables running forward at all?

Part of my thinking here is that since I just put in four new six volt batteries, I think I'd feel a little better if I had a 12 volt somewhere on the boat. Could be the cheapest car battery in the shop. Who cares. But it'd be enough to jump our little diesels if needed.

[Jim Cate]

Originally Posted by Canibul

the weight of a battery in our bow is of no consequence. since a windlass is used so seldom , how about a battery with a small solar panel to keep it charged? No cables running forward at all?

Part of my thinking here is that since I just put in four new six volt batteries, I think I'd feel a little better if I had a 12 volt somewhere on the boat. Could be the cheapest car battery in the shop. Who cares. But it'd be enough to jump our little diesels if needed.

I think that you are underestimating the power usage of the windlass, and overestimating the charging capability of a tiny solar panel.

There have been times when we have had to up anchor several times in a row due to patchy bottom conditions, and this in pretty deep water. Your small cheap car battery would be hard pressed to cope with that without considerable voltage drop, and that isn't good for the windlass motor. Now, if that happened after several cloudy days...

It's an expense and a nuisance to run the big cables forward, but being able to supply the windlass directly from the alternator in the event of dedicated battery failure or discharge can save your bacon.

Cheers,

Jim

[Ex-Calif]

Originally Posted by Canibul

the weight of a battery in our bow is of no consequence. since a windlass is used so seldom , how about a battery with a small solar panel to keep it charged? No cables running forward at all?

Part of my thinking here is that since I just put in four new six volt batteries, I think I'd feel a little better if I had a 12 volt somewhere on the boat. Could be the cheapest car battery in the shop. Who cares. But it'd be enough to jump our little diesels if needed.

What are you doing now? If it's working I wouldn't mess with it.

For me this is about being able to apply maximum amps from the "whole" electrical system for as long as the windlass needs it. I'd estimate when it is in use it is the highest power draw on the boat.

I have never seen anyone or personally used a windlass unless the engine or boat generator was running. I don't know what yours draws but at stall load it is not unusual to approach 300 amps! Of course that is only momentary and a 5-10 minute duty cycle at running load is probably more like 80amps - but even 80 amps is a ton.

I like 70 amps coming from the alternator to help out.

E.g. - My brothers boat is similar length - He has a generator but I think gets like 70 amps from the alternator on the engine.

Also if the engine can't or won't run - I'd like every battery on the boat to be able to help out if I need it.

Originally Posted by Jim Cate

I think that you are underestimating the power usage of the windlass, and overestimating the charging capability of a tiny solar panel.

There have been times when we have had to up anchor several times in a row due to patchy bottom conditions, and this in pretty deep water. Your small cheap car battery would be hard pressed to cope with that without considerable voltage drop, and that isn't good for the windlass motor. Now, if that happened after several cloudy days...

It's an expense and a nuisance to run the big cables forward, but being able to supply the windlass directly from the alternator in the event of dedicated battery failure or discharge can save your bacon.

Cheers,

Jim

I don't think it's a "big" expense issue - compared to buying a battery and installing a charge system for it.

Another reason to not rely on solar to top this up is you normally anchor at the end of the day - do couple of drop due to sketchy bottom. Then the sun sets - right after you discharged, then it blows up over night and you find you aren't as sheltered as you thought and you need to do another couple of drops. Oh, and I wanna leave at first light...

May not be the best solution.

At your length I think you can run battery cables from the house - Get into the 50+ range and forward batteries start making sense to me. Actually what starts making sense is a boat designed with battery storage forward of the engine and aft of the bow - i.e somewhere amidships. From a power distribution standpoint it makes things easier in my mind.

[Canibul]

We don't have the same anchoring issues you have in the PNW. We anchor in less than 10 ft of water, sometimes as little as 4 ft. It's not like we're pulling 200 ft. of chain out of the Pacific.

We presently have a manual windlass on board, I forget the brand, a Simpson hyphenated something or other. But we also got an uninstalled electric windlass with the boat. THe manual windlass has been a problem every single time we used it. I've had it apart twice, packed it in grease, made a new gasket and stainless bottom plate for it, etc. Nothing wrong with it, it operates as designed. Too much physical involvement for La Gringa, and I'm worried she's going to lose a finger trying to get this anchor down. We have a huge chain locker and plenty of room for another windlass alongside the manual one. Running heavy cables would be a lot more trouble than running a couple small wires to trickle charge.

[Ex-Calif]

Originally Posted by Canibul

We don't have the same anchoring issues you have in the PNW. We anchor in less than 10 ft of water, sometimes as little as 4 ft. It's not like we're pulling 200 ft. of chain out of the Pacific.

We presently have a manual windlass on board, I forget the brand, a Simpson hyphenated something or other. But we also got an uninstalled electric windlass with the boat. THe manual windlass has been a problem every single time we used it. I've had it apart twice, packed it in grease, made a new gasket and stainless bottom plate for it, etc. Nothing wrong with it, it operates as designed. Too much physical involvement for La Gringa, and I'm worried she's going to lose a finger trying to get this anchor down. We have a huge chain locker and plenty of room for another windlass alongside the manual one. Running heavy cables would be a lot more trouble than running a couple small wires to trickle charge.

What about putting in an ACR circuit?

[Canibul]

well, there's DC all over the place up there now, with running lights etc. I was thinking of somehow using that.

I normally pull the anchor by hand. Including the 50 ft. chain. She can't do that.

[Ex-Calif]

Originally Posted by Canibul

well, there's DC all over the place up there now, with running lights etc. I was thinking of somehow using that.

I normally pull the anchor by hand. Including the 50 ft. chain. She can't do that.

In simple terms none of that is gonna work, probably.

See the battery up there is blind and thirsty. anything connected to that battery is gonna need to be current limited or heavy gauge.

When you hit the button the windlass (hence battery) is gonna ask for 80 amps if you have anything hooked up with access to that much power it's gonna try to push itself down that wire.

Now - out of the box - If there was a device that could use like 14 gauge wire and was current limited/regulated to like 5 amps you might be able to use some wires that are already there to suck juice from the house. Then you could charge anytime from the house. Albeit when the machine is running you only get a 5 amp assist. Look at the numbers and you might be able to push it to 10 amps.

There may be a DC regulator out there already or it might be a radio shack project...

edit - OK - I'm a bit OCD so I googled it. On page 4 of this article they talk about how they can make a 5 amp current limited charger with all their elektrickery. Honestly it goes into Latin pretty quick for me and they do say something about frying diodes with load spikes etc...

http://www.vicorpower.com/files/live...antCurrent.pdf

[crazyoldboatguy]

Is it possible/logical to run ac power up there to an inverter/charger/battery so as to avoid thick cable runs? I am not 'lectric savvy. I have seen those car battery chargers w/boost capacity for actual "jumping" ability. I don't know how many amps it will provide or for how long.

I like the idea of placing batts midships to reduce cable runs. That might be a better way to get power to a windlass on our 48' boat.

[Cheechako]

Originally Posted by sailorboy1

Batteries aren't made of gold, even though we seem to talk about them like they are. So much obsessing over what in the bigger picture are inexpensive regular replacement required items.

I got my current set of 460AH house batteries for about $440 (6V golf cart batteries). To “protect” them I got a battery monitor for $170. Then to recharge them out on the mooring I spent $1600 on a solar setup. Granted the solar was also part of a cold beer project and I could have gotten a 100W panel to recharge the batteries from weekend use for probably $800 total project.

So let’s say that between the Battery Monitor and the cheaper solar it would be $970 to “protect” the batteries. All to get say 5 years instead of 3 years life out of the batteries. At 5 years life the cost of the batteries is $88/yr and at 3 it is $147 (rounded) for a yearly savings of $59. So to save $59/yr you spend $970, which is a 16 year pay back (if your batteries were/are lasting longer the payback gets even longer)

Does this make boaters cheap or just crazy?

Let’s stop obsessing about these stupid batteries so much!

[Cheechako]

There used to be a place in Seattle called... DYNA?... who made their own batteries. They had cut up examples of their and other batteries. Life of batteries is all about the thickness of the plates (as well as proper use!) The plates give up lead over time... so the thicker ones last longer. Their batteries were cheap..... and thicker plates than any others on display.
If you want the best battery for the buck take your digital bathroom scale and go around and weigh them.

[pbmaise]

Solar panels have come down in price so much battery banks should be sized based on:

#1 House bank - Enough to start engine

#2 Engine bank. Enough to start engine

Anything more is a waste of money and extra weight.

The reason is the refrigerator will stay cold overnight provided you have it well insulated and dont open every 5 seconds.

Solar regulators are a waste of money. If you yourself are not there to check and prevent batteries from overloading simply insert a voltage cutoff switch that shuts a solar off.

Use a similar voltage cutoff switch that allows the fridge to run when there is enough solar power.