Are My Batteries Toast?

[john61ct]

Originally Posted by Paul L

Come on, you were the one that said that one of the key benefits of the SmartGauge gauge is that it didn't require futzing. Of course you could shut off loads and let things settle every time you wanted a reading from the smart instrument. I just wouldn't do that 3 or 4 times a day and neither would most users.
To each his own.

Obviously I'm not talking daily usage, but then I also don't need to know accurately many times per day, usage patterns become instinctive once you're familiar with a given setup.

My point is you (I) don't **need** an AH counting monitor to know when the bank's at rest.

There are cheap gauges available if your setup requires it.

[Paul L]

Originally Posted by john61ct

Obviously I'm not talking daily usage, but then I also don't need to know accurately many times per day, usage patterns become instinctive once you're familiar with a given setup.

My point is you (I) don't **need** an AH counting monitor to know when the bank's at rest.

There are cheap gauges available if your setup requires it.

Ok, you see great benefit in them, I'm skeptical. Fine enough, but I can't see how they are futz free if you can't just go to the unit and read it's dial and believe what it says.

[Stu Jackson]

Originally Posted by a64pilot

Yes, but right now all I know is my consumption is 15% of SOC overnight, but how many AH is that? Is my 660 AH bank a 600 or maybe even 500 AH bank? If can track somehow a good guess on capacity maybe ai can forecast when it needs replacing.
An issue is my inverter doesn't show any amps used until it exceeds 10. But of course say an 8 amp load constant is a lot, but maybe it's only drawing 1?

a64, You have a very good grasp of these issues and your discussions about AGMs are truly priceless and right on the mark.

Your energy budget, if done properly, will be easy to confirm. You will be noticeably pleased with how well you can guess what is going OUT of the house bank.

It's what's going back IN that is harder, and you have nailed that description, too.

Here are some things you may have already seen, maybe Ken hasn't.

Battery Acceptance by Stu Battery Acceptance

Record of Daily Energy Use of 100 ah per day:

"Breaking In" New Wet Cell Batteries

[Kenomac]

Originally Posted by Delfin

Just fyi, but if the batteries are older and starting to sulphate, equalizing them at high voltage causes the sulfate deposits to slough off the plates and if there is enough of it, it can pile up and short out a cell. In other words, equalization can make things worse on older banks.

How old are these batteries?

Five years old.

I don't know how much fun I'm going to be today, I've come down with the Norovirus bigtime. Must be all those cruise ships pulling into town daily.

[Kenomac]

I dragged myself over to the battery displays, it's been 38 hours since their last full charge and running the generator.

Smartgauge reads 62%

Magnetronic reads 75.1%

I almost wanna see if I can go three days without running the generator, but first I'm going try and keep this Zofran medication down.

[Kenomac]

Which is better for my batteries? One 1.5 hour generator charge in the morning then solar once every two days.

Or one 0.5-0.75 hour generator charge daily then solar.

[john61ct]

Getting to 100% Full is what is good.

If one day is very sunny the other not, or one high usage the other low, then the first example may be best.

Two days with the same conditions should use the second.

But if neither approach gets you to 100% Full, or causes your draw down to go lower than 50%, then it likely doesn't matter much, in reality too many variables to quantify the loss of lifetime cycles.

How many amps is the charger relative to the bank AH capacity?

For those Lifelines, I would say at least a .4C rate.

And you are equalizing monthly?

Sorry if already mentioned....

[Bleemus]

Originally Posted by Kenomac

I dragged myself over to the battery displays, it's been 38 hours since their last full charge and running the generator.

Smartgauge reads 62%

Magnetronic reads 75.1%

I almost wanna see if I can go three days without running the generator, but first I'm going try and keep this Zofran medication down.

If this were me I would assume I have the Magnetronic programmed to believe that my battery bank is healthier than it actually is. But thats just me.

[john61ct]

Strictly speaking, the every day approach does maximize AH absorbed, but only if the bank gets to a lower current rate within the doubled one-day timeframe.

Not if it is still in Bulk/CC phase for both scenarios.

But that is just about power availability, has nothing to do with longevity, which really does require the 100% Full, 98-99% is not "close enough", much less thinking 90% is healthier than 75%.

[Bleemus]

From Section 9 addendum in SG manual . . .

"Discharging is the important phase, as this is when one really needs to know the State of Charge. During charg-

ing this is not possible due to the presence of the charger preventing Smartgauge[emoji769] ever getting an opportunity

to actually measure the charge status. In effect, if it tried, it would be attempting to measure the charge status

of the charger. During charging, Smartgauge[emoji769] only shows the calculated charge status as does an amp hours

counter. However Smartgauge[emoji769], because it operates on a different principle, calculates a charge status that ismuch more accurate. For this reason, it is possible that, during the charge cycle, the charge status displayed may

not be totally accurate. It will be within 10% of the actual battery charge status.

(Note that once discharging commences, Smartgauge[emoji769] will automatically re-synchronize itself within the first

few minutes of discharge or within the first 10 minutes of resting if no load is present. Smartgauge[emoji769] uses this

information to modify its battery models and algorithm to increase the accuracy of future calculations)

Smartgauge[emoji769] will provide a dependable indication (certainly better than an amp hours counter – and certainly

better than a volt meter but it could be that Smartgauge[emoji769] shows the charge status to have reached (as a worst

case example) 100% when in actual fact the batteries have only reached 90%.

Not charging to 100% charge state is one of the most common reasons for premature battery failure."

In summary your Magnetronic is just guessing at SOC during the charging cycle just like the SG but the SG is more accurate. MaineSail was skeptical that this could be possible but his testing proved otherwise. Thats good enough for me.

[IdoraKeeper]

The empirical analysis of your battery bank is all good and well. It sounds like normal wear and tear under good upkeep. You use them alot. If the performance at this time bothers or hinders your operations, it's time for boat bucks. The same for the windlass. Not working right? Fix or replace. If it's useable as is, you are monitoring for catastrophic failure. Just be mindful of a failure in an inconvenient location.

[poiu]

Originally Posted by Kenomac

Yes, there was increasing noise and squealing when under tension, but we thought it was the pulley at the end of the boom, which we lubricated several times. Somehow the noise must have transfered down the mast and out to the tip of the boom (hollow aluminum), which fooled us. So yes, in hindsight if this turns out to be where the bearings came from, we had plenty of warning. But I won't know for sure until next Monday when help arrives and we drop the mainsail to examine the swivel.

Actually, it's not difficult to check on them, I just failed to clean and lube them anually when I did the others (staysail and yankee), an oversight on my part. When the halyard comes down with the sail, the swivel can then be easily reached and serviced at the gooseneck. I thought it had sealed bearings.

I had this happen. It turned out that after the swivel lost its balls it got revenge and cut through the foil partly and made furling really hard - the swivel jammed on the cracked bits. A trip up the mast when the sail is off will reveal any damage. I had to replace the top third of the foil. I think it's a good idea to inspect for damage. The fix was a new design, longer, tougher swivel, which I bought. Formula Spars will advise you. It's quite a big job if the foil is broken. I hope you don't have to deal with it.

[Pitchondesign]

I have been reading this thread with great interest. Almost all the cruisers I know follow the same charging regiment each day. Each boat is different, but whatever they do, it's the same each day. The reason for this is practical. You have only so much solar, so much generator/engine/charger capacity. The sun will shine only so much, and the wind will only blow so hard. What most want to know is will my batteries be good enough to last the season. Most have some type of battery monitoring, with the associated limitations of each method. As already stated it hard to know the charge capacity of batteries using in boat battery monitors. I have found the newer generation of external battery testers effective. Some thing like this

https://www.amazon.com/ANCEL-Profess...ds=ancel+ba101

It about $55 and shows state of charge and capacity. For best results the battery should be disconnected and close to full charge (90%+). I check my batteries every few months. It gives me plenty of time to spot a degrading battery and plan for a replacement.

We cruise 6 months every year mostly away from places where we could get a battery at a reasonable price.

[Kenomac]

Originally Posted by poiu

I had this happen. It turned out that after the swivel lost its balls it got revenge and cut through the foil partly and made furling really hard - the swivel jammed on the cracked bits. A trip up the mast when the sail is off will reveal any damage. I had to replace the top third of the foil. I think it's a good idea to inspect for damage. The fix was a new design, longer, tougher swivel, which I bought. Formula Spars will advise you. It's quite a big job if the foil is broken. I hope you don't have to deal with it.

At this point, do I need to go up the mast before I try to unfurl the sail to take it down? Is there something I can accomplish by doing this to minimize the damage? The company that makes the swivel is currently shut down for while.

[john61ct]

Originally Posted by Pitchondesign

I I have found the newer generation of external battery testers effective.

Color me skeptical wrt Bank Health, remaining 20-hour AH capacity after walkdown has become significant.

As with any method, establishing a benchmark when new gives a useful sense of things, can see deterioration begin to accelerate. . .

But unless one is **also** doing proper 20-hour load testing with different banks, a variety of bank types over many years, and comparing the results with the "quick and easy" tester, I will myself only rely on the former when an accurate AH rating number is important.