Battery Charge Readings ?

[sailorboy1]

don't really know what you are even talking about, I think we are talking different things

In fact I don't know for a fact how it is wired, just how the boat manual drawing has it because I've never pulled the start battery out,removed the back cover of the inverter switch, and looked to see what/where the wires are. But since all the cables going into the back of the switch are 1/0 or better I think we are talking different things.

The switch I'm talking about can take a LOT more than 5-10A, it supplies the freakin inverter and is the same switch that the charger would send power though to charge the batteries, it's an INVERTER/charger switch not a battery selector switch, the alternator ties into the same charger circuit as the inverter/charger and sends power to the same house bank as with the alternator as it would with the charger. The only thing that switch has to do with the alternator charger system is that the power from the alternator goes into it.

[twistedtree]

Originally Posted by Don Lucas

Don't take me wrong, I appreciate all the suggestions!!! I knew about a lot of these things already from when I spent time last year learning how the boat was wired.

But a lot of these are different issues than the one I'm currently trying to resolve, which is the battery capacity, charge and voltage issue.

Can I get any thoughts on whether my charges to the regulator programing were probably the source of my problem? To review I have:

1- changed the programing from the default universal to Deep Cycle FLA . Right off the bat this increased the bulk charge voltage from around 13.8-13.9 to 14.1-14.2.
2 - added 0.2V to the charge cycle voltages. So the bulk has gone to about 14.6 and absorption to 14.5. Float if I ever get there should be 13.8 because the FLA programing was 13.6.

And I bet the charge problem as always existed on the boat because this is at least the 3 set of batteries the 11 year boat has had.

Yes, I think that will likely fix your charge problem, or at least come very close. But you will still need to deal with the likely sulfation, assuming SG readings show the batteries still aren't fully charged even though the charger thinks they are based on voltage and absorption current.

[Maine Sail]

Originally Posted by Don Lucas

don't really know what you are even talking about, I think we are talking different things

In fact I don't know for a fact how it is wired, just how the boat manual drawing has it because I've never pulled the start battery out,removed the back cover of the inverter switch, and looked to see what/where the wires are. But since all the cables going into the back of the switch are 1/0 or better I think we are talking different things.

The switch I'm talking about can take a LOT more than 5-10A, it supplies the freakin inverter and is the same switch that the charger would send power though to charge the batteries, it's an INVERTER/charger switch not a battery selector switch, the alternator ties into the same charger circuit as the inverter/charger and sends power to the same house bank as with the alternator as it would with the charger. The only thing that switch has to do with the alternator charger system is that the power from the alternator goes into it.

Don,

All we can go off of is what you feed us. You show the alt output on an "F" terminal. The "F" terminal on a battery switch is to break the alternator field wire, this is a very low current wire and very low current handling circuit on a battery switch. The #1, #2 and "C" post can handle 100's of amps but the "F" terminal can not. Hopefully the alt is NOT in fact on the "F" terminal but you would need to tell us that if the drawing is wrong. I certainly hope that drawing is wrong..

[sailorboy1]

OK the drawing is wrong (I'm not looking at it again as I used the drawings in the manual to make that simple one)!

Otherwise every Hunter 410 that had an inverter and high output alternator, 100s of 410s, would have burned up. Along with probably 40.5s, 420s, 450s, 430s, 426s, etc because I bet they were basically the same electrical!

Basically the whole probem has been a Hunter issue. I should have know this to start with.

this went way off track!!!

Mainesail what is you input to the orginal problem with battery monitor readings and the actions taken as that is what the thread is about?

[Maine Sail]

Originally Posted by Don Lucas

Mainesail what is you input to the orginal problem with battery monitor readings and the actions taken as that is what the thread is about?

I have made a number of suggestions, none of which you are willing to accept....

Adjusting the voltage won't help your counting errors but will help the batteries charge slightly faster and more fully. Unfortunately you simply can't get effective recharging with only an alternator unless you want to run the motor for 10+ hours. If you are on a mooring your bank really needs solar, wind or another supplemental charging source or they will sulfate..

[twistedtree]

Originally Posted by Maine Sail

Unfortunately you simply can't get effective recharging with only an alternator unless you want to run the motor for 10+ hours. If you are on a mooring your bank really needs solar, wind or another supplemental charging source or they will sulfate..

+1 on that - I totally agree.

[Maine Sail]

Originally Posted by twistedtree

+1 on that - I totally agree.

We have about 1200 boats at the mooring field in Falmouth, ME and most of them are sailboats. Average battery life for boats without supplemental charging is abysmal compared to boats with solar or wind, especially with AGM's.

I know this because I am the guy replacing many of these batteries. Four Boats last week alone, a total of 14 batteries, and the oldest bank was four years & seven months old and two of them were Trojan banks. I have three boats to look at in the next three days all of them with "battery & charging issues".... Some of the cells in these batteries looked like a Chia Pet...

I advised solar to each customer and two are taking me up on it. Three of the boats had "gourmet" alternators and regulators but still had the batteries fail in just a few short years because they never got to full.....

One bank of three group 31 wet cells, was at just 10.6V when I got there. They were so sulfated that they were accepting just 3.8A of charge current from the 125A alternator.... They are still sitting on the floor of my shop for the next core charge run...

On boats with solar or wind I'm seeing 5, 6, 7+ years even with stock alternators. Getting batteries to 100% is simple and it involves TIME.... Solar on mooring sailed boats can do this cheaply and effectively, while you are not even there....

The other option is to buy cheap batteries and just replace them every three to four years...

[dandrews]

Originally Posted by Maine Sail

We have about 1200 boats at the mooring field in Falmouth, ME and most of them are sailboats. Average battery life for boats without supplemental charging is abysmal compared to boats with solar or wind, especially with AGM's.

I know this because I am the guy replacing many of these batteries. Four Boats last week alone, a total of 14 batteries, and the oldest bank was four years & seven months old and two of them were Trojan banks. I have three boats to look at in the next three days all of them with "battery & charging issues".... Some of the cells in these batteries looked like a Chia Pet...

I advised solar to each customer and two are taking me up on it. Three of the boats had "gourmet" alternators and regulators but still had the batteries fail in just a few short years because they never got to full.....

One bank of three group 31 wet cells, was at just 10.6V when I got there. They were so sulfated that they were accepting just 3.8A of charge current from the 125A alternator.... They are still sitting on the floor of my shop for the next core charge run...

On boats with solar or wind I'm seeing 5, 6, 7+ years even with stock alternators. Getting batteries to 100% is simple and it involves TIME.... Solar on mooring sailed boats can do this cheaply and effectively, while you are not even there....

The other option is to buy cheap batteries and just replace them every three to four years...

Maine Sail....on Don's 460ah house bank, what size solar are you recommending to your customers?

Thanks.

Don Andrews

[Maine Sail]

Originally Posted by dandrews

Maine Sail....on Don's 460ah house bank, what size solar are you recommending to your customers?

Thanks.

Don Andrews

Enough to get from 80% SOC to 100% as quickly as possible and as quickly is as feasible.. This always depends on real estate that is able to be devoted to panels. Most of these boaters can get their banks back to 80-85% with the alt so the solar is to top off the rest...

So 20%, or 80% SOC, of 460 Ah's = 92 Ah's needing replacement. At about 4.5 hours per day of full output, in Maine, and wanting to recharge in five days you'd need panels capable of about 5A+ output.

With a bimini or davits you can easily fit 135+ watts of panel. If mounting off the stern push pit you could do 40W port & starboard or one can also do flip up panels etc. etc... Any supplemental solar or charge source is better than just the alt for mooring sailed boats.....

[twistedtree]

The current to maintain float voltage can be C/100, or 4.6A in this case, so 5A will just hold the batteries on float. Personally, I'd shoot for something in the C/20 to C/50 range if it's possible to fit the panels. The 135W panel that MainSail is suggesting will produce about 10A @12V, so that's about C/50. More is better if you can find the space.

[dandrews]

Thanks, guys, great information.

Don Andrews

[Jbaffoh]

I'm having similar symptoms as Don--but with a twist:

I have 2 Trojan 145's (6v) on a 50-watt solar panel with PWM controller. The starter battery is isolated from the house bank, except for a Blue Seas ACR. I have a LinkPro monitor.

The batts are 18 months old. I checked open circuit voltage and SG a month ago. 12.74v and 1.280 on all cells. I haven't used the boat since then.

Today, I turned off the solar panel when the monitor said the batts were 99.8 percent SOG. I turned on all electronics to put it under an 8 amp load. Within 30 minutes, the main bank was down to 12.17v, and I was starting to feel nauseous.

But then it turned around! Still under the same constant load, the LinkPro is reading 12.31v 20 minutes after the lowest point, and it continues to climb. It's showing 98.1% capacity, with 5.1 ah used.

Why would voltage plummet, and then rebound, while continuing under the same load?

[sailorboy1]

Originally Posted by dandrews

Maine Sail....on Don's 460ah house bank, what size solar are you recommending to your customers?

Thanks.

Don Andrews

FWIW I already have figured I need around 260W of panels. You've been on my boat, where's lots of room to mount to the traveler bridge.

Maybe I would have gotten the panel this month or so, but I dropped some cash on the autopilot replacement and now I want a light wind sail.

everything on a boat can be corrected with the proper application of cash!

[dandrews]

Originally Posted by Don Lucas

FWIW I already have figured I need around 260W of panels. You've been on my boat, where's lots of room to mount to the traveler bridge.

Maybe I would have gotten the panel this month or so, but I dropped some cash on the autopilot replacement and now I want a light wind sail.

everything on a boat can be corrected with the proper application of cash!

LOL...yep know about the application of cash to address problems. I was looking off into the future for my Bristol. I will be using 6V batteries like you have and more than likely will put 4 units in. I have allowed space when I rebuilt the aft port quarter berth. As to where to mount some panels, am letting my brain work on that issue now.

Don Andrews

[btrayfors]

Originally Posted by Jbaffoh

........

Why would voltage plummet, and then rebound, while continuing under the same load?

That's very typical of flooded batteries.

Consider this graph showing three banks of golf cart batteries. The two on the top are 11-year old gels.

The third bank consists of two Trojan T-105s which are about five years old. The red curve shows the performance under load of this bank which has been under "pulser" treatment for several months.



The blue curve shows the same bank which has been equalized one time only.

You can easily see that the equalization made a difference.

You can also see that it is very typical for flooded batteries under a constant load to show a voltage dip, then a recovery.

This graph shows only the first 20 minutes under load. The "recovery", though, lasts a long time; it's not just transient. That is, voltage remains at the higher level for some time.

Bill