AC charger smarter than the 3 stage "smart" charger?

[btrayfors]

Don't forget to check the location and wiring of the isolator. This could be the problem if the alternator charging current goes through the isolator, but the battery charger doesn't.

Bill

[Pblais]

I have to do a bit more testing to know, but I have seen what the CSY man sees with my former 1989 "smart" regualtor and now have a new balmer Max Charge regualtor. The Sentry shore power charger has just been recalibrated for the new batteries so I should be able to tell if it works any different.

My past experience says you can motor all day and not always get back that last 50 or 60 amp hours as measured by my Link 10. A day or so on the solar panel (1 - 75 watt) generally tops it off at the end of the trip.

[ssullivan]

What Bill says here kind of goes along with my guess. If each individual charging current goes through different paths and encounters different electronics along the way before getting to the battery, they might be seeing different things. One might see the battery as full, while the other sees it as needing another 60AH.

I wouldn't mess with the system if it's working for you either.... Like you said: "if it ain't broke, don't fix it" Your batteries charge, right? You are at a dock frequently, right? You aren't always charging up by motoring, right? Well you're all set then.

Originally Posted by btrayfors

Don't forget to check the location and wiring of the isolator. This could be the problem if the alternator charging current goes through the isolator, but the battery charger doesn't.

Bill

[coot]

Originally Posted by CSY Man

From the Xantrex Battery Monitor mentioned above.
http://www.xantrex.com/web/id/96/p/1/pt/5/product.asp

It is the "new and improved" version of the Link 10 and will give you detailed info on how many amps are being taken out and how many amps are being added to yer battery banks.

I downloaded the manual at that link. I don't see where it shows how many AH are being put IN to your battery, so I suppose the documentation just sucks.

How does this unit display amp-hours that have been put in? Does the "AH" display show a negative number of amp-hours removed from the battery? Does the "state of charge" go above 100%?

I'm still not sure I follow exactly what happened, including what indicators you looked at and what they displayed at each time. For example, while you were motoring, did you see the "state of charge' go to 100%?

I have one speculation, though: If the device shows AH that have been put in to the battery, I have to wonder if that number was 0 when you plugged in the shore power. If it is a cumulative value, it could have been 59 AH provided by the engine alternator and 1 AH provided by the shore power charger. (As far as I can tell from the manual, the battery monitor doesn't know the difference.)

[CSY Man]

Does the "AH" display show a negative number of amp-hours removed from the battery? Does the "state of charge" go above 100%?

Yes and no.

It shows how many amp/hours are being drained/removed, both in AH and %.

On the way back in (up) it only goes to 100% on one page, but continues up with the AH up, especailly since I "zero" out the display once it reaches 100%.

Kind of hard to explain if ya don't have a similar device.

I was indeed sceptical to this Monitoring gizzmo before I installed it, and had no desire for one, untill I friend bought one and shipped to me 'cause I looked after his boat during hurricane Katrina and Wilma.

To me it was a free-bee and not on my shopping list.
That beind said, now I love it and see much more detailed stuff on what is going on, hence this thread.

I downloaded the manual at that link. I don't see where it shows how many AH are being put IN to your battery, so I suppose the documentation just sucks.

Well, the documentation was fairly good, incuding the 20 step programming set-up.

Once ya try the thing, it all makes sense.

(Almost like reading about having sex before ya try it)

So, uh nothing wrong about the Xantrex Battery Monitor, after 10 months I love it and would not leave the dock without it.

I'm still not sure I follow exactly what happened, including what indicators you looked at and what they displayed at each time. For example, while you were motoring, did you see the "state of charge' go to 100%?

Yes.

I have one speculation, though: If the device shows AH that have been put in to the battery, I have to wonder if that number was 0 when you plugged in the shore power.

No.

This is not about the operator reading wrong, or the monitoring device displaying the wrong value.

You may be barking up the wrong tree on this one.

The basic question is: Why does one regulator pump more amp/hours into the bank than another?

[coot]

Originally Posted by CSY Man

It shows how many amp/hours are being drained/removed, both in AH and %.

On the way back in (up) it only goes to 100% on one page, but continues up with the AH up, especailly since I "zero" out the display once it reaches 100%.

My AH meter does not show a percentage - it only shows an approximation of how many AH are available in the battery. Because it is (and only can be) an approximation, I don't take the AH number as a literal truth.

I know my batteries are full when the charge current goes to 0. Sometimes, the charge current goes to 0 before the AH gets to 840. In that case, I reset it to full. If the AH indication gets to 840, but the charge current is still positive, I know the batteries are not really full, so I let the charger go until the charge current drops to 0.

The "%" display on your meter is the same thing, but divided out to show percentage instead of amp-hours. We know this is just an approximation, so it doesn't surprise me much that it may say "100%" even though the battery is not full.

This is not about the operator reading wrong, or the monitoring device displaying the wrong value.

You may be barking up the wrong tree on this one.

The basic question is: Why does one regulator pump more amp/hours into the bank than another?

It isn't about the operator or device being correct. It is about understanding what the information you got from the device is telling us.

At this point, I suspect that your engine charging system may be stopping before the battery is fully charged. I don't see enough information posted here to prove that is the case, though.

Before you start trying to fix anything, I suggest the next step is to try to make it happen again.

When you do, make careful notes of all the values that the meter can tell you. e.g. Before you start charging, note Volts, Amps, Amp-hours in battery, and Amp-hours added to battery. Note those values right after you turn on a charging source, periodically while it is charging, and then again a few minutes after you turn off the charger. If you then let the batteries sit, it wouldn't hurt to note the values again every hour or so. Don't reset any of the counters, but if you do, note when.

Ordinarily, nobody would keep that kind of record, but now that you are wondering what is going on, it would be worth it for a while.

The point of all this is to gather detailed information about how the system is misbehaving. For example, differences in the maximum voltage you see from the different chargers may be a useful clue, but you can only know if you collect that data.

[Vasco]

Originally Posted by coot

Before you start trying to fix anything, I suggest the next step is to try to make it happen again.

When you do, make careful notes of all the values that the meter can tell you. e.g. Before you start charging, note Volts, Amps, Amp-hours in battery, and Amp-hours added to battery. Note those values right after you turn on a charging source, periodically while it is charging, and then again a few minutes after you turn off the charger. If you then let the batteries sit, it wouldn't hurt to note the values again every hour or so. Don't reset any of the counters, but if you do, note when.

Ordinarily, nobody would keep that kind of record, but now that you are wondering what is going on, it would be worth it for a while.

Good advice. When I suspected that the Link might not be giving accurate data (Link showed very few amps used but the voltage was too low for such slight usage) I did this every day and found out that, if used with wind or solar charging in conjunction with charging via engine or generator and battery charger, it can reset to zero when you're still down a lot of amps. The Link's main advantage is it tells you amps being used and when charging, the rate of charge, other than that it seems to be a fancy volt meter. The tests it is capable of doing aren't very meaningful to a cruiser as in most cases it requires the batteries to be at rest for a considerable period (when are you going to do this?) or the batteries to be depleted at a certain rate.

[btrayfors]

Rick I raises a very good point, "The tests it [the Link] is capable of doing aren't very meaningful to a cruiser as in most cases it requires the batteries to be at rest for a considerable period (when are you going to do this?) or the batteries to be depleted at a certain rate."

Rated capacity of a battery bank in amp-hours (AH) can be deceiving.

Pop quiz:

Assume you have a battery bank consisting of two T-105 Trojan golf-cart batteries in series, rated at 225AH at 12 volts.

1. Is it possible to deplete those batteries by taking out a lot LESS than 225AH?

2. Is it possible to get a lot MORE than 225AH from those batteries?

If you answered, "yes" to both questions, you're RIGHT! The number of AH you can get out of a given battery bank depends on HOW MUCH LOAD IS CONNECTED AND FOR HOW LONG. Here are some illustrative numbers for the T-105s, based on Peukert's Exponent using 225AH for the 20-hour rate and 477 minutes reserve capacity...

Hours - Amps - AH

001 - 126.8 - 126.8
005 - 034.5 - 172.6
010 - 019.7 - 197.0
015 - 014.2 - 213.0
020 - 011.3 - 225.0
030 - 008.1 - 243.2
050 - 005.4 - 268.1
075 - 003.9 - 289.8
100 - 003.1 - 306.2
200 - 001.7 - 349.6
400 - 001.0 - 399.2

(Sorry for the leading zeros...only way I know to get the **!!!@@@*xxx table to format correctly :-)

Sooo, is the Trojan T-105 a 225AH battery? Or is it a 400AH battery? Or is it, perhaps, only a 125AH battery?

Yes, it can be all three, depending on load.

Ain't this battery stuff fun? :-))

Bill

[hellosailor]

Bill, I don't know if the Link does it, but IIRC at least one of the monitors out there is supposed to use Peukert's to generate more accurate numbers. From a programming point of view I guess that would actually be simple, just take the power consumption rate (in amps) and do a fast lookup on a table based on the battery bank capacity to grab a correction factor. "Trivial" programming, once you have that little extra memory and CPU power to do the job.

I guess the question is...which monitors do that job, and just how well they do it.<G>

[Vasco]

hellosailor,

The Link does do this but if I remember right (the manual is on the boat in FL and I'm in Toronto) you have to deplete the batteries at a constant rate to get the correct factor for your batteries.

[Pblais]

The Link 10manual has the common values for several batteries. The trick is that over time your batteries change so to keep the values accurate you need to tweak it. That is the hard part. For me getting close is enough. The very first long cruise we did on our boat ended on the last morning on the hook with some dificulty staring the engine. We retruned home and the next time I turned the key. 6 Trojan 105's could turn over the engine. The volts were right but there were not enough amps left. The whole set of three banks was shot after about 8 years of use. The Link 10 went in with the new batteries.

[CSY Man]

Thanks for all the replies and heplful tips..

Before you start trying to fix anything, I suggest the next step is to try to make it happen again.

No, going to tear into stuff and "fix it":

In other words, I am not sure it is broken, and I hestitate to fix it....

As for duplicating the situation:
Yeah not hard to do, every time I run the (AC) battery charger for a few hours, it pumps more amps in that I took out, by a wide margin, not just the 20% that is "normal".

When all else fail, read the book.
Which I did today: The Owners Manual for the Xantrex AC charger...It says if ya have the wrong temprature setting on the charger, it could overcharge the batteries.
Hmmm..., perhaps that is what we have been seeing?

Switched the button from WARM to HOT..That should limit the voltage going in and the total charge (Me thinks.)

Will let that sit for a while and see what shakes out.

The next step is to Equalize the house bank. Have not done since I installed the new batteries a year ago.
Perhaps they don't hold the charge as good anymore and they need a boost to get back up to speed?

Will take this trouble shooting slow and easy, not going to tear into stuff to "fix" it....

[btrayfors]

Have you figured out where that pesky isolator is, yet?

[CSY Man]

Have you figured out where that pesky isolator is, yet?

Yeah, it is down there somewhere under the Nav table seat isolating the start and house bank.

Have always know the location, just could not remember the wireing the other day as my brain and liver was full of Bitburger beer. (Highly recommended if ya are trying to forget something..Like the beauty queen ya picked up at Sleeazy Joe's Place at 2AM last night.. )

The AC charger is not going over the isolator, but the alternator's regulator is, and I also hooked the solar panels into the house bank side of the isolator so as to save on running wires in parallel to the house bank which is next the mast.

As a result, when the sun is shining and the engine is running, the RPM indicators stops working as the alternator is not putting out due to full batteries. That should not affect the input of the alternator on a cloudy day, or the AC charger's input however...Just a secondary effect of strong sun and fully charged batteries with the engine running.

Keep the input coming, all ideas are much appreciated.

[soul searcher]

Csy,
Im having a simular problem with an ample power monitor. I think it has to do with the solar panels. As near as I can tell so far in my search is that the monitor is suppossed to reset its values when it detects a 100 prc charge. start counting amps out again. If the panels are putting out It may be that the monitor is seeing the voltage of the panels and assuming the batteries are full and going in to float to soon on the alternator regulater. The only way it sees the panels is in a reduced amp draw when you have a draw. so in my case Im leaning toward the idea that since the monitor doesnt see what the pannels are putting in only keeps track of the draw it guesses based on voltage and the data you entered that the batts are full. when they arent or my house bank is shot. I got the start batts fully charged and and diconected them for 24 hour and got 12.8 volts I havent had the time to do the same with the house bank yet. I drew them down a long way !!.8 volts over a five day trip they are now full the monitor has been reset and hopefully this weekend I will be able to determine their health. If their up to snuff then I have figure out why the monitor is showig the data that it is. It says Im full after chargeing but my amps consumed would be enough to kill a single group31 but not two 8ds. so Im thinking that the 100prc reading may be in error .
god forbid I should get bored!

Matt