Yahoo Message Number: 11436 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11436)
My AGM batteries have performed flawlessly for 2 years and I hope to get 2 or 3 more years out of them. After having used them for 2 years, I'm wondering should AGMs should be equalized or not?
If you have accurate information from a reliable source on this subject, I would appreciate it if you could share what facts you know.
Regards,
Bob Kumza
Intrigue #11581
Yahoo Message Number: 11437 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11437)
I have ben told no...it generates to much heat..
Yahoo Message Number: 11439 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11439)
If you call Lifeline they will give you the info needed. Lifeline told me to equalize the AGM batteries. The confusion is created because Xantrex says not to. But, Xantrex does not make the battery, Lifeline does. You must be there during the the process. I have done it several times. Dale Hollick Affinity #6370
Yahoo Message Number: 11440 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11440)
I don't think so Bob. Lead acid batteries tend to build up sulfate on the lead veins in each cell. Equalizing is a way to boil sulphate off and rejuvenate them if they metal isn't pitted to bad. You increase the charge voltage on lead acid to like 16v and the batteries gas for a while.
AGM don't have a venting as they are entirely sealed so, I don't beleive you ca do that with them.
But, check with the mfgr.
Skip
======
My AGM batteries have performed flawlessly for 2 years and I hope to get 2 or 3 more years out of them. After having used them for 2 years, I'm wondering should AGMs should be equalized or not? If you have accurate information from a reliable source on this subject, I would appreciate it if you could share what facts you know. Bob Kumza
Yahoo Message Number: 11448 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11448)
Like a number of others here, my AGMs have not been holding a charge for very long, and lately, not at all. I talked with Lifeline, and he said he thought that equalizing them would solve the problem. It was an eight hour process, and by holding the right-arrow on the RC7GS for 6 seconds, it goes into equalizing mode.
Since we were leaving for Arizona at the time, I ran the generator for 8 hours as we drove. By the way, my RC7 kicks out of equalizing mode after 3 hours, so you have to re-do the 6 second thing to put it back in. After 8 hours, turning off the gen, or unplugging/plugging back in shore power, if that is how you are powering the equalizing, stops the process.
In my case, it did not help at all, my batteries are DOA.
I have to have them replaced here in Phoenix, at Copperstate Batteries.
Bill Harris
03 Allure 30912
Yahoo Message Number: 11449 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11449)
Dale:
Did you do it through the Silverleaf? Lifeline said to do it for 8 hours.
Mine seems to drop back to 13.6V in about an hour.
We have Magna 630 Number 6382 and the AGMs will not hold a charge. They float at about 13.6V but turn off the charger and they are at 12V (with the chasis battery switch off) and within 20 minutes 11.8V and the gen set starts. it is an all electric coach. I think the batteries are toast.
Any ideas?
John Drebick 05 magna 6382
Yahoo Message Number: 11453 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11453)
Hello to all
We have done extensive testing with this battery problem on our coach as we were initially having the same problem- premature gen start, earlier than what we knew it should have been with the battery bank capacity and the amount of load we were using. After extensive research, testing, and numerous conversations with CC and Silverleaf, the problem with the premature gen start is not that the batteries are bad (although if you keep equalizing them too much they will be!) but that the Silverleaf total coach system and VMS is not getting accurate battery voltage information.
The Silverleaf gets its information on battery voltage from the inverter, not directly from the batteries. Under a light load (just lights, for example) the difference between the voltage Silverleaf "sees" and the actual battery voltage measure at the battery bank is about 0.2-0,4 V less than actual. However, under heavier loads, such as when using the microwave, a coffee pot, toaster, etc, the difference between the two can be as much as 1.2 volt!
In other words, the Silverleaf may "think" the batteries have dropped to 11.0 volts (which would be a nearly totally dead battery) but the battery voltage is actually 12.0 or higher. The generator does not need to start at all.
We have Affinity 6400 and we had an additional two house batteries installed so that we calculated could get probably 18-20 hours of normal use without the generator coming on. We were experiencing genstart after about 10 hours of low overnight use when we began to use kitchen appliances in the morning. We knew there was no way with 1500 amp hours of battery capacity that the batteries needed to recharge after such minimal usage. So we did the following:
After knowing we had a full charge on the batteries, we unplugged from 50 amp and measured the voltage at the batteries at 12.67. The Silverleaf said the battery voltage was 12.0. Then we started the coffee pot, toaster and microwave. The Silverleaf fell immediately to 11.5, which would have started the generator except we had disabled it. However, the actual battery voltage was 12.32. In fact, during this five minute period, the Silverleaf went as low as 11.3, but the actual never went below 12.32, and generally was in the 12.45 range. As soon as all the appliances were turned off, the actual voltage went back up to 12.67 and the Silverleaf went back up to 11.8.
Country Coach and Silverleaf are very aware of this problem, and a fix is available. Silverleaf can modify their system to read the battery voltage directly from the battery instead of the inverter with just a different connection and a minor software update. If enough of us complain often enough, they will get busy and solve the problem. You need to measure your battery voltage with a volt meter at the batteries and compare this to the Silverleaf readings under light and heavy loads, and write it down and report it to Country Coach and to Cory at Silverleaf. Complain loudly!
Since the generator is the single item which requires the most frequent regular maintenance on the coach, I certainly don't want mine to run any unnecessary hours!
John Lewellyn
Affinity 6400
Yahoo Message Number: 11456 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11456)
John, I havent equalized the batteries on this coach.
Lifeline told me to do that on my 02 Affinity. It should only be done once every 12 to 18 months. What is yous new coach #? Your batteries are under full warranty, have them replaced AFTER doing what John L. suggested. I am going to check mine also. Dale Hollick (at the factory for service)
Yahoo Message Number: 11459 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11459)
John,
Has your Silverleaf TCS system been fixed? If so, can you provide an update on how the voltage readings are now. I have never heard of a battery monitor not running a shunt to the battery bank and instead going to the inverter to find the battery voltage. I assume you have an 05 Affinity?
Barry
Yahoo Message Number: 11460 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11460)
Barry-
No, it is not fixed, because Country Coach is not really addressing the issue. Actually, there is not really anything "broken" in the TCS-- it is just getting bad data. The TCS plugs into the Xantrex inverter via a "telephone jack" on the inverter. Xantrex tells me that their metering of voltage through this jack is not very accurate and not a good way for TCS to get its data. Also, the TCS software only looks at the voltage for 15 seconds before making a determination on whether to start the generator. With such a large battery bank, it is more usual in the industry for there to be a 10 minute delay before starting the generator due to low voltage.
In short, there are two problems going on. First is the bad data the TCS is receiving from the inverter. Second is the TCS software, which looks for only 15 seconds instead of the usual ten minutes before starting the generator. If more of us would complain to CC, instead of just one or two of us who have addressed this with them, I think we could get a resolution.
John Lewellyn
05 Affinity #6400
Yahoo Message Number: 11462 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11462)
John,
When I questioned Silverleaf earlier this year on how they measured current usage, etc. on an all electric Magna/Affinity, I didn't receive the detailed answers that I expected. Since I was also interested in the glass dash, they said I could see one when I came out to take a factory tour. But when I arrived in Junction City, I was told by Silverleaf I needed to make an appointment months in advance to drive up and see their products.
Barry
Yahoo Message Number: 11463 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11463)
Barry-
I don't have the digital dash. They measure current by means of rings inside the Surgeguard transfer switch and the output from the transfer switch passes through these current-measuring rings. The communication port in the Surgeguard has a port which allows the transfer switch to communicate to the Silverleaf TCS. As for seeing their office, there's not much to see. They don't manufacture anything
Yahoo Message Number: 11466 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11466)
Hi Guys,
I think it would be in the best interests of all the members that threads be limited to say 3 responses. After that go directly to the person or persons you are communicating with. Much of this information has been covered in the 2000-6000s messages. Get out your two binders and schematics especially the big foldouts and do some research first.
Tell us the solution rather than giving us a blow-by-blow account - we've been through it.
About 50% of the treads contain misinformation.
Joe
Yahoo Message Number: 11467 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11467)
Ha-ha! You'd get blasted for a post like this on the usenet newgroups where bandwidth means nothing! As far as they're concerned every post should contain the entire history of the original post with the most current response at the bottom - or you get your head handed to you!
Interesting on how the different presentation board audiences feel!
Dave
Yahoo Message Number: 11492 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11492)
You do not need to equalize any battery as long as you do not run them down and you take good care of them. We have never equalized any battery and we get about 4 years out of the standard CCI battery. I think equilizing batteries is dangerious and I will not do it to gain a little battery life, when the proper battery care will do the same thing.
Bill G. 2005 Magna #6425
Yahoo Message Number: 11497 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11497)
IMHO it isn't any more dangerous than filling your gas tank.... in fact less dangerous as long as care is taken to insure the compartment door is open so venting can occur. Just like at the gas pump you need to be around to shut the equalize process off after a few hours. Most control panels have the setting to equalize and if it were dangerous I doubt the mfgr would place themselves at such a high risk if were dangerous.
Over time .... all batteries can benefit from equalizing to get the sulphate build up off the plates. Less use extends the time they could use equalizing. The extended life when equalizing can be doubled or more... again, depending on use. Golf cart batteries are designed to be run down and used if you don't .... you could use the typical 12v auto batteries.
Skip
==========
You do not need to equalize any battery as long as you do not run them down and you take good care of them. We have never equalized any battery and we get about 4 years out of the standard CCI battery. I think equilizing batteries is dangerious and I will not do it to gain a little battery life, when the proper battery care will do the same thing.
Yahoo Message Number: 11503 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11503)
Skip,
Filling your gas tank is also dangerous if you don't do it properly and turn off your frig while filling. I seen plenty of station fires from motorhomes. Ask the Flying J at Lazy Days. As for equalizing, how many people do you know that are willing to hang around for 8 hours and watch some batteries vent during equilazion. I don't recommend that the average driver equalize, but if you are good mechanically it's ok.
Bill G. 2005 Magna #6425
Yahoo Message Number: 11505 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11505)
I don't know any and wouldn't want to hang around for eight hours to equalize either. There is no fast rule on how long it takes to equalize.... just opinions. Note that battery mfgrs don't specify a time and rightly so because the time varies by the state of the batteries which, they have no control. In practical terms a two to four hour equalizing intervals does a whole lot to perform an equalization process. But, that is subjective... again because defining the condition of the battery plates is not an exact science. Doing it two days, for a couple hours a day, while your around the MH is a reasonable alternative
My point being.... equalizing is not any more dangerous than many other maintenance items we do. The feature is there for a reason. Of course everyone is entitled to their interpretation of what is dangerous. By the same token, others are entitled to disagree. My preference is to provide some rational for my reasoning as to why it is dangerous verses a blank statement that it is not. Eight hours to perform equalization is not one of my beliefs unless I know I was dealing with some very bad batteries.... I would plan to replace them in that case.
Skip
-----
Filling your gas tank is also dangerous if you don't do it properly and turn off your frig while filling. I seen plenty of station fires from motorhomes. Ask the Flying J at Lazy Days. As for equalizing, how many people do you know that are willing to hang around for 8 hours and watch some batteries vent during equilazion. I don't recommend that the average driver equalize, but if you are good mechanically it's ok.
Bill G.
Yahoo Message Number: 11506 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11506)
To all regarding equalizing batteries;
As a long term boater I have always used this function to maintain the health of our deep discharge battery banks and do the same with our battery banks on the coach. I have added a link to the West Marine Advisor on battery charging, which I find to be very reliable information. Those of you that have access to the West Marine catalog may their West Advisor sections very useful with the text and drawings (and it can be accessed on the web site).
West Marine: West Advisor (http://www.westmarine.com/webapp/wcs/stores/servlet/WestAdvisorDisplayView?storeId=10001&langId=-1&catalogId=10001&advisor=smartbattery.htm)
Maintenance is the key to having more pleasure from our pleasure crafts (coaches).
Tom
2000 Magna 5764
1999 CRV toad
Yahoo Message Number: 11536 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11536)
John, and all others involved in this discussion.
I have a Magna (6477) on order and was concerned about this whole battery matter. I went to engineering and to customer service with the issue, saying that I want to make sure that any or all modifications were included in my coach. CC's response to me was the following:---
We completed testing a coach here and did not find the condition that Mr. Lewellyn has listed. Everyone must understand that coach 6400 is a special order and has additional batteries. The addition of the batteries across the bay from the main bank and the additional connectors may be contributing to the issue with this coach. Mr.
Lewellyn has stated that he is going to complete the testing that I am recommending so that we can find the root cause of the issue with his coach. The battery bank testing shows that the standard or all electric option coaches do not have the problem which 6400 seems to have.
--------------
Yahoo Message Number: 11537 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11537)
Hi to all, the other issue that has not been mentioned is the fact that the new TCS Silverleaf does not show amp hours in the batteries. Nor does it show the bulk, accept, float charge rate so it is just a guessing game as to how long to run the generator when dry camping. I like to know how many amp hours are available and when they fully charged. Dale Hollick 05 Affinity 6370
Yahoo Message Number: 11540 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11540)
Your right on Dale.... with a Link 1000 they put a "shunt" on the negative post of the house batteries between the battery and the cable to the power service for the MH. Across this shunt they have leads that go back to the Link controller. This shunt has engineered current flowing through it when anything in the coach sucks power. These leads measure that current flow. The Link does the math for current, across the shunt, going in when charging and coming out when drawing power. You program in the capacity of your batteries which the controller ads/subtracts the current flow. It does do other things and this is a layman's explanation of how it does that. It is a better way to show battery draw.
Measuring voltage is not the best way to determine the state of your batteries and is just an indicator. Bad/weak cells can provide a voltage reading that won't reflect the cells ability to provide the current it is designed for. That's why the gauges can say everything is OK but, a load test, which is really a current demand test, can show the batteries aren't performing to their spec. On new batteries you are probably OK but, when drawing them down a lot over time the current measurement method will be better.
I don't believe the Silverleaf measures current going in and current going out of the batteries unless there is a shunt on the coach batteries to measure across. Since it plugs into a control box up front I don't think it is set up for that...... but, I may be wrong.
Skip
======
Hi to all, the other issue that has not been mentionedis the fact that the new TCS Silverleaf does not show amp hours in the batteries. Nor does it show the bulk, accept, float charge rate so it is just a guessing game as to how long to run the generator when dry camping. I like to know how many amp hours are available and when they fully charged. Dale Hollick
Yahoo Message Number: 11544 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11544)
Skip, the biggest issue to me is not knowing the state of charge. If these AGMs do not get a full charge when running the gen, it will likely shorten their life. Do you (or anyone else) have any suggestions regarding this? Thanks, Dale Hollick 05 Affinity #6370
Yahoo Message Number: 11545 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11545)
Dale,
If I can jump in again with a link to West Marine's advisor section on Smart Battery Charging I think that you and others may find some very useful information in this "Marine" battery charging advice. There are several very useful Advisor Sections in West Marine's web site and catalog that cross over to our circumstances. Check this link ....
West Marine: West Advisor (http://www.westmarine.com/webapp/wcs/stores/servlet/WestAdvisorDisplayView?storeId=10001&langId=-1&catalogId=10001&advisor=smartbattery.htm)
Tom
2000 Magna 5764
1999 CRV
Yahoo Message Number: 11546 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11546)
Thanks, Tom, I will give it a try. Dale
Yahoo Message Number: 11547 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11547)
Dale, if I understand your question correctly a 100% full charge can be a bit difficult to 100% accurately define. Most good chargers will change to float when the battery internal resistance reaches the max charge level. A good charging system will show this by a meter or LED of some kind. Most people accept this as a full charge indication.
Using a device like a Link 1000, when you set it up, has you charge it up to a full charge where it goes to "float". The last 15% of charging takes almost as long as the bulk charge time when going form drawn down toward full charge. In other words, the charge curve is not linear.
Once you do this, you program in the rated capacity of your battery and such a device will calculate current in and out of the battery as well as time remaining until you get down to the % value you are willing to take it down too.
Skip
=======
Skip, the biggest issue to me is not knowing the state ofharge. If these AGMs do not get a full charge when running the gen, it will likely shorten their life. Do yu (or anyone else) have any suggestions regarding this? Thanks, Dale Hollick
Yahoo Message Number: 11551 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11551)
Sorry to have this be so confusing. Long story short, the 05 Magnas and Affinities have the Silverleaf TCS as the only means of dealing with the state of the batteries. There is no shunt, no Link 1000, no other battery monitoring device. I am just wanting to monitor, charge, and keep my batteries in good condition. I just want to know how all the other new coach are dealing with this and have a resolve. Thanks again, Dale 05 Affinity 6370
Yahoo Message Number: 11552 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11552)
I am going to check voltage readings cc has ask for, but their tech has checked already with me. He found the same readings I did.
Yahoo Message Number: 11574 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11574)
Dale
Why don't you just add a Link 1000/2000? I did & it's not that difficult to do, just takes time to run the wire from batteries to where you want the display.
Terry
99 Magna 5703
Yahoo Message Number: 11583 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11583)
As President of SilverLeaf, I'd like to throw in my two-cents worth on the topic of amp-hours.
Dale - we ALL would like a real amp-hour meter. Unfortunately, for us RVers they just don't exist. Simply enough, the whole concept of "amp-hour" is a pleasant fiction in an RV battery. It is a *battery rating* method that has little correlation to what you will see in the real world.
The fundamental problem is that a battery that lasts 100 hours at 1 amp won't last 10 hours at 10 amps, and definitely not 1 hour at 100 amps (more likely 15 minutes or less!). Products like the Link series use a shunt to measure the amperage, and they *attempt* to correct for the difference between heavy and light loads using a formula called "Peukart's Law". Unfortunately, Peukart's Law only applies for small ranges of amperages, not the huge swings we see in an RV when you turn on the microwave oven.
Xantrex sells a lot of Link and similar products in the marine market, mostly to sailboaters who use their batteries very lightly. In that context they work reasonably well. But today not a single RV builder still uses the Link series, simply because they aren't accurate across the range of loads common in a motorhome.
So what we all *want* simply doesn't exist. Pay no heed to the marketing claims.
So what are the alternatives? My dream would be to have a way of actually sensing the electrolyte levels in the battery itself.
Unfortunately, that sensor simply doesn't exist.
The next best thing is to place a reference load upon the batteries and measure the voltage. This is how it's done in industrial applications, such as hospital backup power. Unfortunately, we don't have a reference load. We have been experimenting with trying to use the current load as a correcting factor, but there is much "black art" to this. There isn't a simple formula for voltage versus current that applies across the board.
That leaves us with raw voltage. It seems John's problem isn't so much the technique, but the source of the voltage data. We'll keep working with CC and John until that issue is settled. Meanwhile, raw voltage is the most reliable indicator available at the moment.
(It is also the method used by every other genstart product on the market. These products vary only in the details, not in the general method.)
--
By the way, our system does show the charging rate and the current battery status (bulk/absorb/float). The bulk/absorb/float status is displayed only on the VMS 200 in the dash, not on the HMS 060 in the salon. We could easily have put it in the HMS 060 - it was simply a screen layout decision.
- Martin Perlot
Yahoo Message Number: 11584 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11584)
So what your saying is that if I want to know the condition of my batteries I need to look at the volts and use a hydrometer
As President of SilverLeaf, I'd like to throw in my two-cents worth on the topic of amp-hours.
Dale - we ALL would like a real amp-hour meter. Unfortunately, for us RVers they just don't exist. Simply enough, the whole concept of "amp-hour" is a pleasant fiction in an RV battery. ..................................
So what we all *want* simply doesn't exist. Pay no heed to the marketing claims.
So what are the alternatives? My dream would be to have a way of actually sensing the electrolyte levels in the battery itself.
Unfortunately, that sensor simply doesn't exist.
Yahoo Message Number: 11586 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11586)
Since everyone is talking about me and my electrical issues, I'll give my two cents on the previous reply.
The SW and PS series inverters from Xantrex do have the ability to set the genstart based on 24 hour voltage, 2 hour voltage, 15 minute voltage, and 30 second voltage.
It also has the ability to start based on load, with a programmable amount of amps for a programmable amount of time, such as more than 19 amps for more than 5 minutes. and it will shut off based on the load dropping for a set amount of time as well. Number of minutes delay before shutting back off can also be programmed. I tried to get Country Coach to install the SW inverters for me instead of their standard, but they made the cost so high I could not do it.
John
Yahoo Message Number: 11595 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11595)
I wish someone would invent the in-the-battery hydrometer that we could sense remotely. No one has. My next wish would be for there to be some moderate load that we could put on the battery whenever we wanted to (and turn off all the rest!) Of course, there isn't. So that leaves raw voltage as the best indicator at our disposal. (I'm talking only about the current battery level, not their overall health.)
- Martin
Yahoo Message Number: 11598 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11598)
Martin, I (and the board members) appreciate you taking the time to write an email to us regarding Silverleaf. I do hope that CC and Silverleaf keep working together in order to help the owners with the issue at hand. We do need to know accurate voltage from the battery bank and we do need to know amp hours available and state of charge. You mentioned that you would continue working with John until you have a resolve. I would hope it would be passed on to the other 05 coach owner's as well. Thank you again for your input, help and knowledge. Dale Hollick 05 Affinity #6370
As President of SilverLeaf, I'd like to throw in my two-cents worth on the topic of amp-hours.
Dale - we ALL would like a real amp-hour meter. Unfortunately, for us RVers they just don't exist. Simply enough, the whole concept of "amp-hour" is a pleasant fiction in an RV battery. It is a *battery rating* method that has little correlation to what you will see in the real world.
The fundamental problem is that a battery that lasts 100 hours at 1 amp won't last 10 hours at 10 amps, and definitely not 1 hour at 100 amps (more likely 15 minutes or less!). Products like the Link series use a shunt to measure the amperage, and they *attempt* to correct for the difference between heavy and light loads using a formula called "Peukart's Law". Unfortunately, Peukart's Law only applies for small ranges of amperages, not the huge swings we see in an RV when you turn on the microwave oven.
Xantrex sells a lot of Link and similar products in the marine market, mostly to sailboaters who use their batteries very lightly. In that context they work reasonably well. But today not a single RV builder still uses the Link series, simply because they aren't accurate across the range of loads common in a motorhome.
So what we all *want* simply doesn't exist. Pay no heed to the marketing claims.
So what are the alternatives? My dream would be to have a way of actually sensing the electrolyte levels in the battery itself.
Unfortunately, that sensor simply doesn't exist.
The next best thing is to place a reference load upon the batteries and measure the voltage. This is how it's done in industrial applications, such as hospital backup power. Unfortunately, we don't have a reference load. We have been experimenting with trying to use the current load as a correcting factor, but there is much "black art" to this. There isn't a simple formula for voltage versus current that applies across the board.
That leaves us with raw voltage. It seems John's problem isn't so much the technique, but the source of the voltage data. We'll keep working with CC and John until that issue is settled. Meanwhile, raw voltage is the most reliable indicator available at the moment.
(It is also the method used by every other genstart product on the market. These products vary only in the details, not in the general method.)
--
By the way, our system does show the charging rate and the current battery status (bulk/absorb/float). The bulk/absorb/float status is displayed only on the VMS 200 in the dash, not on the HMS 060 in the salon. We could easily have put it in the HMS 060 - it was simply a screen layout decision.
- Martin Perlot
Yahoo Message Number: 11601 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11601)
Martin... I disagree.. with the Link it has a shunt on the coach batteries (negative terminal) which captures all load or current draw IF you install it correctly. The shunt has a preset known resistance where there is a very minimal current drop across it ... like milliamps. Whenever there is a call for current on the coach batteries an extremely small percentage of higher current crosses the shunt proportional to the load placed on it. This current is measurable and that is what a Link does with respect to tracking current going in (charging) and current used (load in use). On initializing the system you are required to specify the rating and type of batteries and the math is plotted against that as well as charging voltage control.
It is about as practical and valid way to measure current as anything in the market today.
Hydrometer method is valid for lead acid batteries only and not a very convenient way to perform day to day measurements. It's use is very good as a test to see the condition of a battery and whether it cells are to the point where they can all chemically accept a charge equally. The batteries must be fully charged to get a practical useful reading for diagnosis. A load test on any battery is the ultimate way to see how much it can deliver.
Skip
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So what your saying is that if I want to know the condition of my batteries I need to look at the volts and use a hydrometer. I wish someone would invent the in-the-battery hydrometer that we could sense remotely. No one has. My next wish would be for there to be some moderate load that we could put on the battery whenever we wanted to (and turn off all the rest!) Of course, there isn't. So that leaves raw voltage as the best indicator at our disposal. (I'm talking only about the current battery level, not their overall health.) Martin
Yahoo Message Number: 11608 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11608)
Could this type of metering be "more correct" than what is being offered now. It may be the $199 solution to all of our questions.
The following can be found at "www.measureanything.com" where pictures and detailed data sheets are available.
MAGNA6477
Datasheet: Cruzpro VAH 30 Battery Monitor Digital Volts-Amps-AmpHours ,
with alarms for low / high voltage, low battery The VAH-30 displays battery voltage and charging or discharge current and tells you how much battery capacity has been consumed and how much is remaining. It keeps track of all current entering and leaving the battery and applies the appropriate Peukert's and efficiency factors. You can set Low and High voltage alarms and Low Amp-Hours Remaining alarms. When activated, the VAH30 built-in 85 dB alarm will sound and the display will flash. Five levels of backlighting can be selected and all set-up, calibration constants and alarm values are saved to non-volatile memory. The VAH-30 comes complete with a calibrated 150 Amp shunt to measure current.
All constants and calibrations are pre-set during manufacture but you may alter these settings to suit your particular needs. Calibrations can be altered using the front-panel switches for: Battery voltage, battery current, charge efficiency, Peukert's exponent, battery bank capacity (in amp-hours), low and high voltage alarms and low amp hours remaining alarm value. An auto-zero function is easily initiated from the front panel to zero the ammeter.
With a press of the button you can display battery voltage (9.5 to 33.0 VDC), current being delivered to or draining from the battery (- 150 to +150 Amps), the number of amp-hours remaining in the battery bank (0 to 3000 Amp-Hours) or the percentage charge remaining in the battery bank (0 to 100%).
High volts, Low volts, and Low Amp-Hours Remaining alarms can be independently set using the front panel switches and all alarms can be turned ON/OFF simultaneously with the press of a single key.
The VAH30 draws only 0.017 amps and is designed to be left on continuously. 5 levels of backlight (including OFF) can be selected from the front panel and is saved to non-volatile memory.
The VAH30 outputs Voltage, Amps and Amp-Hours Remaining on the standard NMEA 0183 serial data line at 4800 BAUD. This ASCII information can be used to log battery performance or repeat the display information elsewhere.
NZ1008-VAH30 1-lbs $199.00
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Yahoo Message Number: 11612 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11612)
This is exactly the type of product that I was refering to that works fine in a sailboat but breaks down in RV use. The problem is that in our coaches the loads vary over huge magnitudes. "Peukert's Law" is really nothing more than a type of approximation which is valid only for relatively small variations in load. (One of the things you can deduce from Peukert's Law is that if the load is sufficiently small, your batteries will last forever!) You can pretty much ignore any product that even mentions Peukert. They are fine for many applications, but our coaches aren't one of them.
- Martin
Yahoo Message Number: 11613 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11613)
The Trace SW series does have these additional triggers. The PS series has no genstart at all. I didn't mention the SW series because most people on this site are familiar with the Trace RV series used in most CC products. The RV series is as I described.
The SW series is much more expensive, and they are HUGE. I imagine that putting a pair in a CC would require some major changes in the compartment layout.
You may find it interesting that two of our other accounts use the Trace SW series, but use our module for the genstart. The main reason is complexity. Of course we *could* offer a half-dozen different triggers, but most people just want one. Adding extra triggers wouldn't necessarily add extra value.
- Martin
Yahoo Message Number: 11615 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11615)
You are correct in saying that a shunt is a "practical and valid way to measure current". But that isn't why shunt-based amp-hour meters don't really work. The problem is rather counterintuitive.
You would think that calculating the battery level would be just a matter of counting how many electrons went out, and how many went back in. There are only so many electrons in there, right? Unfortunately, that simple idea just isn't true. Counting electrons works only when the loads vary only in a fairly small range. But in an RV the loads vary tremendously - watch your amperages when you turn on that Advantium oven!
(You are also correct in your observations regarding a hydrometer, although I'll point out that the hydrometer will tell you relative level when the battery is partially charged. But it's impractical, and your final conclusion is correct: a load test is the ideal way.)
- Martin
Yahoo Message Number: 11628 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11628)
Martin, I've been following your statements about Peukert's equation being invalid for large current ranges in RVs. However, I'm unable to find any reference to support what you say. Could you please provide such?
This is a very interesting topic to the DieselRVs group also as many of us rely on Link monitors.
Could you post your reply there also? Thanks,
Tom Fisher
Dallas, TX
Yahoo Message Number: 11629 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11629)
Also, I see no difference in a 35-45ft sailboat vs a 35-45ft motorhome. Both have microwaves, TVs, etc. Again please provide some references for your statements. I'll also forward your statements to Xantrex, AmplePower, etc. to allow them to comment.
Tom Fisher
Dallas, TX
Yahoo Message Number: 11632 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11632)
I agree so many might be confusing for some. I do like the starting over a load value on the sw or ps with optional gen start.
John
Yahoo Message Number: 11688 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11688)
If you are interested in how science progresses - or sometimes doesn't - then this is an interesting story. It's a fascinating example of how generations of scientists and engineers will repeat whatever they learned in some undergraduate lab class and never seek to understand the facts behind the formulas. In this case the result is a formula that is taken for granted by (almost) everyone in the field, yet has absolutely no validity.
lots of jargon and absolutely no intrigue. Like the story of Spider-Man without Mary Jane, Doctor Octopus, or the radioactive spider.>
The formula dates to the 19th century! I don't know anything much about Mr. Peukert, but he was trying to find the same thing we are trying to find - the answer to "how long will this battery last". He didn't get very far. He couldn't come up with (nor apparently has anyone else) a real mathematical model for understanding battery discharge. Instead he noted that the relationship between current levels and amp-hours attained is not linear. So he fit the data to an exponential curve - even though an exponential relationship is physically absurd. He could have chosen a parabolic fit just as easily. Like any curve-fit, the result is "pretty good" in the immediate neighborhood of the known data points. But it blows up outside of that narrow band.
I discovered this some years ago when SilverLeaf was considering a shunt-based state-of-charge product. But while all the engineers I talked to pointed to Peukert's Law, as a *mathematician* it bothered me. I could easily see that the formula let to absurdities, and so I researched it further. As a mathematician it was obvious to me how Peukert derived his law and how limited it really is. Yet the formula has been passed down from textbook to textbook for generations!
Over the years I've learned of a lot of these "urban legends of science". I remember learning in elementary school that your taste buds were arranged in a certain way on your tongue - sweet at the tip, bitter at the back, sour and salty on the sides. Absolute claptrap! Taken from a 19th century text written by a half-loony amateur. And repeated in textbook after textbook and never challenged. (All tastebuds are equally equipped to detect any flavor.) And every flying enthusiast knows that the lift on a wing is provided by Bernoulli's Principle - a fact repeated since the Wright Brothers. It isn't.
There is a fine doctoral thesis for the engineer who wants to replace Peukert's Law. I have no doubt that it can be done, but it is considerably more complex than people realize. Unfortunately, often the presence of these "urban legends" discourage further research in the area. Budding young scientists and engineers rarely challenge accepted laws in their research. (Can't blame them. It really torques their professors.)
I think that's about as much as I can say without trotting out the actual formulas. If you are still awake at this point in this little dissertation, I salute you!
- Martin Perlot
(M.S. - Applied Mathematics, Oregon State University)
Yahoo Message Number: 11689 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11689)
Tom,
I'm not terribly interested in a debate with other vendors on this topic. What exactly do you expect them to say? Of course they'll say their products work, and Peukert's Law is the standard in the industry. I have said Peukert's Law is nothing more than a simple curve fit that works only within a narrow range of current values. I say it breaks down under the wide ranges of currents we see in a coach.
Now what?
The proof of the pudding is in the eating. There are hundreds of Country Coach products with the Link installed. The owners of these coaches are the ones with our answers.
Ask them.
Yahoo Message Number: 11690 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11690)
This is the statement that I'm particulary interested in. Please provide some references for your statement that "it blows up outside of that narrow band". I can't find a single reference on the web that states this. I also know many folks using the Link meters and *none* of them complain that they feel they are innacurate.
Tom Fisher BSEE, MD
Dallas, TX
Yahoo Message Number: 11691 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11691)
I have asked *many* and I haven't heard *any* that are unhappy.
Can you provide references of any folks that can provide actual observations that the meters are missleading and/or more problematic than voltage/SG measurements?
So far you seem unable to back up anything that you say so I'll just assume that you can't. Still waiting...
Tom Fisher BSEE MD
Dallas, TX
Yahoo Message Number: 11692 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11692)
Martin, Had my Math and Science instructors provided class information in such an interesting fashion, I probably would have been a scientist instead of going into the career field I followed!
Thanks for clearing the mud a little. :)
Carol'04 Inspire Genoa 51046
Yahoo Message Number: 11693 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11693)
Hopefully, your mentors could cite references for their statements.
The good ones always do....at least mine did.
Tom Fisher BSEE MD
Dallas, TX
Yahoo Message Number: 11712 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11712)
Martin, it just occurred to me that NASA has obviously solved the problem of battery monitoring as the Mars Rovers, etc. certainly depend upon such. I wonder what NASA uses? Anyone? Tom Fisher
Dallas, TX
Yahoo Message Number: 11719 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11719)
Tom
I have asked *many* and I haven't heard *any* that are unhappy.
I have used a Link 1000 on this coach for almost 6 years & the previous one for 3. While I wouldn't be without one I don't find them to be extremely accurate.
The out amp hrs never agree with the in charging amps especially after days/weeks of dry camping I have had the meter show more negative amps that my battery capacity even after running on float for hrs. I am a heavy user, 40 amps per hr at night & have spent up to 6 months off the elec grid in the Quartzite area. It seems to be much more accurate when using light loads than heavy & I use it in conjunction with my volt meter & manually zero out the amp display every couple of days.
Terry
99 Magna 5703
Yahoo Message Number: 11722 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11722)
I'm confused about this. If you are saying that the meter indicates that the amphrs
drawn from the batteries is always greater than the amphrs needed to charge the battery;
this is always correct.......read your manual about CEF(charge efficiency factor).
Also, make sure you have entered the correct Peukert's number for your batteries.
You will never get as many amphrs out as you put in....typically only 85-95%.
RTFM
Tom Fisher
Dallas, TX
Yahoo Message Number: 11724 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11724)
Tom... sounds like your perspective on accuracy is right on! Mine will go to negative also but, it is a very small, number. Beats relying on the voltage only reading I had with the Inteletec system that came with the MH. We are heavy users with our U-line and morning breakfast habits. I added two 6v batteries, set the peukert factor, total bank capacity, and set the bottom threshold to 40%. Watching amps in - amps out is a useful tool. ... IMHO.
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I have used a Link 1000 on this coach for almost 6 years & the previous one for 3. While I wouldn't be without one I don't find them to be extremely accurate. The out amp hrs never agree with the in charging amps especially after days/weeks of dry camping I have had the meter show more negative amps that my battery capacity even after running on float for hrs. I am a heavy user, 40 amps per hr at night & have spent up to 6 months off the elec grid in the Quartzite area. It seems to be much more accurate when using light loads than heavy & I use it in conjunction with my volt meter & manually zero out the amp display every couple of days. Terry
Yahoo Message Number: 11725 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11725)
Also, IF Peukert's equation is correct, it follows that the total amphr capacity of two
batteries in parallel is *greater* than twice the amphr capacity of a single battery.
For any given total load, the current is then half of what it was for a single battery. Thus
the capacity of two 210amphr batteries is equal to 210 x 2^1.25 = 210 x 2.38 = 499.8amphrs
*not* 420amp hrs for Peukert's exp = 1.25.
Tom Fisher
Dallas, TX
Yahoo Message Number: 11726 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11726)
Oops.....should read amphrs drawn is always LESS than needed to charge.
Tom Fisher
Yahoo Message Number: 11738 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11738)
Please don't go back to the Links in any new CCs. Since I never equalize my batteries and still get 4 years out of each set, who needs the Links. I did not think it was that reliable. I also believe that we try to put to much data in our systems. I like the new Slverleaf Total Coach System, its simple and easy to work with. and i don't miss the Links
Bill G. 2005 Magna #6425
Yahoo Message Number: 11739 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11739)
Bill, how do you suggest that folks monitor their batteries when drycamping?
Tom Fisher
Dallas, TX
Yahoo Message Number: 11783 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11783)
Tom,
The new Total Coach System with auto-generator does a fine job of monitoring the batteries without the need to do anything. You set the voltage to whatever you want on the Silver Leaf and when the batteries get to that point the generator comes on and charges the batteries back up to the level you set. This works for me and it is good for the generator as well. Plus it keeps the batteries from discharing to much and creating the need to equalize.
When I had a Links in my old Mag I had to do a lot of this manually and the Links had to be reset all the time to keep it from acculating error. My last batteries lasted 4 years without equalizing. We kepted our batteries up during storage with solar panels.
Bill G. 2005 Magna #6425.
Yahoo Message Number: 11784 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11784)
Sounds like a very nice system BUT unless it truly monitors current flow in/out of the batteries and battery temperature, most experts would agree that it is *not* the optimal system. Xantrex makes an excellent inverter/ charger system for ~$1500-$2000 including autogenstart that is highly regarded.
http://www.xantrex.com/Products/supercat.asp?did=289 (http://www.xantrex.com/Products/supercat.asp?did=289) I have no financial interest here but I do own both the Link 10 and Link 2000 monitors from Xantrex. I use both for a battery monitoring and autogenstart system that I designed and installed in my DSDP. I find them both to be very accurate and usefull. I also have found Xantrex product support to be outstanding.
This is only a hobby project only as I have *no* products for sale.
Tom Fisher
Dallas, TX
Yahoo Message Number: 11788 (http://groups.yahoo.com/neo/groups/Country-Coach-Owners/conversations/messages/11788)
tom,
We have 2-3000 Xantrex inverters tied into our total coach system..
Bill G 2005 Magna #6425.