TIP # 154 Dissertation on Batt Voltages to Expect in Living w/Multi Charging Sys

Submitted: Thursday, Mar 22, 2007 at 19:34
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Newbies in the planning stage, here is some general reading for you off the Owners Forum to give you a feel for how the Solar and Battery Charger systems work...

Over the 12 years of Bushtracker we have slowly moved towards developing systems that monitor and regulate the systems for you. That is why our Solar Regulator has so many LED readouts, and the rolling digital read out of input, load, and battery volts as well as the readouts of "State of Charge", alarms and all the rest. And that is why our Battery Chargers now have alarms as well, temperature monitors on case and batteries, and their own digital readout panel, even beep codes to talk to you all in order to take care of the systems for you. You cannot buy gear this good, we had to develop it. There are not any Regulators or Chargers on the market that are this "User Friendly"... Just like the Bushtracker Van, these essential services are the Best and most important in living independently.

Here is some reading for you to understand the systems you will be living with: TIP # 154..............

In the old days (yea, I am a dinosaur) you did not charge by voltages, you charged by “specific gravity” measure of the battery acid/water through the filler caps in each cell… This had to be done if the battery was in Service at the time.. You could charge a battery while it was in use, and not achieve the top end of the finishing voltages you would expect while under load; so the only practical way to test it was by the level of acid (electrolyte) moving in and out of the plates in each charging cycle. You did this most commonly with a turkey baster style of Specific Gravity tester, and it would tell you in percentage terms the state of the charge by measuring the electrolyte floatation of an indicator inside, which showed you the state of charge according to how it floated in the electrolyte (acid) water mix… Any way, you might get a fully charged battery, that was under load, where you would never see the top end maintenance charge that equalized the cells, hence the measure of “specific gravity”… Floatation of the acid water mix (electrolyte)… Never mind, not really applicable to our battery style.

Sealed batteries put an end to this….. Now we have to go on voltages, and that is why I give a range that is acceptable… The electronics that can determine the charge state are a bit of witchcraft and black magic… Ha! But it is all we can go on with sealed batteries. Now the variance in me giving you the voltages as a range, is due to outside influences like temperature, and what you have running on them at the time (load), and other things like “age” of the batteries.. So I am giving you a range of voltages to work with... This will also vary with the seasons and how they charge with different relative ambient temperatures, so you are likely to see what they call a “Seasonal Variation”.

In all fairness, I have never met anyone that has experimented around with German A-200 Gel type batteries more than I have. My first ones were (2)-200 AH sealed batteries in a yacht in 1990, and I ran them against normal (2) 8-D size 200 AH 150 lb wet lead acid marine batteries in two separate banks with a “Make before Break” Cole Hersey Battery Bank selector switch that made the next connection before breaking the last connection.. I could switch them under charge without blowing the diodes in the Alternators of engine and generator, and test them on Solar and Wind Generator. This experimenting went all the way up to a Seven year test of them with battery voltages in storage per TIP # 95…(Owners Forum) in the 1990’s I have proven the recommended voltage levels first hand, and my results confirmed the Manufacturer recommendations, so you can take it to heart. I do not go around collecting opinions, I prove the science of things I test… These voltage levels have been Proven, my test of ten of them long term per TIP # 95 alone cost about $3500 and YEARS of studying how they reacted. These tests continue up to today. Even now I am building a 100 amp unit to charge 10 batteries at a time at 10 amps. I do all kinds of tests.. The lone Ranger lives like this…. Trying to find ways to do it better… So, here it goes:

If you were to watch the whole cycle of charging, you would see that on 240v, “Boost” in the first few hours after you plug in (depending on how low your batteries were as to how long it took to get them back up), your charger would equalize the plates and do the high end maintenance charge up to about 14.-14.4 volts at a peak. After a few hours, you could then see it drop down to about 13.8-14 volts on what is called “Float” where it just maintains them at a fully charged state. It will not go back to a Boost cycle until you plug in again, or on a timed interval depending on the charger, about once every ten days if you stay plugged in... These are the desired ranges of a sealed or gel cell battery. People could see 14 volts on Float, in the right season or when solar is running.

On solar alone: If you were to look at them at the peak of sunlight during the day, you will probably see them up around the 14 volts as well. If nothing is running, if the batteries are young in age, in ideal conditions you will see the solar up at the 14.3- 14.4 as well… On Solar Science if you are interested: There is a slightly different charging algorithm on solar, as it is a smooth and light charge. To squeeze it in more in minimal light, when the charge rate is at lower amperage, it has a process where as if it stores it up and injects it like a capacitor, in little squirts of higher amps at a short burst… That is the way to visualize it, how it actually works is PWM: Pulse Width Modulation, that squeezes in a little more power off an otherwise light and smooth charge, by switching on and off the panels in a timed burst that keeps the panels cooler and at a slightly higher potential.. So it again sort of puts in the amperage a slightly higher bursts which means higher efficiency in low light as a function of our Regulator.. Anyway, forget all that black magic mumbo jumbo, I am getting off the track here… You will see your batteries up in the 14 volt range on solar as well, possibly higher. But again, it depends on the temperature, what you have on, and age of the batteries, as their efficiency of acceptance of charge, and their resistance, changes as they age…

Test line- For example: On solar alone and fully charged, but at 4PM seeing solar still going in, with anything on, you are not getting much appreciable charge but you could see solar going in and you might only see the “Resting State” voltage of 12.8-13 volts.. OH NO! Well don’t worry… The problem is probably that you are pulling out as much as you are putting in, and you might only see the battery "Resting State" which again would be right about what a fully charged battery is at 12.8-13 volts.. So you could be alarmed in that you see solar going in, but only a resting state of charge on the batteries, this is still normal… 95% of the worries that people have is in spot checking something that travels in a range of movement in a cycle so to speak.. There is no end to toys you can buy to tell you more, but all it will do is confuse you more, because the toys cannot be calibrated to reflect age of the batteries and drop of efficiency and other outside factors. Because of that we discourage use of the other toys. All you need is on the solar regulator.. And the battery monitor that comes with the new charger…

QUESTION: Now for the science of things, why the upper range of the charging cycle at all??? ANSWER: You need to hold the batteries up at the top level for a given time at a given voltage, around 14.8 -14.9 for normal wet lead acid batteries, and 14-14.4 for sealed batteries, to give time for the “slower cells” to catch up to the fully charged state… Slower Cells? From new they are not all perfectly even, not all perfectly the same, and they age differently. So one lower potential cell does not drain down the others, they need to be “Equalized” to the same potential over a time interval to bring the slower or lower cells up to the same point.. In wet lead acid batteries it will boil along as it sets up there to “clean the plates”, and also equalize the cells to their highest common potential voltage. It is a little different in AGM Gel batteries, but the net effect is the same, to “Equalize the cells”… Otherwise, as I said, one lower cell will pull the others down, and you end up with a battery that is only charged to the 90%... Then a lower cell can pull it down to 80% and so on…

Now if you were to see your charger setting on 14.3-14.4 volts for a protracted period of time, it is ‘Stuck’ on Boost. Noosa Fox said his was sitting there for days…. That is NOT an accepted norm. There is something wrong there. Without seeing it here are a few causes:
1) It could be that one or more batteries are a bit tired, and the charger is struggling with that…
2) It could be that there is enough equipment running that the charger cannot switch out of boost, it stays ‘stuck’ on Boost, we have seen that time to time…. This is very common with some other types of chargers… Very rare with ours, non- existent with our newer ones..
3) It could be that there is solar input contributing to the readout, only looking at it in daylight.
4) It could be that the charger control module is defective, however we only find that on a very rare occasions. Most of the time it is due to an external influence that this happens like #1 or #2 or #3 above. It is better if the charger switches to “Float” at 13.8 to 14 volts, as it is better for the batteries not to be kept over that long term… Now not to be alarmed, and do not worry about it, if you are only on battery charger for short periods. Noosa Fox, you do not need to fret, situation is not normal, but also not serious…
If you LIVED on the battery charger, that higher rate could shorten the life of the batteries with what is called “Heat Degradation”, where they are a bit too warm for too long, getting rid of the extra charging energy in heat dissipation. For shorter periods of a few days to a couple of weeks, I would not worry about it too much. But for longer periods, living on power full time…??? Then yes.

QUESTION: So, why the higher voltage level on solar and why is that acceptable? Because the solar will hit optimum levels, if at all, for only a few hours a day. This will not even be achieved if there is a load on, say when the fridge is running, and you would be lucky to see 14 volts. In other words the solar is not on a peak voltages for long enough to heat the mass of the batteries long term enough to cause heat degradation… This is only a factor of concern on 240 volt, 24/7, longer term… OK?

In summary, here are some general rules:
A) You cannot see the entire charging cycle as it takes many hours. A spot check is useless if you do not know where you are in the charging cycle. Most concerns are unwarranted because of this… Almost ALL calls of concern to Bushtracker are due to this….
B) On the 240 mains charger, you want to see it hit a higher peak of over 14, as high as 14.4 volts in the first 2-6 hours or so, depending on how far down your batteries are, and what size of charger you have, and how many batteries you are running. Figure on about 3-4 hours average with newer 50 amp and four batteries, but this can vary with what load you have on… Or how far down they were…
C) It will hold them there for an hour or two to equalize the cells and then drop to “Float” and only put in what you take out and enough more to hold the batteries at 13.8 to 14 volts…. Good long term…
D) It will cycle back to “Boost” every 10 days or when ever you plug in again somewhere else… By Design.
E) During the daylight on 240 volt power: You cannot tell what solar is doing at the same time. You might be really at a float of 13.8, but show 14 volts on the Regulator due to the solar input. This is nothing to worry about, and within acceptable ranges. As I have said the solar input up at the higher levels is temporary…

F) At night, with no solar, and no power (no charger) you should see voltages around 12.8 to 13 volts which is the normal range of fully charged batteries at “Resting State” with no load on. It will drop accordingly with the load. This is with no 240 volt power and no charger on…

If, there is something in your system, some load that keeps the 240 volt charger on “Boost” at higher levels even at night with no solar input (check that as you may be seeing the solar pushing it there in daylight), if you see your charger sticking on boost due to some outside load factor: It is not a concern unless you are living in the van and staying somewhere long term on 240v power. IF this is the case, I would like to see them lower, so you can do a number of things to correct this:
1. You can switch off the charger at night at the Circuit Breaker in good weather solar input days when you are full.
2. You can have the charger re-calibrated to lower levels..

If it is only a sporadic problem, on 240 volt far less than half the time, like most Bushtracker Owners, then don’t worry about it…. This is a non-event, I am just giving you a full education of what to expect in normal ranges…

SUMMARY: So figure Resting State, 12.8 to 13 volts in a fully charged battery, “Float” at 13.8-14 volts long term on the 240 volt charger, and as high as 14.4 volts on “Boost” which you will rarely ever see… These are all normal voltages.. Your batteries will last the longest if you keep them run down no lower than 12 volts. But they can happily go down to 11.5 volts. And it will not hurt them if very rarely you get down to 11 volts… Any lower and you are hurting them and shortening their lives…

I hope my efforts are appreciated, and eliminate some of your concerns, by putting into terms that you can live with by understanding better what is going on… Putting it here on the Public Forum as well was a bit of an afterthought, but I am not giving away our R&D as our Regulators and Chargers have more user friendly readouts and functions than anything else on the market, but we own them, they are Proprietary equipment. You cannot buy gear this good, except from us...

Kind Regards, and Happy Trails from the lone Ranger…..

Email from the U.S. tells me that the Lone Ranger was actually a Texas Ranger as well… And also some obscure little bits like that Tonto’s horse was named “Scout”… Ha! Ha! Yea I know, Silver was Roy Rogers horse, but I have a Silver anyway.. Playboy, Silver, Dunnit, Quick, Amigo, and Whizz…
And the fat old lone Ranger won the Intermediate Non-Pro and Open Non-Pro on "Playboy" (Yulgilbar Oaks Playboy) in Gatton last month...

There is hope for me yet... I aim to be Open Non-Pro Champion of Australia... (yea, when pigs fly..)

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Reply By: Bushtracker - Friday, Mar 23, 2007 at 20:30

Friday, Mar 23, 2007 at 20:30
NEWBIES, Once you Order and are in the system, you can gain access from the Boggers that run this Forum, to the Owners Section... Here are a couple of samples that give you some Owners Issues relating to the Posting, the kind of questions and answers on the Owners Forum that relate just to Owners. You see, Tips on the Owners Forum are more geared to specifics and situations for Owners themselves, as well as private camping areas and Stations and places that the Owners want to keep to themselves.... I only transferred this one here as a matter of general interest, and to show you something to look forward to when you join....

'Hm & Er' On The Road replied to the question

Steve

We are currently house sitting in Crows Nest Qld, for a month while friends are overseas in India. (Yuck! rather be here in Oz!!)
The BT is sitting in their back yard.
All power in the BT, including the fridge has been turned off, and its NOT hooked up to 240v. Just relying on solar to keep the batteries charged.
In the above tip which boost light are you talking about?
The one up on the Solar Charge Regulator or the one down on the 50 amp charger?

Bob & KC
Bob & Kaycee


FollowUp 1 of 2 posted 22 Mar 2007 at 07:51 - (FollowupID: 3572)
Bushtracker posted this followup

Bob and KC,

On solar, you have no concerns.... It is only when left on the 240 volt charger long term that voltages are a concern as if the Boost gets stuck per the above, it holds them at the higher voltage above 14, as high as 14.4, 24 hours a day. Then the battery has to get rid of the excess energy in heat... There lies the problem..

On solar, obviously if you see the upper ranges it will only be for a few hours a day with nothing on. And it will shift off of boost and go over to float in itself. Off 240, you have no concerns...

Regards, Ranger
"The Last Stand In Open Country"



FollowUp 2 of 2 posted 23 Mar 2007 at 07:47 - (FollowupID: 3581)
Bushtracker posted this followup

I accidently deleted your question off the Member Messages, so here is your answer:

When not on 240v, just on solar, there is a yellow LED light that comes on the remote control panel of the new battery charger.... Yes it is the same light as the Boost but it obviously cannot be in Boost Mode as it is not on. It has nothing to do with the solar input, it is just a Default Mode showing the charger is hooked up to the batteries but not on. IT WILL BE ON BOOST WHEN you hook it up, it is just sitting there on the Default Mode READY TO GO TO BOOST as soon as you plug in the power...

It should be in your manual...
"The Last Stand In Open Country"






Reply 2 of 2 posted 22 Mar 2007 at 13:25 - (AnswerID: 11299)
Kenso replied to the question

Ranger,
Thanks again for the excellent tips and I believe i would be speaking for all in saying that of course your effects are appreciated! I'm blowed if I know how you get time to write at all!!. In relation to the above, when we first got the BT (manufactured Oct 05) I removed and cleaned all 4 batteries. I noticed that one had moisture and a Grey jell substance on the top. What is this? and what do think would be causing it?

Also on a older matter regarding the hot charger have fitted a 80mm x 80mm 240v cooling fan above the cooling fins in the charger and battery charger is much much cooler. Also our daily temp has finally started to drop below 42c which is also much more pleasant!

Thanks again in advance!

Kenso
19' BT 2005, 2005 Discovery 3 SE TDV6


FollowUp 1 of 1 posted 22 Mar 2007 at 13:36 - (FollowupID: 3577)
Bushtracker posted this followup

Kenso,
Thank you for the comments.... I do try, and luckily can type about a fast as I can speak or think for that matter. Took a professional typing class in the 60's, you know, one of those things you think you are never going to need??? So it is a bit of a natural.. But thank you for the comments. It lightens the load on the rest of the Office Staff when I have a big library of TIPS and answers on things to send out to questions. And, just like for Doctors and Nurses, a bit of "Continuing Education"....

Now on your batteries, about one in 25 or so of the last batch, were slightly overfilled. At least this is what we think. The other theory is that they do gas a tiny little bit when fully charged at the top end, and the corrugation could shake a bit of the gel up by the gas venting to blow it out.. In either case, it is nothing to worry about, just a little bit of cleanup.. That is why the TIP # 78 "Maintenance on Maintenance Free Batteries..." getting you to have a look at them now and then for a clean, or loose or broken terminal wire or what ever...

You should be getting your copy of the DVD today, or tomorrow at the latest... Hope you enjoy it.

Ranger

"The Last Stand In Open Country"






AnswerID: 570899

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