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Author Topic: Why are the 2 volt cells in the center of my string not getting charged fully?  (Read 10347 times)
martin
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« Reply #45 on: October 22, 2013, 04:31:53 PM »

I admire your honesty!  - we've all made daft mistakes, it takes cojones to admit them! genuflect
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Iain
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« Reply #46 on: October 22, 2013, 04:47:50 PM »

Hi Magnus
I use one of these, so takes the draw from the whole 24 volt bank and provides 12volts. So should overcome that problem.

http://www.alfatronix.eu/1481-powerverter-24vdc-12vdc-voltage-converters.php

Normally quite a few on eBay various sizes
Iain
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« Reply #47 on: October 22, 2013, 05:05:28 PM »

Agreed, they're good pieces of kit, and pretty efficient!
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Tinbum
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« Reply #48 on: October 22, 2013, 06:36:13 PM »

I come across this all the time with people connecting 12v equipment in a 24v vehicle. For the sake of saving a few they knacker their battery. Even the very smallest load will result in one battery failing.
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« Reply #49 on: October 22, 2013, 09:06:13 PM »

Delighted to hear thing are getting back in balance for you Marcus .  Lucky it only a couple of months  it should not have done to much damage .

 when  you originally posted  you said -


"  the 3 batteries closest the positive terminal needed 300 cc water.  the 3 batteries nearest the negative terminal needed 200 cc water and the 6 in the middle were still on the max water line.  "


I am puzzled .     

   Can anyone explain why  there was a difference in the amount of water gassed off between the different ends of the entire bank

all those 6 cells were subjected to the same degree of overcharge.
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Eleanor
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« Reply #50 on: October 22, 2013, 10:18:05 PM »

Magnus, glad that you found the cause of the problem and your cells are recovering. It's interesting as it sort of corresponds with the debate bxman and I were having. Bxman, I think I understand what you meant now. In "my thread" there was a suggestion by a couple of Forum luminaries that it would be a good idea to put a small load eg light bulb across the cells which were charging at a higher voltage to bring the voltage down so that other cells could charge at a higher voltage. This was before it was realised that in my case the cells were different. Your idea seems to use other cells from the pack to take the place of the light bulbs and do the same thing.

Magnus, it seems that you were putting a small load across some of the cells and reducing their charging voltage so they could never be fully charged ..........  keep on doing daft things like this and you'll end up being a Moderator  Grin

[PS You have a long way to go on doing silly things before you catch up with me  Roll Eyes]
« Last Edit: October 22, 2013, 10:21:03 PM by Eleanor » Logged

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billi
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« Reply #51 on: October 23, 2013, 04:59:00 AM »

Glad to hear the news .....

Now you can float  ..... how i wish, i would have a constant stream .....

Batteries , that are built to last , must be very cheap , if constantly charged
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« Reply #52 on: October 30, 2013, 10:10:43 AM »

all batteries are holding between 2.01 and 2.25 in the bank now (2.23 being the ideal).  that is within specs, so i will leave it alone for awhile to allow the cells to adjust themselves with repeat discharge/charge cycles.

i am still trying to wrap my brain around amps and flow of electrons. 

the clamp on amp reader is very useful to understand where the amps are moving.  ultimately this is what led me to realize that .7 amps were going to the stereo and NOT to the center 6 during float charge and even the last few hours of absorption in PWM. 

luckily the 9 watt load was hooked up for less than 60 days, so i think there will be no permanent damage to a very nice bank.

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magnus
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« Reply #53 on: October 30, 2013, 10:32:56 AM »

Hi Magnus
I use one of these, so takes the draw from the whole 24 volt bank and provides 12volts. So should overcome that problem.

http://www.alfatronix.eu/1481-powerverter-24vdc-12vdc-voltage-converters.php

Normally quite a few on eBay various sizes
Iain

thanks for the tip, i am in contact with the company now!
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magnus
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« Reply #54 on: October 30, 2013, 10:39:09 AM »

Glad to hear the news .....

Now you can float  ..... how i wish, i would have a constant stream .....

Batteries , that are built to last , must be very cheap , if constantly charged

billi, i need a translation.  this seems like a Koan to me, what do you mean?

now the rain has started, i could run a second turbine if i could afford it.  so much water!!!!!
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Eleanor
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« Reply #55 on: October 31, 2013, 06:52:29 PM »

all batteries are holding between 2.01 and 2.25 in the bank now (2.23 being the ideal).  that is within specs, so i will leave it alone for awhile to allow the cells to adjust themselves with repeat discharge/charge cycles.

i am still trying to wrap my brain around amps and flow of electrons. 

the clamp on amp reader is very useful to understand where the amps are moving.  ultimately this is what led me to realize that .7 amps were going to the stereo and NOT to the center 6 during float charge and even the last few hours of absorption in PWM. 

luckily the 9 watt load was hooked up for less than 60 days, so i think there will be no permanent damage to a very nice bank.




Magnus, 2.01V is very low. Have you done any SG measurements on the cells to check their state of charge?

Is this the data sheet you are using :

www.tab.com.es/Documentos/Opzs/NAVODILA%20-%20Operating%20instructions%20for%20stationary%20batteries%202009.pdf
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« Reply #56 on: November 04, 2013, 11:42:49 AM »

all batteries are holding between 2.01 and 2.25 in the bank now (2.23 being the ideal).  that is within specs, so i will leave it alone for awhile to allow the cells to adjust themselves with repeat discharge/charge cycles.

i am still trying to wrap my brain around amps and flow of electrons. 

the clamp on amp reader is very useful to understand where the amps are moving.  ultimately this is what led me to realize that .7 amps were going to the stereo and NOT to the center 6 during float charge and even the last few hours of absorption in PWM. 

luckily the 9 watt load was hooked up for less than 60 days, so i think there will be no permanent damage to a very nice bank.




Magnus, 2.01V is very low. Have you done any SG measurements on the cells to check their state of charge?

Is this the data sheet you are using :

www.tab.com.es/Documentos/Opzs/NAVODILA%20-%20Operating%20instructions%20for%20stationary%20batteries%202009.pdf

i made a typo on that, it should read 2.21, not 2.01!!   it is great to know that you are reading my posts in detail though. 

any yes, that link is the PDF that i am using to program my TS 60 with.

thoughts??



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