24v battery bank not the same voltage ,

[joshhopey]

hi i got 8 batteries in series 12v each to make 24v ,
when charging , the batteries voltage when testing the 12v voltage
1 battery is 12.93 and the 2nd battery is 13:10 , but when you check the two batteries in series , to make 24v , they the same as the rest off the bank , is this normal for 24v bank ? do you recommend battery battery balancer for them ? like theses http://www.ebay.co.uk/itm/24V-Solar-...UAAOSwNRdX~2bu

[Sunking]

hi i got 8 batteries in series 12v each to make 24v ,

No you do not, or I should say you had better not have them all wired in series. If you have 8 - 12 volt batteries wired in series, you have 96 Volts. The only way to use 8 - 12 volt batteries to make 24 volts is a 2S4P configuration. That means 2 in series per string, and 4 parallel strings.

when charging , the batteries voltage when testing the 12v voltage
1 battery is 12.93 and the 2nd battery is 13:10 , but when you check the two batteries in series , to make 24v , they the same as the rest off the bank , is this normal for 24v bank ? do you recommend battery battery balancer for them ?

This suggest to me you just might have all 8 batteries wired in series. Would explain your question and confusion.

Your batteries should be wired as shown below, just add 2 more strings to make 4 parallel strings That is 2 in series, 4 in parallel aka 2S4P or 2 x 4. You do not need anything other than to learn what you are doing.

[joshhopey]

No you do not, or I should say you had better not have them all wired in series. If you have 8 - 12 volt batteries wired in series, you have 96 Volts. The only way to use 8 - 12 volt batteries to make 24 volts is a 2S4P configuration. That means 2 in series per string, and 4 parallel strings.





This suggest to me you just might have all 8 batteries wired in series. Would explain your question and confusion.

Your batteries should be wired as shown below, just add 2 more strings to make 4 parallel strings That is 2 in series, 4 in parallel aka 2S4P or 2 x 4. You do not need anything other than to learn what you are doing.

hi thanks for replay sorry forgot to say it series and parallel , it just one battery atm resting is 12:53 and the other one is at 12:61 ? is that okay > note they are in series . and parallel , im wondering if you got skype so i could show you a video off it , many thanks my skype is joshhopey

[Sunking]

hi thanks for replay sorry forgot to say it series and parallel , it just one battery atm resting is 12:53 and the other one is at 12:61 ? is that okay > note they are in series . and parallel , im wondering if you got skype so i could show you a video off it , many thanks my skype is joshhopey

That says you need to EQ the batteries with your generator and battery charger. Cannot be done with Solar. You need a stiff source of power for 24 hours. Solar cannot do that as it only provides full power for 1 hour or less.

[joshhopey]

That says you need to EQ the batteries with your generator and battery charger. Cannot be done with Solar. You need a stiff source of power for 24 hours. Solar cannot do that as it only provides full power for 1 hour or less.

hi mate i dont have alot off money will this battery charger work say im only 19 im still new to this http://www.ebay.co.uk/itm/10AMP-12V-...IAAOSw~gRVu2~i

[John Galt 1]

How long have the batteries been resting before checking the voltage? You really need to let them rest at least 4 hours and overnight is better if you intend to use voltage as the testing method.
If these are LA (lead acid) batteries a hydrometer is a much more accurate way to test their condition.
If you do decide to equalize them please don't EQ them for 24 hours. If they don't come back within 1-4 hours they aren't going to get any better and a 24hr EQ will seriously reduce their life. And yes, solar is capable of holding a several hour EQ on a sunny day if you've got enough panels to hold the EQ voltage. Using solar to equalize during short winter days can be harder.

[joshhopey]

How long have the batteries been resting before checking the voltage? You really need to let them rest at least 4 hours and overnight is better if you intend to use voltage as the testing method.
If these are LA (lead acid) batteries a hydrometer is a much more accurate way to test their condition.
If you do decide to equalize them please don't EQ them for 24 hours. If they don't come back within 1-4 hours they aren't going to get any better and a 24hr EQ will seriously reduce their life. And yes, solar is capable of holding a several hour EQ on a sunny day if you've got enough panels to hold the EQ voltage. Using solar to equalize during short winter days can be harder.

hi john they been resting for 42 hours , no voltage drop . im just ordered a 20 amp 24v battery charger and i will leave it on charge for 24 hours , i installed two new batteries and then it came out off balance hopefully onced i charged it on mains it should sort it self out