# Battery Charging



## Airboss (Jul 14, 2007)

I was wondering if it is safe to charge two 12v batteries in series with one battery charger. This would make it a lot more affordable since I already have one charger. I know what the pros are, what are the cons?

Cheers all!


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## Y-Guy (Jan 30, 2004)

12volt batteries are wired in parallel not in series, two 6v batteries are wired in series. If you wire two 12volts in series you will get 24 volts.

To answer your other question... Yes I've always charged all of my dual battery setups together to keep them balanced.


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## Ghosty (Jan 17, 2005)

Y-Guy said:


> 12volt batteries are wired in parallel not in series, two 6v batteries are wired in series. If you wire two 12volts in series you will get 24 volts.
> 
> To answer your other question... Yes I've always charged all of my dual battery setups together to keep them balanced.


X2 -- just make sure they are in parallel -- NOT SERIES


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## Airboss (Jul 14, 2007)

Okay. Thanks for putting me straight!  I think I meant parallel anyway


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## Thor (Apr 7, 2004)

Y-Guy said:


> 12volt batteries are wired in parallel not in series, two 6v batteries are wired in series. If you wire two 12volts in series you will get 24 volts.
> 
> To answer your other question... Yes I've always charged all of my dual battery setups together to keep them balanced.


x3

Thor


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## Fanatical1 (Jan 9, 2006)

Thor said:


> 12volt batteries are wired in parallel not in series, two 6v batteries are wired in series. If you wire two 12volts in series you will get 24 volts.
> 
> To answer your other question... Yes I've always charged all of my dual battery setups together to keep them balanced.


x3

Thor
[/quote]

Airboss,

Are you talking about charging the truck batteries? If so, I'm also curious if If I can use one trickle charger on the truck and to charge both batteries?
If I connect the charger to one batttery will charge both?

Mark


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## boats313 (Oct 22, 2007)

We charge 20 batteries at a time at work. 2 banks of 10 in parallel. A quick way to remember series and parallel- SAV (save) PAA (pay), Series Adds Volts, Parallel Adds Amps.


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## Airboss (Jul 14, 2007)

boats313 said:


> We charge 20 batteries at a time at work. 2 banks of 10 in parallel. A quick way to remember series and parallel- SAV (save) PAA (pay), Series Adds Volts, Parallel Adds Amps.


Brilliant! Being from a military background I just love acronyms!







Thanks for the tip.

*Fanatical1* - I was refering to the trailer batteries, but it seems that this theory would apply to the truck as well. Now here's a tricky one...If someone asks me for a jump start, which battery should I use? Or will it matter?


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## boats313 (Oct 22, 2007)

Airboss said:


> We charge 20 batteries at a time at work. 2 banks of 10 in parallel. A quick way to remember series and parallel- SAV (save) PAA (pay), Series Adds Volts, Parallel Adds Amps.


Brilliant! Being from a military background I just love acronyms!







Thanks for the tip.

*Fanatical1* - I was refering to the trailer batteries, but it seems that this theory would apply to the truck as well. Now here's a tricky one...If someone asks me for a jump start, which battery should I use? Or will it matter?
[/quote]

That's where I learned the SAV PAA, my first "C" school. 
Use the easiest battery to reach if there are 2, that's just another advantage to having a diesel. 
Eric


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