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Old 03-27-2012, 05:54 AM   #23
JD
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RE: Comments on Changing by Battery arrangement

Quote:
timjet wrote:FF wrote:
I understood the better dock chargers had selection to lower the charge Voltage for AGM and gell.
*You mean increase the voltage for AGM and Gell. Yes this is true of mine as well. However my 3 bank charger allows one selection for all 3 banks. I don't know of any charger that will allow you to charge banks and different voltages.

*One thing you could do is find an old isolater.* An isolator uses a diode to keep the current from going in two directions.* That will drop the voltage .5V down stream from what is going in. But I'm not sure that is needed.

If you go to four different sites you get four different answers and this is all*from battery manafactuers.* Bottom line is AGMs Charge from between 14.2 V*- 14.8 V depending on who wrote the article.* Wet cells are in the same range 14.4 V*- 14.9 V again depending on who you believe.* So I'm not sure the charge voltage is the issue.* Float rate varies about the same as well.**So it seems that 14.4 V*-*14.6 V makes everyone happy as a charge rate for both types and with an adjustable regulator you should be able to get there.* I did find an article that explains the real problem with mixing them and in fact makes sense.

"Mixing Batteries

The reasons we do not recommend wet cell and AGM Batteries together are:

When charging, the AGM will reach full charge before the wet cell. This means that the charge system will do one of two things. It will keep charging until the wet cell is fully charged and may over-charge the AGM or it will switch off when the AGM is fully charged which means the wet cell is only partially charged.

The advantage of having 2 AGM batteries is that both can be used for starting or house use in an emergency and quicker charging means less drag on the alternator."

In my mind we are only talking one AGM here so just bite the bullet and get one.* You already have the major cost done with the for house bank AGMs.
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