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Old November 27th 03, 05:09 PM
Bruce W...1
 
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Rick Frazier wrote:

Bruce:

Did you measure the voltage with the charger connected, or after you removed
it?
A standard 12v lead-acid automotive battery has a nominal voltage of 12.6
volts. Even after a float charge, once the charging current is removed, the
battery will return to about 12.6 volts fairly rapidly. Thus, the voltage
you measured would be considered normal for a charged battery.

While the trickle charger is connected to the battery, any current in excess
of that needed to fully charge the battery is converted to heat. You will
only read the charging voltage when the charger is actually connected and
operating. about 10ma of the current is going into the loads you've already
measured, with the rest going to keeping the battery at top charge.

Unless you are measuring the voltage with the charger connected, you
probably don't need to have one with more current.

--Rick

================================================== ===========

The battery measured 12.7V both with and without the charger connected.
So the charger (putting out 13.7V and 500mA) doesn't have enough juice,
er current, to change this. So right now 500mA is being converted to
heat.

This begs the question, what then is the point in regulating the charge
voltage to 13.3V (or 14.2V at freezing temperatures)? Wouldn't a
charger regulated at say 12.9V do just as well at keeping a full charge?

This comes full circle on my original thread postulation. There is NO
point in regulating the voltage, just connect a properly sized wall wart
and you're done. The proof is right here.