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Old 02-20-2007, 11:04 AM
  #7  
Rodney
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Join Date: Dec 2001
Location: FL
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Default RE: Wall Charger Question...

Most wall warts put out an "open circuit " voltage much higher than the batteries being charged depending on the internal resistance of the charger to limit the current. The only way to know for sure if your wall wart will charge the batteries is to put an ammeter in the circuit with the charger leads. If you get a current higher than the self discharge current, the battery will eventually become charged. You can determing the time required by dividing the battery capacity by the measured current and multiply the result by 1.6 to see how long it would take to charge a nearly discharged battery.