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DieHard Battery Charger Instructions

by Daisy Cuinn

A DieHard electric battery charger allows you to recharge without having another car present. It takes longer, but is simple and requires only an AC outlet. Always make sure that the charger is designed to work with your battery's voltage. Most cars use a 12-volt battery.

Set the battery charger to the correct voltage, usually 12 volts for a car.

Switch the output selector to the desired number of amps. The lower the number of amps, the longer it takes to charge.

Attach the positive battery charger clamp to the positive post first for batteries that are negative-grounded, as most car batteries are. Attach the negative battery charger clamp to the negative post.

Plug the battery charger into a grounded outlet. Charge the battery until the ammeter needle indicates that the battery is charged. Unplug the charger when the ammeter indicates a full charge. Remove the clamps, negative first.


  • If the charger has a 200-amp "jump start" setting, connect as directed and try starting the car after about a minute.
  • Most car batteries take between two and three hours to charge at 10 amps.


  • Do not allow the battery to overcharge.
  • If you need to use an extension cord, use only a heavy-duty three-pronged type.
  • Turn your head when connecting and disconnecting clamps, in case of a spark.

Items you will need

About the Author

Delaware-based Daisy Cuinn has been writing professionally since 1997, when she became the features editor for her local biweekly music newspaper. She has been a staff writer and contributor to online and offline magazines, including "What It Is!," and Slashfood. Cuinn holds a Bachelor of Fine Arts from Temple University.

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