1. Convert the electrical current needed by the device the battery will power into amps. For example, assume a device needs 550 milliamps of current. One amp contains 1,000 milliamps
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C/20 is the formula most commonly used to describe a battery according to its amp hour rating; for instance a 400Ahr rated battery means that a 20 amp load placed upon the battery
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1. Locate the specifications label on the appliance to determine what its proper voltage and current are. In this case, it's a 220 volt that draws 20 amps. 2. Divide your appliance's
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1. Examine the manufacturer's tag on the back of an appliance or other electrical device. It will either state the devices power in watts or the device's voltage (in volts, V) and
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