How to Measure a 12V Battery Cell With a Volt Meter
- 1). Clip the ends of the volt meter's two cords to the ends of the 12V battery. If the cords on your volt meter are colored, make sure the red cord is attached to the red jack opening on the meter and the black cord is attached to the black jack.
- 2). Turn on the volt meter and look at the reading on the screen. If nothing shows up, you may have attached the cords on the wrong end of the battery, so switch them.
- 3). Match the reading against the following scale. If the 12V battery is 100 percent charged, the volt meter will read 12.70. If the battery is 80 percent, it will read 12.46; if it's 60 percent, it will read 12.28; if it's 40 percent, it will read 12.12; if it's 20 percent, it will read 11.98. If the battery reads less than 12.00 voltage, it's time to either replace it or recharge it if it's a rechargeable battery.
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