How to Test Deep-Cycle Batteries With a Volt Meter
- 1). Set the voltmeter to the appropriate range unless the voltmeter self-selects the range and type of voltage. Deep-cycle boat batteries provide DC current from zero to 24 volts.
- 2). Bleed the residual charge from the battery by turning on your boat's lights, radio and electronics for one minute.
- 3). Turn the lights and other electrical and electronic devices off. Touch the red probe to the positive post of the battery and the black probe to the negative post of the battery, making good contact with both posts.
- 4). Read the voltage of your battery on the voltmeter display.
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