A digital multimeter is used to measure voltage, current and resistance and can be used to measure electrical continuity in a circuit. The digital display on the multimeter shows the numerical measured value of voltage, current or resistance. A multimeter should be calibrated or adjusted to a known zero-value prior to use for accurate readings.

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Multimeter calibration

Step 1

Set the multimeter to the highest resistance range by turning the dial to the highest "ohm" setting.

Step 2

Touch the test probes of your digital multimeter together. The digital display of the multimeter should read "0 ohms."

Step 3

Press the calibration knob until the display reads "0" on the digital multimeter if you don't see "0 ohms" initially.