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A MULTIMETER is a single meter that combines the functions of a dc ammeter, a dc voltmeter, an
ac ammeter, an ac voltmeter, and an ohmmeter. It is more convenient to have one meter with several
functions than several meters each with a single function. The various functions of a multimeter are
selected by use of the appropriate function switch positions, jacks, and meter scales. A mirror may be
used on the scale of a multimeter to eliminate parallax error.
The following SAFETY PRECAUTIONS should be observed when using a multimeter.
Deenergize and discharge the circuit completely before connecting a multimeter.
Never apply power to the circuit while measuring resistance with a multimeter.
Connect the multimeter in series with the circuit for current measurements and in parallel for
voltage measurements.
Be certain the multimeter is switched to ac before attempting to measure ac circuits.
Observe proper dc polarity when measuring dc circuits.
When you are finished with a multimeter, switch it to the OFF position, if available. If there is
no OFF position, switch the multimeter to the highest ac voltage position.
Always start with the highest voltage or current range.
Select a final range that allows a reading near the middle of the scale.
Adjust the "0 ohms" reading after changing resistance ranges and before making a resistance
measurement.
