Ac Voltage Measurements; Dc Voltage Measurements - Extech Instruments EX320 User Manual

AC VOLTAGE MEASUREMENTS

WARNING: Risk of Electrocution. The probe tips may not be long enough to contact the
live parts inside some 240V outlets for appliances because the contacts are recessed
deep in the outlets. As a result, the reading may show 0 volts when the outlet actually
has voltage on it. Make sure the probe tips are touching the metal contacts inside the
outlet before assuming that no voltage is present.
CAUTION: Do not measure AC voltages if a motor on the circuit is being switched ON
or OFF. Large voltage surges may occur that can damage the meter.
1. Set the function switch to the VAC position.
2. Insert the black test lead banana plug into
the negative COM jack. Insert red test lead
banana plug into the positive V jack.
3. Touch the black test probe tip to the neutral
side of the circuit.
4. Touch the red test probe tip to the "hot" side
of circuit.
5. Read the voltage in the display.

DC VOLTAGE MEASUREMENTS

CAUTION: Do not measure DC voltages if a motor on the circuit is being switched ON
or OFF. Large voltage surges may occur that can damage the meter.
1. Set the function switch to the VDC position.
2. Insert the black test lead banana plug into the
negative COM jack.
Insert the red test lead banana plug into the
positive V jack.
3. Touch the black test probe tip to the negative
side of the circuit.
Touch the red test probe tip to the positive side
of the circuit.
4. Read the voltage in the display.
EX320-EU-ENG V5.1 6/09
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