Extech Instruments 470 - Manual (Page 9)

V5.0 5/04 9
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 green
V position.
2. Press the SELECT button to
indicate “AC” on the display.
3. Insert the black test lead banana
plug into the negative COM jack.
Insert red test lead banana plug into
the positive V jack.
4. Touch the black test probe tip to the
neutral side of the circuit.
Touch the red test probe tip to the
“hot” side of the circuit.
5. Read the voltage in the display.