Extech Instruments EX520 Drums User Manual


 
EX520-en-GB_ v2.7 4/15
6
Operating Instructions
WARNING: Risk of electrocution. High-voltage circuits, both AC and DC, are very dangerous and
should be measured with great care.
1. ALWAYS turn the function switch to the OFF position when the meter is not in use.
2. If “OL” appears in the display during a measurement, the value exceeds the range you have
selected. Change to a higher range.
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 green 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.
AC VOLTAGE (FREQUENCY, DUTY CYCLE) 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 VAC/Hz/% 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. Touch
the red test probe tip to the “hot” side of the circuit.
4. Read the voltage in the display.
5. Press the HZ/% button to indicate “Hz”.
6. Read the frequency in the display.
7. Press the Hz/% button again to indicate “%”.
8. Read the % of duty cycle in the display.