Dc Voltage Measurements; Ac Voltage (Frequency, Duty Cycle) Measurements - Extech Instruments EX530 User Manual

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 MODE button to indicate "Hz".
6. Read the frequency in the display.
7. Press the MODE button again to indicate "%".
8. Read the % of duty cycle in the display.
6 EX530-EU_ENG V3.4 1/08