Ac Voltage Measurements; Dc Current Measurements; Resistance Measurements; Battery Replacement - Velleman DVM820 Bedienungsanleitung

4.3. AC VOLTAGE MEASUREMENTS

1. Connect the red test lead to the "V mA" jack and the black lead to the "COM" jack.
2. Place the RANGE switch in the appropriate VAC position. Set the switch to the highest range and work
your way down if the voltage range is unknown beforehand.
3. Connect the test leads to the device or circuit to be measured.
4. Activate the device or circuit to be measured. The voltage value will appear on the display.

4.4. DC CURRENT MEASUREMENTS

1. Connect the red test lead to the "V mA" jack and the black lead to the "COM" jack. (Connect the red test
lead to the "10A"-jack for measurements between 200mA and 10A).
2. Place the RANGE switch in the appropriate ADC position. Set the switch to the highest range and work
your way down if the voltage range is unknown beforehand.
3. Open the circuit to be measured and connect the test leads IN SERIES with the load of which the current is
to be measured.
4. Activate the device or circuit to be measured. The current value will appear on the display.

4.5. RESISTANCE MEASUREMENTS

1. Connect the red test lead to the "V mA" jack and the black lead to the "COM" jack.
2. Place the RANGE switch in the appropriate
3. If the resistance to be measured is connected to a circuit : disconnect the power and discharge all
capacitors prior to measurement.
4. Connect the test leads to the circuit to be measured.
5. The resistance value will be displayed.
4.6. DIODE MEASUREMENTS
1. Connect the red test lead to the "V mA" jack and the black lead to the "COM" jack.
2. Set the RANGE switch to the
3. Connect the red test lead to the anode and the black test lead to the cathode of the diode to be measured.
4. The forward voltage drop will be displayed in mV. "1" will be displayed if the polarity of the diode is reversed.
4.7. TRANSISTOR hFE-MEASUREMENTS
1. Set the RANGE switch to the hFE-position.
2. Determine whether the transistor is NPN or PNP and locate the emitter, base and collector leads. Insert the
leads into the proper holes of the hFE-socket on the front panel.
3. The display will show the approximate hFE-value at the moment of testing. Base current 10µ A, Vce 2.8V.

5. Battery Replacement

CAUTION
All test leads should be disconnected from energised circuits prior to opening the case. This eliminates the risk of
electroshocks.
- Replace the battery when the display reads
- In order to replace the batteries (2 x AAA): open the battery compartment at the back of the device. Remove the
old battery and insert new ones. Observe the polarity!
DVM820
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5 VELLEMAN