Measuring Frequency - HQ-Power DVM891 Manual Del Usuario

Remarks:
The meter may need a few seconds to produce a stable reading for resistance measurements in excess of
1MΩ.
The overrange indication ("1.") will appear on the display if the input is not connected or if the resistance being
measured exceeds the max. value of the selected range.
Disconnect the circuit to be tested and make sure that all capacitors are fully discharged before measuring the
in-circuit resistance.
f. Measuring Capacitance
1. Connect the test capacitor to the "Cx" input connection (9 in figure). Do NOT connect the capacitor to one of the
4 input jacks (viz. "10A", "mA", "COM" or "VΩHz" jack).
2. Select the "Cx" range with the FUNCTION switch.
Remarks:
Do not connect an external voltage to the input terminal. Discharge capacitors before connecting them.
Units: 1pF = 10
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g. Testing Diodes & Continuity
1. Connect the black test lead (-) to the "COM" jack and the red test lead (+) to the "VΩHz" jack.
2. Select the / range with the FUNCTION switch and connect the test leads.
3. Connect the red test lead to the anode and the black test lead to the cathode of the diode to be tested.
4. For continuity tests: connect the test leads to two random points of the circuit to be tested. The incorporated
buzzer is activated if the resistance between the two test leads is lower than ± 30Ω.
h. Transistor Test (hFE)
1. Select the "hFE" range with the FUNCTION switch.
2. Determine whether the transistor is of the NPN- or PNP-type and locate the emitter, the base and the collector.
Insert the leads into the proper holes in the 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.
i. Measuring Temperature
1. Measure temperatures with the K-type thermocouple: select the "T" range with the FUNCTION switch and insert
the plug of the K-thermocouple in the green "K PROBE" socket.
2. The ambient temperature will be displayed in °C if the "T" range is selected without connecting the K-
thermocouple.
Remark: Do not hesitate to push firmly in order to insert the temperature probe in the socket.
j. Measuring Frequency
1. Connect the black test lead (-) to the "COM" jack and the red test lead (+) to the "VΩHz" jack.
2. Select the "KHz" range with the FUNCTION switch and connect the test leads to the source or load to be tested.
Remarks:
Do not apply more than 220Vrms to the input.
Use shielded cable for measuring a weak signal in a noisy environment.
DVM891_v2
µ F 1nF = 10 µ F.
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- 6 - HQ POWER