Testing Diodes; Transistor Test (Hfe) - Velleman DVM630 Mode D'emploi

7.7 Testing Diodes

To avoid electrical shock and/or damage to the instrument,
disconnect the circuit power and discharge all high-voltage capacitors
before testing diodes.
Never perform diode measurements on a live circuit.
To test a diode out of a circuit:
1. Set the rotary switch to the
2. Connect the black test lead to the "COM" socket and the red test lead to
the "VΩmAhFE" socket.
3. Connect the black test probe to the cathode (negative); connect the red
test probe to the anode (positive) of the diode.
The meter displays the approximate forward voltage drop. If the probe
connection is reversed, the meter displays "1".
Notes:
Measuring diodes that are part of a circuit might produce faulty results.
Consider disconnecting them from the circuit.
In a circuit, a good diode should produce a forward bias reading of 0.5 V
to 0.8 V. However, the reverse bias reading can vary depending on the
resistance of other pathways between the probe tips.
7.8 Audible Continuity Test
To avoid electrical shock and/or damage to the instrument,
disconnect the circuit power and discharge all high-voltage capacitors
before testing the continuity.
Never perform continuity tests on a live circuit.
To test for continuity:
1. Set the rotary switch to the
2. Connect the black test lead to the "COM" socket and the red test lead to
the "VΩmAhFE" socket.
3. Connect the test probes to the circuit/component under test.
If the measured resistance is less than ± 100 Ω, the buzzer sounds
continuously and the resistance is displayed. If the measured resistance
exceeds 2 kΩ or in case of an open circuit, the display shows "1".

7.9 Transistor Test (hFE)

To avoid electrical shock and/or damage to the instrument, do not
apply more than 250 VDC or 250 VAC rms between the COM
terminal and the "VΩmAhFE" terminal.
Use the included adaptor socket.
V. 01 – 22/04/2013
DVM630
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