Mastech ms8217, User Manual

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Ω
3.2.3 Diode Test
To avoid electrical shock and/or damage to the
instrument, disconnect circuit power and
discharge all high-voltage capacitors before
testing diodes.
Warning
Use the diode test to check diodes, transistors, and other
semiconductor devices. The diode test sends a current
through the semiconductor junction, then measures the
voltage drop across the junction, A good silicon junction
drops between 0.5V and 0.8V.
The Meter's resistance ranges are 400.0Ω, 4.000kΩ,
40.00kΩ, 400.0kΩ, 4.000MΩ and 40.00MΩ.
To test a diode out of a circuit (set up the Meter as shown
in Figure 4):
1. Set the rotary switch to range.
2. Press the yellow key once to activate Diode Test.
3. Connect the black and red test leads to the COM and
VΩ terminals respectively.
4. For forward-bias readings on any semiconductor
component, place the red test lead on the component's
anode and place the black test lead on the component's
cathode.
5. The meter will show the approx. forward voltage of the
diode.
In a circuit, a good diode should still produce a forward
bias reading of 0.5V to 0.8V; however, the reverse-bias
reading can vary depending on the resistance of other
pathways between the probe tips.
DIGITAL MULTIMETER DIGITAL MULTIMETER