Elenco 3 1/2 Digit with Temperature - Manual (Page 23)

Testing Diodes
Caution
To avoid possible damage to the meter or to the equipment
under test, disconnect the circuit power and discharge all
high-voltage capacitors before testing diodes.
Use the diode test to check diodes, transistors, silicon controlled
rectifiers (SCRs), and other semiconductor devices. The test sends
a current through a semiconductor junction, then measures the
junction’s voltage drop. A typical junction drops 0.5V to 0.8V.
To test a diode out of a circuit, set up the meter as shown in Figure
11. In a circuit, a similar diode should still indicate 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.
Figure 11. Diode Test
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