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1
Diode Test
1. Set the function switch to
range position.
2. Press the
MODE
button to select the Diode Test range.
The meter automatically defaults to Resistance.
3. Insert the red test lead into the “
V Ω TEMP HZ
” input terminal
and the black lead to the “
COM
” terminal.
4. Connect the other end of the test leads to the component under test.
Read the display.
Notes:
• Use the diode test to check diodes, transistors, silicon controlled
rectifiers (SCR’s) and other semiconductor devices
• The test sends a current through a semiconductor junction,
then measures the junction’s voltage drop.
• Normal forward voltage drop (forward bias) for a good silicon diode
is between 0.4V to 0.9V. A reading higher than that indicates a leaky
(defective) diode. A zero reading indicates a shorted diode.
• Reverse the test leads connection (reverse bias) across the diode.
The display shows “
OL
” if the diode is good. Any other readings
indicate the diode is shorted or resistive (Defective).