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5-9-2 Diode (
) test
1)
What to measure
(Diode test): Judging the diode (Good or defective)
2)
Measuring procedure
①
Connect the red plug of the test lead to
measuring
terminal and the black one to the COM terminal.
②
Set the function selector to
, then press the SELECT
button to select the diode test.
(The sub display shows [diod
].)
③
Apply the black test pin to the cathode of the diode, and the
red one to the anode.
④
The display will show the forward voltage drop (forward
biased).
*
Forward biased voltage drop for a good silicon diode is
between 0.400 V to 0.900 V. A reading higher than that
indicates a defective diode. A zero (or close to)reading
indicates a defective diode (shorted). An OL indicates a
defective diode (open).
⑤
Apply the red test pin to the cathode of the diode, and the
black one to the anode.
*
A reading [OL
] for reverse biased voltage drop indicates
the diode is good. Any other readings indicate the diode is
defective (resistive or shorted).
Note:
・
Open circuit voltage between the measuring terminals: <3.5 V dc
・
Test current: 0.4 mA (typical)
・
Diode test function does not show the bar graph.
Forward biased test
Reverse biased test