Omega HHM32, Руководство пользователя

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12
Diode Tests
1. Connect the red test lead to the "V
W
" jack and the black test lead to the
"COM" jack.
2. Set the Function/Range switch to the " " position.
3. Turn off power to the circuit under test.
4. Touch probes to the diode. A forward-voltage drop is about 0.6V (typical for
a silicon diode).
5. Reverse probes. If the diode is good, "OL" is displayed. If the diode is
shorted, ".000" or another number is displayed.
6. If the diode is open, "OL" is displayed in both directions.
7. If the junction is measured in a circuit and a low reading is obtained with both
lead connections, the junction may be shunted by a resistance of less than
1k
W
. In this case the diode must be disconnected from the circuit for
accurate testing.
8.In continuity test, the beeper sounds continuously, if the bargraph number
is less than 3 counts.
Transistor Gain Measurements
1. Set the Function/Range switch to the desired h
FE
range (PNP or NPN type
transistor).
2. Never apply an external voltage to the h
FE
sockets. Damage to the meter
may result.
3. Plug the transistor directly into the h
FE
socket. The sockets are labeled E,
B, and C for emitter, base, and collector.
4. Read the transistor h
FE
(dc gain) directly from the display.