Measurement and instrumentation
CL 3020 multimeter
Ref : 291 175
ENGLISH
16
3.5 Measuring resistance and continuity
1. Place the Function/Range selector switch on the desired resistance or
continuity range.
2. Disconnect the power supply of the equipment to be tested.
3. Connect the red test cord to the “V
”
socket and the black test cord to the
“COM” socket.
4. Bring the probes in contact with the test points. In the Ohms range, the
displayed value corresponds to the value of the resistance measured.
In
continuity test mode, the buzzer emits a continuous audible signal if the
resistance is less than
40
+/- 20
.
5. Case when the 400 M
range is used:
this range includes an offset of
2.0+/-0.1 counts in the value read. When the ends are short circuited in this
range, the device displays 02.0. This residual value must be subtracted from
the value obtained in step 4. For example, if we measure 110.0 M
in the
400.0 M
range, the display indicates 112.0 and the 2.0 residuals must be
subtracted to obtain the actual value of the resistance, that is 110.0 M
.
3.6 Diode test
1. Connect the red test cord to the “V
”
socket and the black cord to the
“COM” socket.
2. Place the Function/Rang
e selector switch on “
”
3. Disconnect the power supply of the circuit to be tested.
4. Bring the probes in contact with the diode. The forward voltage drop is of
about 0.6 V (typical for a silicon diode).
5. Reverse the probes. If the diode is functioning correctly, the display will
indicate a value between 2.800 V and 3.200 V. If the diode is short circuited,
"000" or any other number will be displayed.
6. If the diode is in an open circuit, the display will indicate a value between
2.800V and 3.200 V in both directions.
7. If we measure the junction in a circuit and obtain a low value for the two
connections, it could be that the junction is shunted by a resistance less than
1 k
. In this case, disconnect the diode from the circuit to obtain an accurate
test.
3.7 Measuring frequencies
1. Place the Function/Range selector switch on 4000 Hz.
2. Connect the red test cord to the “V
”
socket and the black test cord to the
“COM” socket.
3. Connect the test cords on the measuring points and read the frequency on
the display.
