Jeulin UT51, Инструкция по эксплуатации

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Measurement and instrumentation
UT51 multimeter
Ref :
291016
ENGLISH 14
™
Measuring the resistance
1. Place the Function/Range selector switch on the resistance range.
2. Turn off the power supply of the equipment to be tested and check that the
capacitors are discharged.
3. Connect the red test cord to the “V
Ω
” socket and the black test cord to the
“COM” socket.
4. Bring the probes in contact with the test points.
5. A test cord has a resistance of 0.1 to 0.3
Ω
. It is advisable to subtract the
value of these wires to obtain an accurate measurement.
6. The display takes a few seconds to stabilise when the resistance
measured exceeds 1 M
Ω
.
™
Diode test
1. Connect the red test cord to the “V
Ω
” socket and the black cord to the
“COM” socket.
2. Place the Function/Range selector switch on
3. Turn off the power supply of the circuit to be tested and check that the
capacitors are discharged.
4. Bring the probes in contact with the diode. The forward voltage drop is of
about 0.6 V (typical for a silicon diode).
6. If the diode is in an open circuit, "1" is displayed when the red test cord is
the positive terminal.
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 of less
than 1 k. In this case, disconnect the diode from the circuit to obtain an
accurate test.
™
Measuring the gain of a transistor
1. Place the Function/Range selector switch on the hFE range (PNP or NPN
transistor).
2. Never apply an external voltage on the hFE socket, as there is a risk of
damaging the device.
3. Plug in the transistor directly into the hFE slot: the sockets are marked by
E, B and C, corresponding to Transmitter, Base and Collector respectively.
4. The device directly displays the hFE value (DC gain) of the transistor.
6 Maintenance
CAUTION !! Remove the test cords before replacing the battery or the fuse or
before carrying out any other intervention.
™
Replacing the battery
The power supply is provided with a 9-volt “transistor” battery (NEDA 1604
IEC 6F22). The sign appears on the LCD screen
when this intervention is necessary. To replace the battery, remove the two
screws located at the back of the device (under the rubber stops) and
remove the battery compartment. Remove the battery from the contacts.
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