JEFDMM300V
300V
DIGITAL MULTIMETER
USER GUIDE
v.1.1
MEASURING DC CURRENT
1a. For current measurements less than 200mA:
Connect the black test lead to the
COM
terminal and the red lead to the
VΩmA
terminal.
1b. For current measurements between 200mA and 10A:
Connect the black test lead to the
COM
terminal and the red lead to the
10A
terminal.
2.
Set the
Function / Range
switch to the desired
range position. If the
magnitude of the current is not known before hand you can set the range
to the highest range first and then reduce it range by range until a suitable
resolution is obtained.
3.
Turn off the power to the circuit you need to measure then discharge all
capacitors of the circuit.
4.
Break the circuit path to be measured and connect the test leads in
series with the circuit.
5.
Check the DC Current reading on the display. The polarity of the red test
lead connection will also be indicated.
MEASURING RESISTANCE
Before measuring in-circuit resistance, disconnect all power to the circuit
to be tested and discharge all capacitors thoroughly.
1.
Connect the black test lead to the
COM
terminal and the red lead to the
VΩmA
terminal.
2.
Set the
Function / Range
switch to the desired
Ω
range position.
3.
Connect the test leads across the equipment to be tested.
4.
Check the resistance reading on the display.
Note:
For measurements > 1000kΩ, the meter may take a few seconds
to stabilize the reading. This is normal for high resistance measurements.
When the input is not connected, i.e at open circuit, “
1
” will be displayed
as an over-range indication.
CONTINUITY TESTING
Before measuring the continuity, disconnect all power to the circuit to be
tested and discharge all capacitors thoroughly.
1.
Connect the black test lead to the
COM
terminal and the red lead to the
VΩmA
terminal.
2.
Set the
Function / Range
switch to the
setting.
3.
Connect the test leads across the circuit to be measured.
4.
If the resistance is lower than about 30Ω, the built in buzzer will sound.
DIODE TESTING
1.
Connect the black test lead to the
COM
terminal and the red lead to the
VΩmA
terminal. Note the polarity of the red test lead is positive “
+
”
2.
Set the
Function / Range
switch to the
setting.
3.
Connect the red test lead to the anode of the diode to be tested and the
black test lead to the cathode of the diode.
4.
The display will show the approximate forward voltage drop of the
diode. If the connection is reversed, then only the reading “
1
” will be
shown on the display.
Max Open Circuit Voltage:
Approx 2.8V
DC Current
Resistance
Continuity & Diode Testing