Measuring Resistance
Most resistors have colour codes on them to help you work out their
values, however an easier method is just to use the multimeter to
measure them.
1. Connect the black test lead
to the black ‘COM’ port
and the red test lead to
the red ‘VmAΩ’ port on the
multimeter.
2. Set the mode dial to the 2M Ω setting.
3. Press a probe to each lead on
the resistor. It doesn’t matter
which direction, as resistors
do not have polarity (‘+’ or ‘-’
sides).
4. The meter will display one of three things: ‘OL’, ‘0’ or the resistor
value.
- If ‘OL’ appears, the resistor is larger than 2MΩ and out of the
multimeter range.
- If ‘0’ appears you need to lower the mode dial setting before
repeating the measurement.
- If the display shows some value such as 0.06, that means the
resistor is 0.06MΩ or about 60kΩ. You can adjust the mode dial to
the 200k Ω setting for better resolution.
Note:
For measurements >1MΩ, the meter may take a few seconds
to stabilise.
Measuring DC Current
Unlike measuring voltage and resistance, you will have to physically
interrupt the circuit and connect the multimeter in series with the
components. A pair of alligator clip test probes (not supplied) are
recommended to make this operation easier.
1. Connect the black test lead to
the black ‘COM’ port.
2. Connect the red test lead to
the blue ‘10A’ port and set
the mode dial to the 10A ADC
setting.
WARNING!
WHEN THE RED TEST LEAD IS PLUGGED
INTO THE ‘10A’ PORT, THE MODE DIAL MUST BE
SET TO ‘10A’ OR LEFT IN THE ‘OFF’ POSITION.
Note:
When measuring circuits with
small currents under 200mA, the red
test lead may be plugged into the red
‘VmAΩ’ port instead. In which case do
not set the mode dial to ‘10A’, rather
follow the procedure for finding the
measuring range mentioned previously.
3. Switch off the power in the circuit under scrutiny and discharge all
capacitors if there are any.
4. Disconnect the negative lead
of the last item in the circuit
from the negative terminal
of the battery and secure it
to the red test probe of the
multimeter. Here is where the
alligator clips come in handy.
5. Connect the black test
probe of the multimeter to
the negative terminal of the
battery.
WARNING!
CONNECT THE METER ON THE GROUND
SIDE OF THE CIRCUIT TO AVOID ACCIDENTALLY
CREATING AN ELECTRICAL SHORT WHICH CAN
BLOW THE FUSES IN YOUR MULTIMETER.
6. Switch the circuit on and read the display for the current.
Note:
The current measurement may fluctuate over time. It is
recommended to take an average of the readings.
7. When finished with the measurement, power down the circuit,
switch off the multimeter and disconnect the leads.
WARNING!
DO NOT LEAVE THE MODE DIAL IN
ANY OF THE ADC SETTINGS. TAKING A VOLTAGE
READING OVER A POWER SOURCE IN THIS
STATE WILL CREATE A SHORT CIRCUIT IN YOUR
MULTIMETER AND BLOW THE FUSE IN THE UNIT.
A
V
~
300
300
20
200
200
2
200m
Ω
OFF
200
200µ
20µ
2k
20k
200k
200m
20m
2m
2M
10A
VmA
Ω
V
10A
COM
A
V
~
300
300
20
200
200
2
200m
Ω
OFF
200
200µ
20µ
2k
20k
200k
200m
20m
2m
2M
10A
VmA
Ω
V
10A
COM
+
-
A
V
~
300
300
20
200
200
2
200m
Ω
OFF
200
200µ
20µ
2k
20k
200k
200m
20m
2m
2M
10A
VmA
Ω
V
10A
COM
A
V
~
300
300
20
200
200
2
200m
Ω
OFF
200
200µ
20µ
2k
20k
200k
200m
20m
2m
2M
10A
VmA
Ω
V
10A
COM
A
V
~
300
300
20
200
200
2
200m
Ω
OFF
200
200µ
20µ
2k
20k
200k
200m
20m
2m
2M
10A
VmA
Ω
V
10A
COM
A
V
~
300
300
20
200
200
2
200m
Ω
OFF
200
200µ
20µ
2k
20k
200k
200m
20m
2m
2M
10A
VmA
Ω
V
10A
COM
ODMM-300
4. RESISTANCE
5. CURRENT
