Measuring DC Voltage
Most portable electronics are powered by direct current (DC) voltage
sources. Batteries are a prime example of this, and the multimeter
can be used to measure how many volts are being output.
For example, you’ve found some AA batteries lying in the bottom of a
drawer, and you’re unsure if they’re new or used. Before you dispose
of them (responsibly of course), follow the instructions below to see if
they’re still usable.
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. As we are checking for the voltage in
a 1.5V AA battery, set the mode dial to
the 2 VDC setting.
Note:
The ‘200m’ setting would result in
an overrange indicator or ‘OL’ to display
on screen if the battery is new and still
outputting 1.5V.
The rule of thumb is to round the
measurement up to the next available
mode setting. So for a 2.3V power
source, set the mode dial to ‘20’ and so
on.
Note:
If you are unsure of the voltage you are about to measure,
set the mode dial to 200 or 300 VDC. Refer to the ‘Finding The
Measuring Range’ in ‘2. CONTROLS’ section for more detail.
3. Press the black test probe to
the negative terminal of the
battery (marked ‘-’) and the
red test probe to the positive
terminal (marked ‘+’).
4. If the battery is new, a reading
of around ±1.500V will display
on screen. If a negative ‘-’ sign
shows up onscreen you have
just pressed the probes to the
opposite ends of the battery.
Measuring AC Voltage
The electricity supplied to homes is in the form of alternating current
(AC). This multimeter could be used to check wall outlets with the
right accessories and knowledge.
WARNING!
CHECKING WALL FIXTURES REQUIRES
LIVE CIRCUITRY WHICH CAN BE EXTREMELY
DANGEROUS. ONLY PERFORM THIS IF YOU
ARE ABSOLUTELY SURE OF WHAT YOU’RE
DOING. CONSULT A QUALIFIED, PROFESSIONAL
ELECTRICIAN INSTEAD IF YOU HAVE ANY DOUBT.
WARNING!
NEVER TOUCH THE BARE METAL
PORTION OF THE PROBES. DOING SO COULD
CAUSE AN ELECTRICAL SHORT AND RESULT IN
ELECTROCUTION, INJURY OR EVEN DEATH.
WARNING!
ENSURE THAT THE PROBE WIRES
AREN’T FRAYED, THE INSULATION IS INTACT AND
THE PROBE ENDS ARE NOT LOOSE OR WOBBLY.
WARNING!
WEAR RUBBER SOLED SHOES,
INSULATING GLOVES AND SUITABLE PROTECTIVE
EQUIPMENT WHEN WORKING WITH LIVE CIRCUITS.
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 appropriate
VAC range.
3. Connect the test leads across the source or circuit to obtain a
measurement.
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
3. VOLTAGE
WARNING!
TO AVOID ELECTRIC SHOCK OR
DAMAGE TO THE METER, DO NOT ATTEMPT TO
MEASURE CIRCUITS OR POWER SUPPLIES THAT
OUTPUT MORE THAN 300V (AC OR DC).
WARNING!
POWER SUPPLIES IN CIRCUITS
THAT HAVE BEEN ‘SWITCHED OFF’ CAN STILL
OUTPUT A VOLTAGE WHEN MEASURED WITH THE
MULTIMETER.
