How to Use a Digital Multimeter and Why
A digital multimeter is preferred because it is more accurate in giving data with decimals and it can also measure capacitance and frequency.
25/07/2020
A multimeter is a tool that helps to measure
electricity in terms of voltage, current, and
resistance. Voltage is the measure of how strong
the electricity is moving in a circuit and is
measured using volts. Current is the amount of
electricity that is flowing through the circuit
and is measured using amperes. Resistance is the
measure of how hard it is for electricity to
flow and is measured using ohms.
Discovered in the 1920s, multimeters have been
used to diagnose electrical problems. There are
two types of multimeters, the analog, and
digital types. The digital type is preferred
because it is more accurate in giving data with
decimals and it can also measure capacitance and
frequency.
The Advantages and Drawbacks
The advantage of the digital multimeter over
the analog type is that it is more accurate than
the analog multimeter because they have a
numerical display rather than the pointer in the
analog type. This, therefore, helps to minimize
errors in data reading and interpretation. The
digital multimeters have no shock failures
because their displays do not have moving parts.
They have a faster reading speed and, therefore,
increase convenience.
You also do not
have to adjust the digital multimeter to zero as
you would need to when using the analog type. As
you see on
https://www.gadgetsspy.com/best-multimeters/,
the digital multimeter has an auto-polarity
function which prevents you from connecting it
to the circuit that has the wrong polarity. They
also have an auto-ranging function which
prevents the damage that would happen if the
wrong range is used.
Some of the
drawbacks of digital multimeters are that they
are more expensive than the analog type. They
are also unable to read fluctuations in the
measurements. If the voltage has exceeded the
limit which the digital multimeters can work at,
they become damaged. They also depend on
batteries or external power to function and can,
therefore, fail if these are unavailable.
Overheating can damage them and give wrong
readings.
How Does the Digital Multimeter Work?
The multimeter has four parts -- the display,
the selection knob, the ports, and the probes.
The display is the area where you read the
measurements from. The display normally shows 4
digits and can display decimals and negative
signs. The selection knob helps you to choose
what you want to measure, whether it is the
current, the voltage, or the resistance.
The probes are plugged into the ports. The COM
port is where the black probe is inserted and is
used for earthing. The red probe is attached to
any other port, depending on what you are
measuring. The red and the black probes have no
difference except the color. A banana plug on
the probes enables them to be connected to the
multimeter.
There are
two types of
current that you can measure, the direct (DC) or
the alternating current (AC). Direct current,
which flows in one direction, is the type of
current in the AA and AAA batteries, while the
alternating current is the type that changes
direction multiple times in a second and is
found in the wall outlets.
While measuring the voltage, set the mode on
the straight line for the DC. For the AC, use
the one on the wavy line. Connect the red port
to the port that is marked with a V on the
positive side, which is the direction where the
current is flowing from. The COM probe should be
connected on the other side. Ensure that you
have placed the probes alongside the leads on
where you are measuring the voltage so that they
are in parallel. You can then read the
measurements from the display.
When
measuring the resistance, ensure that the red
probe is in the port for resistance. Connect the
probes to the resistor leads and read the
results. To measure the current, the multimeter
should be in series with the red probe on the
component and the black probe next to it. To
check for continuity, connect the probes to tips
of wires. If there is continuity, you will hear
a continuous sound, but in the lack of
continuity, no sound is produced.
Why Should You Learn to Use a Digital Multimeter?
When you learn to
use a multimeter, you can
test your batteries. When measuring the voltage,
a new battery will have a voltage that exceeds
that which it's rated at. You can also use a
multimeter to test the electrical outlets. It
also helps you to check if your wall switch is
working. The digital multimeters will help you
measure the temperature of your appliances and
also to test extension cords.
You should
be careful when handling a multimeter by placing
your hands on the plastic and rubber parts and
avoiding the metal parts that have energy. Use
safety glasses to protect yourself in the event
of a flash. If you are not experienced in
handling electrical appliances, use the system
that does not have live electricity to avoid
electrical shock and burns. Watch out for
overheating and damage of the multimeter as it
can give you incorrect readings.
Digital multimeters measure the
electrical voltage, current, resistance,
capacitance, and frequency and will help you to
text batteries, switches, and extension cables
as well as reading the temperature of your
devices. You should familiarize yourself with
the components of a multimeter and how to use
it.