How Does a Multimeter Work?

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You probably have heard about the multimeter but have no idea on how it exactly operates. Well, in this article, you will be taken through everything there is to know about how this device works.

A multimeter is a handheld device that chains different electronic analysis and is also used in measuring current, resistance as well as voltage. Some of the more advanced multimeters can also be used in measuring inductance, capacitance, and temperature. Moreover, they can also be used in measuring the duty cycle and frequency.

Main components

So what are the essential parts of a multimeter? Well, read through this article and get an in-depth understanding of this tool’s most important components that will help you understand how to make use of it. 

Power source

The multimeter gets its power from the battery. Typically, small units only need a single battery of 1/2 volt AA cell while larger multimeters that can perform several functions require a nine-volt battery.


Controls are meant to permit you to choose the desired measurement such as voltage, resistance as well as current. The dial is the main control that you are required to twist when choosing what you want to examine.

Additionally, the hand switches, as well as the buttons, are used either as secondary or primary controls, thereby enabling you to select a wide range of the reading values you as you desire. Integrated into the multimeter are different circuits for getting numerous measurements, so the controls guide you in choosing that which is functioning correctly. 


A multimeter has a very vital part known as a monochrome LCD screen which is usually digital. This part is responsible for displaying the reading value given by the multimeter in numbers to three or two decimal places. Furthermore, it has icons for showing settings.

However, older multimeter models come with a dial display as well as a needle showing the reading values found, whereas modern multimeters have larger screen displays hence allowing you to read the values being be displayed graphically in a waveform and numbers.


These usually act as insulated metals that can be able to be attached to components and wires, they are red and black. The red probe represents positive while the black probe represents negative. Probes take a long section of the exposed pieces of metals which secures component leads as well as wires through twisting.

This also encourages you to take the readings with your hands freely. Additionally, probes are also well known for examining non-electronic reading values such as pH and temperature.

As mentioned before a digital multimeter can be used to measure; temperature, resistance, capacitance, frequency, DC as well as AC voltage and current. Nevertheless, this all depends on the model of the multimeter you have, but with any variety of the digital multimeter, you can measure resistance, voltage, and current.

The most popular use of a multimeter is to measure voltage. Below are some basic procedures that will enable you to run your test on different circuits with a multimeter to get voltage; 

Alternating current circuit (AC)

nstall your test leads into an appropriate terminal of the multimeter and then in the port with label V, install the red lead while in a common port (COM) install the black lead. Consequently, switch on your multimeter and position your selector switch to a port labeled V which has a wave. Because it is AC, how you position your leads does not mater but have a clue on the readings you expect to obtain from the measurements.

Direct current circuit (DC)

The installation of the test leads to the correct terminals also applies here, as you need to place the red lead into the port with a symbol V and the black lead to a COM (common) port.

Switch your multimeter on as well as your selector switch located on the port labeled V with a dashed line plus a solid (VDC).

Subsequently, connect the test leads to the circuit on the positive point that has a full potential, connecting to the red lead while on the negative side that has equal potential connected to the black lea, with this the circuit ground.

Afterward, observe the reading value displayed on your multimeter screen, with this reading showing the real voltage of your circuit. In case you observe a symbol after your reading value, you are required to switch your entire lead since this is a sign that your polarity is backward. If any reading is not being displayed, ensure that you choose the appropriate settings and the leads.

Confirm that the leads are connected properly. In case you do not see the reading anymore, consider either your circuit being dead or your circuit is off. Additionally, if it is faulty, you then should get a replacement.

Some basic advantages come with using a multimeter; these include:

  • It can display measurements reading value in either memory or synchronized with a PC.
  • It has resistance so it is not prone to mechanical damages.
  • It serves a variety of purposes. 
  • It is very accurate and its reading value does not necessarily depend on your battery charge.
  • In case your probes are not connected well it will still give you a correct value but with a negative sign or a minus signing being also displayed on the screen.
  • The measurements are accurate
  • Requires absolutely zero adjustment

As you can see a multimeter works quite effectively and has a variety of functions.


Based on the above information, you now have basic knowledge on the device known as the multimeter as well as how it works and the benefits it comes with. Therefore, it is evident that making use of this gadget is straightforward as it is not very complicated.

However, if you are experiencing any trouble using it, you can always refer to your manufacturer user manual to get more comprehensive guidance. Consequently, you will be in a position to best make use of the multimeter without having to hire a professional hence save your hard-earned money while still resolving whichever issues you are experiencing.

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