A measurement device that can assess several electrical characteristics is a multimeter. The term “volt-ohm-milliammeter” (VOM) refers to a multimeter that has the ability to measure voltage, resistance, and current. This is because the device has a voltmeter, ammeter, and ohmmeter functions. Some include the measuring of other characteristics like capacitance and temperature.
The size, features, and cost of multimeters vary. They may be highly accurate bench instruments or portable handheld devices. Multimeters can be purchased for as little as $10, while laboratory-grade ones with verified calibration can cost as much as $5,000.
Readings are displayed on an analog multimeter’s microammeter, which has a moving pointer. Because they are more affordable, accurate, and physically robust than analog multimeters, digital multimeters (DMM, DVOM) with numeric displays have all but replaced analog multimeters.
Well, in this article, we’ll be discussing multimeters as the answers to the following questions will be answered:
- What are multimeters?
- What are multimeters used for and their functions?
- How to use a multimeter?
- What are the classifications and types of multimeters?
- What is the difference between analog and digital multimeters?
- What are the benefits and limitations of a digital multimeter?
Let’s begin!
Contents
What are multimeters?
An electronic device called a multimeter is used to test circuit resistance, amps, and voltage. Professionals can use multimeters to check voltage, resistance, and electrical current levels by connecting two leads to various electrical system components. This device is also sometimes referred to as a volt-ohm meter or volt-ohm-milliampere (VOM).
In the field of information technology, multimeters are quite useful. Professionals may use a multimeter during hardware troubleshooting to determine whether certain hardware devices are receiving enough current or whether anything has changed in an existing IT configuration. The multimeter, which is often associated with home or commercial electricians, can also be used by IT specialists to identify problems with the energy supplies that power sophisticated data systems.
Modern digital multimeters are capable of measuring incredibly minute variations or fluctuations. Although some multimeters test wider voltage ranges, experts point out that it will be harder to spot tiny changes in these higher ranges. The analog multimeters use a microammeter with a moving pointer to display readings.
What are multimeters used for and their functions?
Applications for different multimeter types include several electrical and electronic projects for component testing as well as used in a variety of measuring applications. A digital multimeter is a test instrument used to measure two or more electrical values, primarily resistance, current, and voltage (in volts and amps) (ohms). For technicians working in the electrical and electronic industries, it is a typical diagnostic tool.
Multimeters can be used in different applications for the following purpose:
- Temperature and Environmental Applications – Low-cost weather station and DMM internal temperature
- Voltage Measurements – High and low-value DC measurement and Peak to Peak and DC average measurement.
- Current Measurements – DC measurement and true RMS AC.
- Resistance Measurement – Micro ohmmeter, measuring resistance with constant voltage and measuring resistance with a constant current.
- Time and Frequency measurement – Fast frequency and time measurement.
Depending on the model, a multimeter can read a wide range of values. Basic testers can be used to check continuity, a quick test to confirm a full circuit, and they measure voltage, amperage, and resistance. Advanced multimeters can check for AC (alternating current) voltage and amperage, DC (direct current) voltage and amperage, resistance (ohms), Capacity (farads), Conductance (siemens), Decibels, Duty cycle, Frequency (Hz), Inductance (henrys), and temperature Celsius or Fahrenheit.
Accessories or special sensors can be attached to some multimeters for additional readings like light level, acidity, alkalinity, wind speed, and relative humidity.
How to use a multimeter?
A multimeter’s face normally consists of four parts: a display, buttons, a dial, and input jacks. Measurement readouts can be seen on the display, and different functions can be selected via the buttons; the options depend on the model. Rotary switch or dial for choosing the initial measurement values (volts, amps, ohms). and the test leads are plugged into the input connectors.
The testing capabilities of single-task meters, such as the voltmeter (for measuring volts), ammeter (for measuring amps), and ohmmeter, are combined in digital multimeters (ohms). They frequently come with a number of extra specialized features or cutting-edge alternatives. Therefore, technicians with certain requirements might look for a model that is tailored to their requirements.
Watch the video below to learn how to use a multimeter:
What are the classifications and types of multimeters?
Multimeters are classified into two such as analog and digital types.
Analog multimeter
A moving coil meter is used in the construction of the analog multimeter, also known as the VOM (Volt-Ohm-Milliammeter), together with a pointer to show the reading on the scale. A coil that is looped around a drum and positioned between two permanent magnets makes up the moving coil meter.
The magnetic field of the permanent magnets reacts with the magnetic field of the coil when current flows through it, creating a force that causes the pointer linked to the drum to deflect on the scale, giving the current reading. In order to manage the deflection of the pointer, it additionally comprises springs attached to the drum, which exert an opposing force on the drum’s motion.
The D Arsonval movement mentioned above can be utilized directly to measure DC. The current to be measured should, however, be less than the meter’s full-scale deflection current. The current divider rule is employed for higher currents. The meter can also be used to measure current in many ranges by using various quantities of shunt resistors. The device must be linked in series with the unidentified current source in order to measure current.
Digital Multimeter
A digital multimeter is what we utilized most frequently (DMM). The DMM can carry out all tasks from AC to DC aside from analog. The figure shows two probes with positive and negative indications in black and red. In order to test ohms, volts, or amperes, the user attached the red probe and the black probe to the COM JACK.
Voltage, resistance, and diode testing may all be done using the COM and VΩ jacks on the right side of the image. When an LCD displays the measurement under consideration, the two connectors are used (volts, ohms, amps, etc.). The overload protection shields the user and guards against damage to the circuit and meter.
The internal circuitry of the digital multimeter comprises a signal conditioning circuitry, an analog to digital-converter, an LCD, a knob to select different ranges of the three electrical characteristics, and other components. Depending on where the knob is positioned, concentric rings on the PCB are either connected or detached. The part of the PCB is triggered to carry out the corresponding measurement as soon as the required parameter and the range are chosen.
The common types of multimeters include
- Fluke multimeter
- Clamp digital multimeter
- Autoranging multimeter
What is the difference between analog and digital multimeters?
The table below explains the difference between analog and digital multimeters:
| Analog Multimeter | Digital Multimeter |
| Restrictive electrical quantities including resistance, voltage, and current are measured with an analog multimeter.
| With a digital multimeter, you can calculate a variety of electrical values, including voltage, current, capacitance, resistance, diode, and impedance values, among others. |
| Analog multimeter is larger in size | A Digital multimeter is smaller |
| This meter provides the reading on a scale next to the pointer. | This meter provides the reading in the form of numeric on an LCD. |
| The Analog multimeter is calibrated manually. | Digital multimeters are calibrated automatically. |
| Their construction is simple | Their construction is complicated because of the involvement of components like electronics and logic. |
| Analog multimeters are less accurate because of the parallax errors & readings of the wrong pointer | Digital multimeters are very accurate |
| It doesn’t need ADC to show reading. | It needs ADC to exhibit the reading. |
| Input resistance is not stable | Input resistance is stable |
| The pointer of this multimeter tries to turn aside to the left in reverse polarity. | This multimeter shows a negative quantity once the polarity is reversed. |
| These are less cost | These are expensive |
Read more: Understanding the car”s Air conditioning condenser fan
Multimeter FAQs
What is a multimeter explain?
A volt/ohm meter commonly referred to as a multimeter or multitester is an electronic measuring device that integrates multiple measurement capabilities into a single unit. A standard multimeter might have the capability to measure voltage, current, and resistance, among other things.
What are the 4 functions of a multimeter?
Simple budget models include a limited range of features that are adequate for completing routine, everyday chores like checking the conductors, ensuring circuit continuity, measuring the voltage in a socket, or checking a car’s battery level. Depending on the instrument’s intended use, the multimeter has a variety of additional features.
What are multimeter and their types?
A tester used to measure electrical voltage, current, resistance, and other quantities is a multimeter, also referred to as an avometer. The two basic types of multimeters are analog and digital. Both are utilized in electrical circuits for measuring and fault detection.
Why is called a multimeter?
A single measuring device is said to be a multimeter if it can measure many quantities at once, such as voltage, current, and resistance. Since it can measure several electrical variables simultaneously, it is known as a multimeter.
Why is a multimeter important?
The voltmeter, or more frequently the multimeter, is a fantastic tool that can diagnose almost every electrical system and malfunction that exists. No of how frequently you use them or what function they serve, understanding how they operate will always allow you to accomplish more.
What is the advantage of a multimeter?
External devices can interface with the output. There are smaller sizes available. It can be used to measure both the quantity of AC and DC. It can be used to measure a variety of factors, including resistance, voltage, and current, among others.
What are the three types of multimeters?
- Fluke multimeter
- Autoranging multimeter
- Clamp multimeter
What are the four types of multimeters?
There are four different classifications for multimeters: CAT I, CAT II, CAT III, and CAT IV. The use of the proper category is crucial depending on the circuit being evaluated. Voltage, current, and resistance may all be measured with a standard digital multimeter.
Why multimeter is important in electrical work?
One of the most crucial tools in an electrician’s toolbox is digital multimeters (DMMs). They provide a wide range of functions and make it quick and easy to figure out what’s happening with your electrical system. But more significantly, they provide a trustworthy way to identify the lack of voltage.
What are the limitations of a multimeter?
Disadvantages of digital multimeter:
- It is more expensive than the analog type.
- The LCD display depends on a battery or an applying external power source.
- There is a voltage limitation.
- It should be used as per manufacturer range and as per category rating.
- In case of fluctuations or transients, it can record an error.
Conclusion
Multimeters are great electrical devices that are used to measure electrical currents. Professionals can use multimeters to check voltage, resistance, and electrical current levels by connecting two leads to various electrical system components. This device is also sometimes referred to as a volt-ohm meter or volt-ohm-milliampere (VOM).
That is all for this article, where the answers to the following questions are been discussed:
- What are multimeters?
- What are multimeters used for and their functions?
- How to use a multimeter?
- What are the classifications and types of multimeters?
- What is the difference between analog and digital multimeters?
- What are the benefits and limitations of digital multimeters?
Related Article:
- How to test a car battery with a multimeter
- Lists of best Multimeter for automotive
- Symptoms of a faulty map sensor
- Symptoms of a fouled spark plug
- Understanding Canister Purge Valve
I hope you learned a lot from the reading, if so, kindly share with others. Thanks for reading, see you around!
