You probably know a thing or two about multimeters if you are; a mechanical enthusiast or into electrical DIY projects. Many electrical engineers already know the value of multimeters and own one. Multimeters effectively detect electrical faults, thereby saving time during troubleshooting and, therefore, also saving you money.
But before we dwell any further, let us clarify a few basic terms that may appear in this article.
- Accuracy– this explains how close a measurement is to the actual value. For example, if the voltage of a battery is 9 volts, and the actual meter reading is 9 volts, it is an accurate reading. On the other hand, if the voltage is 9.12 volts, and the actual reading is 9 volts, it will still be accurate; however, it will not have many precision details.
- Precision– this is basically the decimals displayed to show the actual value. An example of a precise meter reading is 8.9875. This reading is precise but not accurate. Most of the time, a sound meter may have many decimals of precision and calibrated accuracy.
But what is a multimeter?
A multimeter is an electronic tool used to measure voltage, current, and resistance through voltage’s essential electronic attributes. Other than that, a multimeter can be used to test the flow between two points in an electrical circuit.
A multimeter has numerous functions. It can act as a voltmeter, ammeter, and also as an ohmmeter. This handheld instrument contains a positive and negative indicator and a numeric display. Therefore, it can be used to test batteries, wiring, power supplies, and electric motors since there is a variety of multimeters in the market. You need to know the right one you need to get the job done.
What are the different types of multimeters?
There are two types of multimeters; analog and digital multimeters. Without further ado, let us expound in detail.
- Analogue Multimeters
The analog multimeter is also known as the Volt-Ohm-Multimeter (VOM). This multimeter is built using a moving coil meter and a needle indicator that shows the reading on the scale. The moving meter has a coil wound around the drum, which is positioned between two permanent magnets. When the current passes through the coil, the magnetic field is generated in the ring. It thereby reacts to the permanent magnets forcing the needle indicator attached to the drum to avert on the scale, therefore showing the reading.
The analog multimeter is also made up of springs that are attached to the drum. They provide the opposing force to the drum’s movement to enable control deflection of the needle indicator.
Analog multimeters were the first sort to be manufactured. Although they are cheaper, they can be challenging to read. With that said, when buying an analog multimeter, make sure that it has a high sensitivity. A low sensitivity multimeter may distress the circuit, causing an inaccurate reading. Also, make sure that you select it has the right features.
- Digital Multimeter
The digital multimeter (DMM) is the most used type of multimeter today. The DMM is functional as it can perform all functions from AC to DC. This is something that the analog multimeter is not capable of. The digital multimeter has a negative and positive probe. A black and red color usually indicates them.
The DMM comprises an LCD screen for display and a knob to select the three different electrical attributes. It also consists of an internal circuit that features the signal conditioning and the analog and the digital converter.
A digital multimeter uses digital circuits; therefore, it’s safe to say that it measures the currents in discrete increments. It is worthwhile to note that the analog multimeter measures in a continuous range. Digital measurements are usually done in analog form. With that in mind, there is a conversion from analog to digital before the actual measurement takes place.
During the conversion, there is a slight delay. If the values are continually changing, then the reading may be affected. But this is not to say that the digital multimeters are not accurate. They fair better than their analog counterparts. A digital Multimeter is very accurate and will suit your needs perfectly.
Digital Multimeters have three categories; auto-ranging, clamp, and fluke multimeter.
- Auto-ranging Digital Multimeter– of all the digital multimeters, this is probably the easiest to operate. However, it is the most expensive. Since the central knob has fewer positions, it does not need to switch to what is being measured.
- Clamp Digital Multimeter– the principal function of a clamp multimeter is for measuring the electricity flow. It features a clamp feature that measures the amps, and the probes on hand measure the volts. The power consumption (watts) is generally calibrated by multiplying the voltage readings by the amps. Additionally, the clamp multimeter has different settings; hence, you have to select the desired setting when using it.
- Fluke Digital Multimeter– this digital multimeter is built with different collaborative tasks. It features a big display screen. This category of the digital multimeter is used to measure the electrical resistance and the voltage.
In some cases, some multimeters have advanced features that can measure frequency, duty circle, humidity, temperature, and pressure.
Fluke Digital Multimeters are the most common in the market today.
If you are an electrical technician, you understand what it means to have the right tools. Therefore, understanding the value of a multimeter is very crucial. The next important factor is understanding the different types of multimeters and the distinctive situation where each one will prove to be useful.
With that in mind, when choosing a multimeter, select one with the right features to suit your needs.