Multimeters Overview

What Are Multimeters?

A multimeter is a tool that can measure the properties of AC and DC voltage, current, and resistance. The multimeter will actually combine several different types of meter into a single device. This is more practical and more efficient for those who have to use the devices. They combine the properties of a voltmeter, as well as an ammeter and an ohmmeter. Two different sorts of multimeter are available – analog and digital. While they serve much the same function, they are different enough that each deserves its own section.

One of the things that buyers need to understand is that different multimeters have certain range specifications. It is important to make sure you are getting the right device for your needs.

It is also important to understand how all of the different elements of the device work, and what each of the meter types does. The three parts of the meter – voltmeter, ohmmeter, and ammeter – all have different functions.

The voltmeter is capable of measuring the amount of AC or DC voltage that is traveling and flowing through a circuit. The measurement of the voltage is actually a measurement in the difference in potential energy from two different points. The ammeter measures the amount of current that flows through a closed circuit. It does this by interrupting the circuit. An ohmmeter will find the amount of resistance in a circuit. It measures this in ohms.


How Does a Multimeter Work?

A multimeter has several different parts necessary for measuring the voltage, resistance, and current – the display, the selection knob, and the ports. The display is the readout area while the selector knob lets users choose what they want to read – ohms, milliamps, or volts. The ports allow the connection of probes to the meter. Those probes then attach to the various devices the user wants to measure with the meter.


What Are Analog Multimeters?

An analog multimeter, sometimes called an AMM, is capable of measuring the voltage, current, and resistance. They display on an analog meter makes use of a micro-ammeter, which moves a needle or pointer over the calibrated scale to give the user a reading. These are generally better for measuring smaller voltages and currents.


What Are Digital Multimeters?

Today, these are the most common type of multimeter. They have a digital display that is easy to read, and some of the digital models will even have a display that can light up. This is perfect for users who are using the meter in low light situations. One of the biggest reasons these are becoming so popular is that they tend to be far more accurate than the analog multimeters. Some of the things that people need to consider when buying their digital multimeters are the resistance, or impedance, as well as the range. The range setting is vital for accurate results. For example, testing a small voltage of a device, such as 12-volt on a range of 0 – 25 volts will provide an accurate result, whereas using a meter with a range up to 500 volts would not generally offer the same amount of accuracy.

The digital multimeters will fall into one of four different categories based on how they are to be used.


  • Category I – These are used whenever the equipment does not have a direct connection to the mains.
  • Category II – The meters in this category are used on the single-phase mains final sub-circuits.
  • Category III – Users choose this category for measuring permanently installed loads. These could include motors and three-phase appliance outlets.
  • Category IV – These are used when the fault current levels are extremely high, such as supply meters and main panels.


What Are Multimeters Used For?

These devices are extremely helpful for those who have to try to figure out electrical problems. They are useful for measuring circuits, wall outlets, and other electrical components. Engineers and individuals will use the meters to test batteries, switches, power sources, and motors as well. They are ideal for finding malfunctions, and they can help to narrow the cause of those malfunctions.

The most common uses for multimeters are actually to measure the voltage, current, and resistance. However, some types of meters may actually have different and specialized functions. They could include measuring capacitance in farads, decibels, conductance, frequency, inductance, and temperature.

In addition, it is possible to add certain types of sensors to some multimeters. These additional sensors can measure things such as the wind speed, relative humidity, light, and acidity and alkalinity. Of course, these are very specialized uses, and most who use the devices will not need them for those types of measurements.


Who Uses Multimeters?

Many different individuals may find a need to use a multimeter on occasion, or as a part of their job. Those who work in the electronics field, whether they are engineers or another electrical specialist, have a need to measure a variety of different devices. However, individuals and hobbyists who are building their own projects will find that the multimeter is a great addition to their toolbox. In can help to ensure their devices are working properly, and it can help them to locate any issues with the electronics they are fixing or building.


What Are Multimeter Accessories?

When buying a multimeter, you will find that they have a host of different accessories that go along with them as well. Just as you need to make sure you are putting enough thought into getting the right meter for the measurements you need to make, you also need to look at all of the various accessories and see which of those might be able to make using the meter easier. Some of the most common include clips that attach to the probes, allowing the meter to clamp onto a wider range of devices for measurements.


What Are Multimeter Application Adapters?

An application adapter can provide your multimeter with near limitless options. Each of these adapters has the power to give your meter a different function. Some of the most common types of adapters include those for temperature and pressure. Temperature adapters will let your meter to measure temperature, while pressure adapters allow you to measure pressure, naturally.

However, quite a few other options exist as well, including PC adapters, fiber optic meter adapters, thermocouple adapters, and stray voltage adapters. All of the different options help to give your multimeter a wider range of functions without you needing to buy additional tools aside from the adapters.


What Are Multimeter Cases and Holders?

While they are more rugged than many types of electronic devices are, owners still need to make sure they are taking good care of their multimeters. Keeping them in a proper case or holder is a good idea. Many different types of cases are available, including hard and soft cases. Many even have clips that can attach them to your belt so you can carry the meter with you. This makes it easier to keep with you while working. Engineers who have to use these meters throughout the day will likely find these cases helpful. Some of the cases are actually bags that have room for a variety of other tools in them. Having both could actually be helpful.

Because there are so many different types of cases available, whether you want a hard case, soft case, or bag, you should have no trouble finding what you need. You just need to be sure it will fit your particular model of multimeter before you buy.


What Are Multimeter Current Clamp Adapters?

Since the meters have certain ranges and types of measurements they can obtain, buyers would normally have to buy several different meters if they hoped to measure a wide range of different devices. This could become expensive, and it could be confusing to have so many meters. While having a few meters might be fine, it is generally a good idea to look into the current clamp adapters that are available as well. These adapters will change the range for measurements, and they will fit right onto your own meter. This way, you can choose to buy several adapters rather than buying new meters. It is a smart and cost effective option. Again, since there are so many different types of meters out there, it is very important to make sure that you are getting the right adapter for the meter you own.


What Are Multimeter Fuses?

Since multimeters have voltage and current running through them every time they’re used to test devices, batteries, and other items, there is always a change that you could bring too much power into the device by mistake. This often happens with those who are just getting started with the devices. Fortunately, the multimeter has fuses that will blow in the event this happens. This ensures that the meter is safe and undamaged, and that the only thing you will need to replace is the fuse.

To replace the fuse, you will need to take the multimeter apart and then pop out the fuse by lifting it gently out of the holder. When buying and replacing the fuse, you need to replace it with the correct fuse. Always replace the fuse with the exact same type of fuse. One of the mistakes that you must not make is replacing the fuse with a larger fuse thinking that it will change the range of the multimeter for you. It will just end up breaking the multimeter.

Even though fuses in these devices do not blow often, it might be a good idea to have a few of them on hand, just in case.


What Are Multimeter Kits?

One of the very best ways to get a multimeter, as well as a case and all of the parts you need, is to buy a multimeter kit. The kits come in a wide range of styles with different meters, different tools and accessories, and different cases. Naturally, they will range in price as well. For those who are just starting to look for a multimeter, the kits are the best and most affordable option. One of the other benefits of buying everything in a kit is that you can be sure all of it actually goes together and will work seamlessly together. There is no worry that you might be buying some of the wrong parts.


What Are Multimeter Rack Mount Kits?

In some cases, such as industrial settings, where a large amount of testing with different meters happens on a regular basis, it might actually be an easier option to mount several multimeters together. It is possible to mount several of the same type together, or to have a mount that contains different types of meters. For those that have different meters, it is important to make sure each of the meters is labeled or marked in some fashion.


What Is Multimeter Software?

The information gathered by the multimeter needs to go somewhere. You need to collect the data and log it into a computer, and without the right software, it is impossible. Some meters actually come with data logging software that you can use to record and measure information. Several types of software are available today. Users should look at the different software options and see which one seems to fit their needs the best. Some of the multimeter kits will actually come with the software for you to use.


What Are Multimeter Test Leads?

The test leads come off the probes that connect to the multimeter. These leads are available in a variety of different styles and options so they can fit onto many different sorts of machines that need testing. Some of the most common connector types include crocodile clips, right angle plugs, straight plugs, and spring hooks. Users should make sure they have a variety of different types of devices in order to test as many different types of devices as possible. Having a good selection of test leads is relatively cheap, and it ensures you never have to purchase new leads at the last minute.