An Electrician’s Best Friend: The Best Multimeter in 2022

While multimeters are normally considered to be in the realm of electricians and electronic technicians, they’re useful to anyone who ever works with electricity. It doesn't matter if you're repairing a car, wiring a ceiling fan, or just checking the batteries in your flashlight, a multimeter will tell you what you need to know.

The name "multimeter" comes from the idea that one meter takes the place of several different ones, performing all of their functions at once; that's what makes these devices so useful for troubleshooting. If technicians didn't have multimeters to use, they'd have to carry around several different meters so that they could hook the right one up when they needed it.

The basic functions of a multimeter are:

- Measure AC and DC voltage
- Measure current in milliamps
- Measure resistance in ohms

To do this, most multimeters have a rotary selector switch which allows the user to set it to read exactly what they want. Some modern digital multimeters are automatic, eliminating the rotary switch or limiting the number of settings available.

Analog or Digital?

Originally, all multimeters were analog; in more recent times, analog multimeters have given way to digital display models. Even those have changed, with portable multimeters almost totally having taken over the market from the larger, digital bench multimeters. Today’s portables often have additional functions as well.

While digital multimeters are much more popular than analog ones, this doesn’t mean analog meters have become obsolete. There is one thing analog multimeters do much better than digital ones, and that is reacting to voltage and impedance fluctuations rapidly. This makes them valuable for some types of tests which can’t be easily accomplished with a digital display multimeter.

For example, when checking continuity, you have to wait several seconds for a digital multimeter to give you a reading. However, the same reading happens almost instantaneously with an analog meter. For that reason alone, there is a valid reason to have an analog multimeter even if you have a digital one.

Multimeters can vary extensively in price. Mostly what you are paying for with the more expensive ones are dependability and additional functions. The additions which I mentioned are available for digital multimeters, such as measuring temperature, generally only come with the higher cost ones. However, some low-cost digital multimeters are starting to add those features as well.

Some of the optional scales or ranges that you find on more expensive multimeters include:

What's Different Between a "Good" Multimeter and a Budget Multimeter?

Temperature

Some multimeters have a built-in temperature reading capability. This requires using a special temperature probe which usually comes with the meter. Additional types of probes are available for special needs.

RMS AC voltage

Since AC voltage is cyclical, the voltage measurement is actually the peak of the cycle. However, that can vary a bit. RMS stands for "root means square." It is merely a mathematical computation used for determining the actual AC voltage. This is considered to be a more accurate measurement of the actual AC voltage.

High amperage readings

Most multimeters only measure current in the milliamp range. A few offer a higher range, which measures up to 10 or 20 amps. This usually requires disconnecting the positive (red) lead and connecting it to a special jack. If the meter does not have this option and you try to connect it to one of these higher amp circuits, it will blow the fuse, at a minimum, in addition to the potential for more serious damage.

Capacitance

Capacitance is the measure of how much electricity a capacitor can hold. Some electronic circuits also have capacitance, even if they don't have capacitors installed.  Rather than utilize a separate instrument to measure the capacitance in a circuit, you can now check it with your multimeter if it has this option.

Frequency

Measurement of frequency requires the ability to count the number of pulses or waves happening per second, something quite different than other measurement functions. But the clock frequency that equipment is functioning at is important for troubleshooting many modern devices.

Duty cycle

Duty cycle refers to what percentage of the time a device is operating. This is fairly easy to tell with something like an air compressor, but extremely difficult for many smaller devices.

Auto-ranging

For any single type of measurement, establishing a range helps the meter to display the data correctly. Auto-ranging means the meter selects the range automatically and informs you on the screen of what range it has selected, thereby saving you time in setting up the meter for a particular measurement. This is especially useful when the reading is outside of the expected range as you don't have to keep changing the range yourself until the meter gives you the reading.

Graphing display

Graphs are something new in multimeters and only a few of the digital ones provide it. In doing so, they give you information about the reading to make it easier to understand how to apply that reading. While not useful for everything, graphing displays are extremely useful for a reading that is changing all the time.

Multimeter connectivity

The connection between the multimeter and the circuit to be tested is accomplished through a set of test leads, which are usually color-coded red (positive) and black (negative). The most common type of connection is a 1/8" diameter "banana plug" which is easy to connect and allows for quick change-out to a wide variety of other types of leads. Some compact multimeters use "pin plugs" rather than banana plugs, which are only about 1/32" in diameter.

The leads which come packaged with the meter may not be all that good, so you might want to buy some better ones. The major difference is the tips themselves, how sharp they are, and how far they extend out of the plastic handle. The longer they are, the easier it is to use them.

There are also leads available that come with clips to connect more permanently to the item you are measuring to facilitate measurement, especially in cases where it feels like you need three hands.

Multimeter cases

Multimeters are sensitive to shock, especially analog ones. Many manufacturers provide cases of rubber over-molding to protect their products from the inadvertent spills that happen in life. This is not an unnecessary extra, but rather insurance to help ensure a long life for your meter.