Multimeters, more correctly known as volt-ohm meters, are the electricians and electronic tech’s standard troubleshooting tool. With it, they can check a wide range of electronic devices, measuring voltage, current, and resistance in circuits. Those measurements are essential for effective troubleshooting of electronic and electrical circuits.
These instruments have been around for years, ever since society started using electricity to power our lives. The multimeter eliminates the need for the technician to have multiple meters to work with, making their toolbox lighter and their work easier.
While all multimeters perform many of the same functions, there are some specialty functions that are only performed by some specific models which separates higher end options from more basic models. For more information about what to look for in a multimeter, check out our buyer's guide listed below.
Best Digital Multimeter:
Multimeters are called by that name because they perform the function of multiple meters. A typical multimeter can be used to measure AC or DC voltage, impedance and current. Some add other functions, such as measuring temperature, capacitance and frequency. So, you can see that if one doesn't have a multimeter, they would need a number of different meters to accomplish the same task.
These are the electrician and electronic technician’s best friend and most used piece of test equipment. While there are many other types of test equipment used for testing, calibrating and repairing electronic equipment, none of them can accomplish what a multimeter can in the hands of a skilled technician.
Multimeters used to be analog, providing a reading by a needle moving across a complex scale. You can still find some models of these multimeters around. However, the digital multimeter has largely taken over the market, as they are more accurate, easier to read, and more compact. Today’s digital multimeters are almost exclusively portable units.
Since they use a LDC display, multimeters should be protected from high heat. Leaving them in a hot garage or hot vehicle all the time will eventually ruin the display, necessitating an expensive repair or replacement of the unit. With normal use and with protecting the unit from excessive heat, a multimeter should last for years of satisfactory use.
Most multimeters have a rotary switch for selecting the type of input that is to be measured. In some cases, the meter is auto-ranging which means that it selects the correct value range to match the application. In other cases, the various ranges are selected with the same rotary switch used for selecting the input type.
They might also have multiple input jacks, rather than just the positive and negative ones. These additional inputs are for measuring amperages above 1 amp or some of the other types of inputs that might be built into a multimeter.
While these units can be calibrated, they usually don’t need to be. The electronic circuitry in a multimeter is stable enough to last for years without re-calibration. The only time regular calibration is normally required is when the multimeter is used for the calibration of delicate scientific or medical equipment. In those cases, even a 0.1 percent deviation is unacceptable.
When picking a multimeter, be sure that it will cover the types of inputs that you need to measure. This means both the range and the type of signal. Selecting a meter with extra capabilities does not usually detract from the quality or accuracy of the meter, merely provides additional functions that it can do.
These tools typically ship with a pair of leads, one red and the other black, which are used for connecting them to the equipment that needs to be measured. The leads are changeable, almost universally being connected to the meter with banana plugs. Some of the aftermarket leads that are available provide advantages in certain circumstances, such as working with integrated circuits and being able to clip the leads to the test points and operate hands free.
Fluke is the biggest manufacturer of digital multimeters around. This unit provides incredible accuracy, as well as both auto-ranging and manual-ranging capability. Read Full Review
This multimeter is designed specifically for the commercial electrician, offering features that they need. A true RMS meter, it also has a voltage detection circuit, to help quickly determine which circuits are live. Read Full Review
This unit by Fieldpiece works with their series of accessory heads, to make a wide variety of measurements. It comes with the clamp on probe for measuring current flowing through a line. Read Full Review
Like the Fluke, this unit has a bar graph on the display for quick reading of unstable voltages. It can also measure capacitance, frequency, duty cycle and temperature. Read Full Review
Best Analog Multimeter:
Before digital, there was analog; specifically, before digital multimeters there were analog multimeters. They performed essentially the same functions that a digital multimeter did, but had an analog meter, instead of a digital readout. For those who don’t know what an analog meter is, that’s the type with a needle that swings across a scale that’s printed on the face of the meter. You still find them in common use today, although not for multimeters. Most car’s fuel gauges, temperature gauges (if they have one), and oil pressure gauges (if they have one) are analog meters. You generally only find digital dashboards on high dollar luxury or high performance cars.
An analog multimeter has a number of scales printed on it, to accommodate the different types of inputs that the meter is capable of measuring. Typically, these are grouped and color-coded. The grouping is of the different ranges that can be read for the same type of input. For example there might be four different AC voltage ranges grouped together and printed on the meter face in red. Impedance might be three different black ranges. The same needle is used with all of the input types, but the proper scale must be read.
Due to the analog scale, it’s much harder to read an analog multimeter than a digital one. To help with accuracy, better analog multimeters have a mirror strip along the meter face. This allows you to verify that you are looking at the needle straight on, so that you can get the most accurate reading. If the reflection of the needle is not visible, you are looking straight on at the meter. Better meters will be larger, making it easier to read the scales accurately.
Because of the way that they function, analog multimeters can’t be auto ranging, but only manual ranging. It’s also much harder to add some of the additional functions that you find on digital multimeters. You won’t find analog models which measure temperature, frequency, or capacitance.
Analog multimeters do have one major advantage over digital ones, which probably explains why they are still manufactured. That is, analog multimeters react instantly, whereas digital ones always have a delay. While the delay doesn’t cause a problem for many things, there are some times, like checking continuity of a number of wires in a snake, where that delay adds a lot of time to the overall process. Instant reading is also necessary for seeing transient voltages.
Because these are analog meters, they need to be zeroed before use. There is always a dial for zeroing the meter. Some bigger one have two dials, one for zeroing and the other used for full-scale zero of impedance. In those cases, first the zero is set, then the leads are shorted together, so that the full-scale setting can be zeroed.
You can find analog multimeters that are even less expensive than the budget digital ones. In this list, I’ve shown an assortment, starting with the best meters on the market and ending with a couple of really good low-dollar ones.
Simpson provides the best of the best in analog multimeters. This model has built-in overload protection, and a much wider readable range than most multimeters do. Read Full Review
In addition to the normal function, this meter has a decibel function for use in audio engineering. The meter is well-designed to work with, including making the window of glass, to make it more chemical resistant. Read Full Review
Getting down to something a little more affordable, we find this analog meter from Hioki. It is drop proof from a height of one meter to prevent shock damage. It also works with additional probes for temperature and battery checking. Read Full Review
For those that are looking for a low-cost analog multimeter, this unit from Mastech is a good choice. It is designed to work with a belt holster, making it easy to take with you. Read Full Review
Best Budget Digital Multimeter:
Although a multimeter is an essential piece of test equipment for electricians and electronic techs, not everyone needs one all the time. For those who need one only once in a while, spending a couple hundred bucks on a high-quality multimeter may not make much sense. For those people, there are the budget multimeters.
Just because a multimeter is considered a budget unit, that doesnt mean that its not worth having. Actually, many budget multimeters perform as well, with as accurate a readings as the high dollar ones do. Often, the major difference is in the loss of some functions that the more expensive meters may include. So, the key to picking out a budget multimeter is to know what functions you really need, and to make sure that the multimeter you pick has those functions.
The minimum functions that you can expect to find in any multimeter are AC and DC voltage reading, impedance reading (ohms ?) and milliamp readings. Some may also have a higher ranging amp reading, up to 10 amps, but a budget meter may not.
In addition to those basic readings, higher dollar multimeters may add things like temperature, capacitance, inductance and frequency readings. If youre looking at a budget multimeter you probably dont need those things and you really cant expect to find them. Another thing you probably wont find is true RMS AC readings. This is a means of average AC electrical readings, which provides a more accurate reading. The only time this would be an issue is if you need very accurate AC voltage level readings, which most people dont need.
Digital multimeters can be either auto ranging or manual ranging. What that means is that the range for any particular reading is set automatically by the multimeter or manually by the user. Most of these low cost multimeters are manual ranging, as this saves the manufacturer the cost of the auto ranging circuitry.
Another place where manufacturers save money on budget multimeters is in the test leads. Generally speaking, you arent going to get a really good pair of test leads with a budget meter. What you receive will be functional, but nothing fancy. Should you need better test leads, you can buy them separately, replacing the original ones. This is much less expensive than buying an expensive multimeter just to get good test leads.
If the multimeter you buy has an off setting on the rotary switch, be sure to use it. While the current draw on an inactive multimeter isnt very high, they still draw some current. That means that they will eventually run down the batteries, usually right before you need to use it.
This "budget" multimeter has everything you'd expect to find on the high dollar ones. You can select whether to run in auto or manual ranging mode, for a wide variety of measurement tasks. Read Full Review
In addition to the typical multimeter functions, this meter from Amprobe has the capability of doing no-contact voltage checks. This allows you to find out whether circuits are hot, without having to connect the meter, a great time savings. Read Full Review
This meter is unique in that it offers connectivity to your computer for data upload and recording. It also has functions for measuring capacitance, frequency and temperature. Read Full Review
If you need to be able to take your mulitmeter with you, there's nothing like having a "mini" meter you can slip in your pocket. In addition to the standard functions, this one offers temperature reading and diode testing. Read Full Review
Multimeter Buyer's Guide
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; 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
In order 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, the analog multimeters have given way to digital 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’s react to voltage and impedance fluctuations rapidly. That makes them valuable for some types of tests which can’t be easily accomplished with a digital 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 valid reason to have an analog multimeter even if you have a digital one.
What's Different Between a "Good" Multimeter and a Budget Multimeter?
Multimeters can vary extensively in price. Mostly what you are paying for with the more expensive ones is 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 multimeter include:
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 additional to potential for more serious damage.
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.
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 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.
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.
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.
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 which 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.
Multimeters are sensitive to shock, especially analog ones. Many manufacturers provide cases or rubber overmolding 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.