Last Updated on June 18, 2020
Do you need a voltmeter or a multimeter? You may already have some idea as to what the differences between these models are, but it never hurts to double-check that what you know is correct before you buy. Or, if you have no idea which kind will be right for you, then you should read on to find out if you need a voltmeter or a multimeter.
Volts are a unit of measure that represents the difference in potential between two nodes of an electric current. Consequently, voltmeters measure that difference and give the result in volts. Some voltmeter models are designed to work with alternating current, others with direct current, and the best models are capable of measuring both.
The heart of a voltmeter is a current-carrying fine-wire coil. This coil is suspended in an external magnetic field. You connect clamps or leads on the device to the power source that you want to measure, and then the current flows through the voltmeter. That current reacts with the magnetic field around the coil, which begins to spin in response.
The rotation causes a needle to move on an analog voltmeter, which you then read to know what the voltage is. Digital versions work slightly differently, and they more resistant to outside magnetic interference, and they don’t use a coil that is at risk of damage.
The one downside to a digital voltmeter is that it tends to update more slowly than an analog version, so fast changes in voltage are harder to identify.
The multimeter can record voltage, like a voltmeter, but it is also capable of measuring ohms and amperes, the units of resistance and current, respectively. High-end units can also measure other things like temperature, inductance, capacitance, frequency, relative humidity, and acidity, which gives them the flexibility to be used on all kinds of tasks.
They typically have a range between 200mV and 2000 volts, which means that you can use them on a variety of common circuits with a good degree of accuracy.
Analog multimeters are sometimes called “VOMs,” which is short for Voltage-Ohms-Amperes. Newer, digital models are often abbreviated “DMM” for, you guessed it, Digital Multimeter. Because the different measurements require different internal resistors to get accurate measurements, they sometimes have different external ports to which you must connect the test wires, so that you can get an accurate reading.
Multimeters can be very expensive. The price increases with the number of things that it can measure and the range of current and voltages with which it can work. Digital models tend to be more expensive than analog ones, and the best digital models can cost thousands of dollars, though you won’t need one that expensive for most household tasks.
The differences between these two tools are straightforward. If you only need to measure voltage, then you’re fine with just a voltmeter. If you want to measure voltage and other things like resistance and current, then you’re going to need a multimeter. The biggest difference in both tools is going to be whether you buy a digital or analog version. Digital voltmeters and multimeters tend to be more accurate, but also generally come with a larger price tag.
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Hi there! My name is Adam and I write for HealthyHandyman. I have a great passion for writing about everything related to tools, home improvement, and DIY. In my spare time, I'm either fishing, playing the guitar, or spending quality time with my beloved wife. You'll also often find me in my workshop working on some new project!