If you’re doing any kind of electrical work—no matter what the application is—one of the best tools you can have at your disposal is a multimeter. If you’re just getting started, here’s how to use one and what all those confusing symbols mean.
In this guide, I’ll be referring to my own multimeter and using that as our example throughout this guide.
Yours might be slightly different in some ways, but all multimeters are similar for the most part.| Misumi USA | |
| |
| Get Fast Shipping & Better Pricing. Misumi. Empowering Engineers! | |
| us.misumi-ec.com | |
| Learn more |
Which Multimeter Should You Get?
There’s really not one single multimeter that you should shoot for, and it really depends on what features you want (or even features that you don’t need).
You can get something basic like this $8 model, which comes with everything you would need. Or you can spend a bit more cash and get something fancier, like this one from AstroAI. It comes with an auto-ranging feature, which means you don’t have to select a specific number value and worry about it being too high or low. It can also measure frequency and even temperature.
What Do All the Symbols Mean?
There’s a lot going on when you look at the selection knob on a multimeter, but if you’re only going to be doing some basic stuff, you won’t even use half of all the settings. In any case, here’s a rundown of what each symbol means on my multimeter:
- Direct Current Voltage (DCV): Sometimes it will be denoted with a V– instead. This setting is used to measure direct current (DC) voltage in things like batteries.
- Alternating Current Voltage (ACV): Sometimes it will be denoted with a V~ instead. This setting is used to measure the voltage from alternating current sources, which is pretty much anything that plugs into an outlet, as well as the power coming from the outlet itself.
- Resistance (Ω): This measures how much resistance there is in the circuit. The lower the number, the easier it is for the current to flow through, and vice versa.
- Continuity: Usually denoted by a wave or diode symbol. This simply tests whether or not a circuit is complete by sending a very small amount of current through the circuit and seeing if it makes it out the other end. If not, then there’s something along the circuit that’s causing a problem—find it!
- Direct Current Amperage (DCA): Similar to DCV, but instead of giving you a voltage reading, it will tell you the amperage.
- Direct Current Gain (hFE): This setting is to test transistors and their DC gain, but it’s mostly useless, since most electricians and hobbyists will use the continuity check instead.
Your multimeter might also have a dedicated setting for testing the amperage of AA, AAA, and 9V batteries. This setting is usually denoted with the battery symbol.
Again, you probably won’t even use half of the settings shown, so don’t get overwhelmed if you only know what a few of them do.
How to Use a Multimeter
For starters, lets go over some of the different parts of a multimeter. At the very basic level you have the device itself, along with two probes, which are the black and red cables that have plugs on one end and metal tips on the other.
The multimeter itself has a display at the top, which gives you your readout, and there’s a big selection knob that you can spin around to select a specific setting. Each setting may also have different number values, which are there to measure different strengths of voltages, resistances, and amps. So if you have your multimeter set to 20 in the DCV section, the multimeter will measure voltages up to 20 volts.
Your multimeter will also have two or three ports for plugging in the probes (pictured above):
- The COM port stands for “Common”, and the black probe will always plug into this port.
- The VΩmA port (sometimes denoted as mAVΩ) is simply an acronym for voltage, resistance, and current (in milliamps). This is where the red probe will plug into if you’re measuring voltage,…
The post How to Use a Multimeter appeared first on FeedBox.