Have you ever held a digital multimeter, faced its intricate features and warnings, and been unsure of where to begin? Don’t worry; this article will lead you into the realm of digital multimeters and explain how to use them as well as the meanings of the numerous symbols.
As the name suggests, a digital multimeter is a versatile measurement tool that can measure a variety of variables, including voltage, current, resistance, and more. With a role in almost all electronic and electrical applications, it is a vital tool for electronic engineers and amateurs.
After that, we’ll use the ZOYI ZT219 as an illustration to discuss how to use digital multimeters and common symbols.
Let’s start by learning how to operate a digital multimeter. When you first receive the multimeter, you’ll notice three key parts: a display screen where readings are displayed; buttons or rotary for adjusting the measurement properties or units as needed; and input ports for attaching test leads.
Let’s now dissect and briefly explain some of the multimeter’s most significant symbols:
1. “V-” and “V~”: These two symbols represent direct current (DC) voltage and alternating current (AC) voltage, respectively. When measuring voltage, you need to determine whether your power source is DC or AC, then choose the corresponding position.
2. “A-” and “A~”: Like voltage, these symbols represent direct current (DC) and alternating current (AC), respectively. When measuring current, remember to insert the probe into the correct socket and open the circuit, because current flows through the circuit.
3. “Ω”: This symbol represents resistance. When measuring resistance, you need to disconnect the circuit, as resistance impedes current.
4. “Hz”: This symbol represents frequency, used for measuring the frequency of electric signals.
5. “diode”: This symbol represents diode testing. This is a very practical function that can be used to check whether diodes, transistors, and LEDs, etc., are working properly.
We then go into greater detail on the use and application of the various buttons on the digital multimeter:
1. HOLD button: If you press the “HOLD” button for about 2 seconds, the reading will not disappear. This feature is very useful when you are using the test probe to take readings and cannot see the multimeter.
2. REL button. It will zero out your most recent measurement. This button is very useful when measuring voltage differences. For example, when you are measuring the voltage difference of a distribution panel. First, read the measurement on one panel, press the “REL” button. Then read the voltage on another electrical panel. The result we get will be the voltage difference between the two panels.
3. MAX/MIN button. When we press this button, it will save the maximum and minimum values of the measurement. If the current or measured variable exceeds the defined range, the multimeter will sound an alarm. Note: this button is not applicable for measuring capacitance, frequency/duty cycle, or temperature.
4. SELECT button. This can switch the mode of the knob, simply put, it determines the function among the multiple options selected by the knob, only effective for voltage testing, current testing, and live testing.
5. NCV button: Move the knob to the “NCV” displayed on the screen. Place the multimeter around the object you are testing. If there is a faint alarm sound, it means there is a weak voltage; if there is a strong alarm sound, it means there is a strong voltage.
6. RANGE button. The digital multimeter has different ranges. Choose the range according to the measured variable. The range can be small or large, depending on what we are measuring. We can use the RANGE button to switch between auto range or manual range. If we know our measurement range very well, we can switch to manual range to improve our measurement speed.
Before measuring, you need to adjust the multimeter to the position corresponding to the parameter you want to measure. For example, if you want to measure DC voltage, turn the knob to the position marked “V-“. Then, insert the black common probe into the COM socket, and the red measurement probe into the VΩmA socket (or 10A socket, depending on the size of the current). In this way, you can use the probe to measure your circuit or device.
While the use of a digital multimeter might seem complex at first glance, once you get familiar with its basic operations and symbols, you’ll find that it’s a very intuitive and easy-to-use tool. It can help you with a variety of electrical measurements and fault diagnoses and is an essential tool for every electrical and electronics engineer. If you don’t yet have your own digital multimeter, go buy one now! You’ll find that it opens endless possibilities for your electronics projects.
The above is the basic usage of the digital multimeter and an explanation of the main symbols. We hope this article can help you better understand and use the digital multimeter, making your electronics projects go more smoothly. Remember, safety comes first, especially when dealing with electrical equipment. Ensure you know what you’re doing and understand the characteristics of the circuit or device you’re measuring.
