How to Measure DC Voltage with a Multimeter (Beginner's Guide)
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Voltage is perhaps the simplest and most commonly read multimeter measurement. While reading DC voltage may seem easy at first glance, getting good readings requires a deep knowledge of this single function.
In short, you can measure DC voltage with a multimeter by following these steps. First, switch the dial to DC voltage. Then place the black lead into the COM jack and the red leads into the V Ω jack. Then remove the red dipstick first and then the black dipstick. Then connect the test leads to the circuit. You can now read the voltage measurement on the display.
If you're a beginner and want to learn how to measure DC voltage with a multimeter—both digital and analog multimeters—you've come to the right place. We will teach you the whole process, including the analysis of the results.
What is constant voltage?
For understanding, DC voltage is a short form of the term "DC voltage" - a voltage capable of producing direct current. On the other hand, alternating voltage is capable of producing alternating current.
In general, DC is used to define systems with constant polarity. However, in this context, DC is mainly used to refer to quantities whose polarity does not change regularly, or quantities with zero frequency. Quantities that regularly change polarity with a positive frequency are called alternating current.
The voltage potential difference/unit charge between two positions in an electric field is the voltage. The movement and presence of charged particles (electrons) produce electrical energy. (1)
A potential difference occurs when electrons move between two points - from a point of low potential to a point of high potential. AC and DC are two types of electrical energy. (2)
The voltage derived from DC is what we are discussing here - DC voltage.
Examples of DC sources include batteries, solar panels, thermocouples, DC generators, and DC power converters to rectify AC.
How to measure DC voltage with a multimeter (digital)
- Switch the dial to DC voltage. If your DMM comes with millivolts DC and you don't know which one to choose, start with DC voltage as it is rated for higher voltage.
- Then insert the black probe into the COM connector.
- The red test leads must go inside the V Ω jack. Having done this, first remove the red dipstick and then the black dipstick.
- The fourth step is to connect test probes to the circuit (black probes to the negative polarity test point and red probes to the positive polarity test point).
Note. You should be aware that most modern multimeters can automatically detect polarity. When using digital multimeters, the red wire should not touch the positive terminal, and the black wire should not touch the negative terminal. If the probes touch opposite terminals, a negative symbol will appear on the display.
When using an analog multimeter, you must ensure that the leads are touching the correct terminals so as not to damage the multimeter.
- You can now read the voltage measurement on the display.
Helpful Tips for Measuring DC Voltage with a DMM
- Modern DMMs usually have an auto range by default, depending on the function displayed on the dial. You can change the range by pressing the "Range" button several times until you reach the desired range. The voltage measurement may fall into the low millivolt DC setting range. Don't worry. Remove the test probes, switch the dial to read millivolts DC, reinsert the test probes, and then read the voltage measurement.
- To get the most stable measurement, press the "hold" button. You will see it after the voltage measurement is completed.
- Press the "MIN/MAX" button to get the lowest and highest DC voltage measurement, press the "MIN/MAX" button. Wait for a beep each time the DMM records a new voltage value.
- If you want to set the DMM to a predetermined value, press "REL" (Relative) or "?" (Delta) buttons. The display will show voltage measurements below and above the reference value.
How to measure DC voltage with an analog multimeter
Follow these simple steps:
- Press the "ON" button on your meter to turn it on.
- Turn the multimeter knob to the "V" positionDC» – DC voltage. If your analog multimeter does not have "VCOLUMBIA REGION,” check if there is a V with a straight line of 3 points and turn the knob towards it.
- Proceed to set the range, which must be greater than the expected test voltage range.
- If you are working with an unknown voltage, the set range should be as large as possible.
- Connect the black lead to the COM jack and the red lead to the VΩ jack (preferably the one with VDC on it).
- Place the black probe on the negative or lower voltage point and the red probe on the positive or higher voltage point.
- For maximum deflection, which helps improve accuracy, decrease the voltage range.
- Now take a VDC reading and be careful not to take a VAC reading.
- After you have finished taking readings, remove the red probe first and then the black probe.
- Turn off the multimeter and then set the maximum range to prevent damage in case of rapid reuse.
Unlike a digital multimeter, an analog multimeter does not warn you of reversed polarity, which can damage the multimeter. Be careful, always respect the polarity.
What is an overload condition and when does it occur?
There is a good reason why you are advised to select a voltage range above the expected value. Selecting a lower value may result in overload. The meter cannot measure voltage when it is outside the measuring range.
On a DMM, you will know you are dealing with an overload condition if the DMM reads "out of range", "OL" or "1" on the screen. Don't panic when you get an overload indicator. It cannot damage or damage the multimeter. You can overcome this condition by increasing the range with the selector knob until you reach the expected value. If you suspect a voltage drop in your circuit, you can also use a multimeter to measure it.
When using an analog multimeter, you will know that you have an overload condition if you see the "FSD" (Full Scale Deflection) arrow. In analog multimeters, overload conditions must be avoided to prevent possible damage. Stay away from low voltage ranges unless you know how to measure voltage.
Safety advice: Avoid sensors with broken or bare wires. In addition to adding error to voltage measurement readings, damaged probes are dangerous for voltage measurements.
Whether you are using a digital multimeter or an analog multimeter, you now know how a multimeter measures voltage. Now you can measure current with confidence.
If you give your full attention to the process, you are ready to measure voltage from a DC source. Now measure the voltage from your preferred DC source and see how it works.
We have listed a few more multimeter tutorials below. You can check and bookmark them for later reading. Thank you! And see you in our next article!
- How to check battery discharge with a multimeter
- How to use a multimeter to check the voltage of live wires
- Cen-Tech 7-Function Digital Multimeter Overview
Recommendations
(1) electrons - https://whatis.techtarget.com/definition/electron
(2) electrical energy - https://www.sciencedirect.com/topics/engineering/electrical-energy
