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Energy CostsIN CHARLOTTEMay 5, 2022by AndrewHow to Use a Multimeter to Measure Voltage, Current and Resistance

What is a Multimeter?

A multimeter is a useful tool for determining electrical power, much like you would utilize a ruler to measure distance, a stop watch to gauge time, or a scale to know weight. The cool thing about a multimeter is unlike a ruler, watch, or scale, it can gauge various points. It’s actually a type of multi-tool. A lot of multimeters have a handle on the front that lets you choose what you intend to measure. There are various multimeter models.

What Do Multimeters Do?

Most multimeters can determine voltage, current and resistance.
Some multimeters have a continuity check, resulting in a loud beep if two things are electrically attached. This is handy if, as an example, you are developing a circuit as well as linking wires or soldering. The beep shows every little thing is attached and nothing has actually come loose. You can likewise utilize it to ensure two things are not linked, to make sure about avoiding short circuits.
Some multimeters also have a diode check function. A diode resembles a one-way valve that only lets electricity flow in one direction. The specific feature of the diode check can differ from multimeter to multimeter. If you’re working with a diode however do not know which way it goes in the circuit, or if you’re not sure the diode is working effectively, the check function can be rather useful. If your multimeter has a diode check function, read the manual to figure out specifically how it functions.
Advanced multimeters may have other features, such as the capability to gauge and recognize various other electrical elements, like transistors or capacitors. You can read your multimeter’s manual if you need to know more about these functions.

How to Use a Multimeter to Measure Voltage, Current and Resistance
Most multimeters can determine voltage, current and resistance.

What’s Voltage, Current and Resistance?

If it’s been awhile since high school science class, or are unsure about what these electrical terms really mean, we’ll go into a pretty basic introduction here. Keep in mind that voltage, current and resistance are measurable amounts that are each measured in a system. Each term has a symbol and a measurement unit, just like distance is a quantity that can be determined in feet or meters, and the icon for meters is m.
– Voltage is exactly how much electrical energy is being moved through a circuit. A greater voltage suggests the electrical power is being moved with more force. Voltage is determined in volts. The sign for volts is V.
– Current is just how much power is moving through the circuit. A higher current tells you extra power is flowing. Current is measured in amperes. The sign for amperes is A.
– Resistance is just how hard it is for electrical power to flow through something. A higher resistance means it is harder for electrical power to circulate. Resistance is gauged in ohms. The sign for ohms is Ω (the Greek letter omega).

How Do I Measure Voltage?

To get voltage, follow these steps:

  1. Plug the black and red probes into the correct sockets (or referred to as “ports”) on your multimeter. For the majority of multimeters, the black probe needs to be plugged into the outlet classified “COM” and the red probe goes into the outlet identified with a “V” (it could have some other symbol).
  2. Choose the correct voltage setup on your multimeter’s dial. Remember that most battery-powered circuits will have direct currents, however the setup you pick will depend upon the job you are doing. If you are working with a manual-ranging multimeter, you can estimate the range you require based upon the battery (or batteries) powering the circuit. As an example, if your circuit is powered by a single 9V battery, it probably does not work to choose the setup for 200V, as well as 2V would be too weak. If available, you would want to set it to 20V.
  3. Touch the probe pointers to the circuit in parallel with the component you wish to gauge voltage throughout. Be sure to utilize the red probe on the side connected to the positive battery terminal, as well as the black probe on the side attached to the negative battery terminal. Nothing will certainly be hurt if you get this in reverse, however your voltage reading will be negative.
  4. If your multimeter is not auto-ranging, you may need to change the range. If your multimeter’s display is always “0,” the range you have set is probably too high. If the display views “OVER,” “OL,” or “1” (these are different methods of stating “overload”), then the range you have chosen is too low. If this takes place, change your range setting up or down as needed. You might need to consult your multimeter’s guide for specifics about the model.

How Do I Measure Current?

To get the current, follow these steps.

  1. Connect the red and black probes into the right outlets (also referred to as “ports”) on the multimeter. For a lot of multimeters, the black probe needs to be plugged into the outlet called “COM” There may be multiple ports for measuring current, with names like “10A” or “mA”. Keep in mind, it is always safer to start out with the socket that can gauge a bigger current. Plug the red outlet into the high-current port.
  2. Set the correct setting on the multimeter. You need to check if the circuit is a direct current or alternating current. If your meter is not auto-ranging, you may have to guess at the scale, but then you can adjust this later on if you don’t get a useful reading.
  3. Link the multimeter probes in series to the current you need to measure. Make certain to utilize the red probe toward the battery’s positive end or else the current reading will read negative.


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