Last Updated on October 22, 2023 by Kevin Chen
Knowing how to use a multimeter to measure current is frequently required. Although performed somewhat differently than voltage and other measures, current measurements are simple. However, current measurements are commonly needed to determine whether a circuit is running correctly or learn further details about its current usage.
Because the current is one of the most fundamental electrical and electronic properties, it is frequently required to measure the current flowing in a circuit to ensure it operates properly. Current measurements can be conducted with various test instruments, but the multimeter is the most commonly used piece of test equipment for current measurements. These pieces of testing equipment are generally available and inexpensive. We will learn how to utilize a multimeter in this article.
What is Electric Current?
Current refers to the rate at which charge flows. Amperes are the units of measurement (Amps). The direction of AC changes continually, whereas DC only travels in one direction. Ammeter is the name of the meter that is used to measure current.
Because the current is the flow of charge, we require the current to flow inside the meter when measuring it. As a result, the circuit must be opened at the moment of measurement, and the meter must be inserted in line with it. On the other hand, the clamp meter allows you to measure current without opening the circuit.
What is a Multimeter?
Professionals in various fields rely on multimeters, including research, appliance maintenance, industrial testing and maintenance, and electrical installation. A multimeter is a piece of valuable test equipment for home and DIY projects. The instrument can be used to measure current, voltage, and resistance, as well as check the following:
- Vehicle electrics and electronics
- Battery voltages
- Continuity of cables and power cords
- Home appliances and electronic devices
What Is A Multimeter Capable Of Measuring?
Current, voltage, and resistance can all be measured with almost any multimeter. If two things are electrically connected, certain multimeters have a continuity check, which results in a loud beep. This is useful if you’re soldering or joining wires in a circuit; the beep shows that everything is linked and nothing has fallen loose. It can also ensure that two things are not connected to avoid short circuits.
A diode check option is also available on some multimeters. A diode functions similarly to a one-way valve, allowing electricity to flow only in one direction. The diode check’s exact function varies from both multimeters. If a diode is what you are using and can’t figure out the side it belongs in a circuit or aren’t sure if it’s operating properly, the check option comes in handy.
Other features of advanced multimeters include measuring and identifying other electrical components such as transistors and capacitors. We won’t go through these capabilities in this article because they aren’t available on all multimeters. If you need to use these features, consult your multimeter’s manual.
The Basics Of Current Measurements
Current measurements differ from voltage and other types of sizes. The flow of electrons via a circuit is described as current, and the capacity to monitor the overall flow of electrons is essential.
The following is a very simple circuit. A battery, a bulb that can be used as an indicator, and a resistor are all included. The resistance can be changed to alter the amount of current flowing in the circuit, and the amount of current flowing can be determined by the bulb’s brightness.
The only way to detect the amount of current flowing when using a multimeter to measure current is to break into the circuit so that the current goes through the meter. This is the greatest option, even though it might be challenging.
When measuring current, the multimeter’s resistance should be as low as possible so that it does not affect the operation of the circuit. The resistance of a meter should be substantially lower than an ohm for measurements of around 1 amp. For example, a meter with a resistance of one ohm and a current of one amp would create a voltage of one volt across it. This is excessively high for most measurements. As a result, current meters have very little resistance.
How Do You Measure Currents With an Analog Multimeter?
It’s simple to measure electrical current with an analog meter. Even though there are a few minor changes to the way Current measurements are taken, the underlying concepts remain the same.
When using an analog multimeter, there are a few easy steps to follow:
- The probes must be inserted into the correct connectors; this is necessary because several different connections might be used. Ensure you have the right links, as there may be different ones for extremely low and very high current ranges.
- Set the switch to the appropriate measurement type (current measurement) and range for the measurement. When choosing a range, make sure the maximum is higher than you expect. If necessary, the multimeter’s range can be lowered afterward. However, selecting a range that is too high protects the meter from becoming overloaded and causing damage to the meter’s movement.
- Optimize the range when taking the reading to get the best result. Adjust it as far as possible to achieve the meter’s maximum deflection. The most precise reading will be obtained in this manner.
- After reading, insert the probes into the voltage measuring sockets and set the range to maximum voltage. The meter will be less likely to be damaged if accidentally attached without considering the range to be utilized. This may not be the case if the meter is mistakenly connected across a high voltage point while configured for current reading.
How Do You Measure Current With A Digital Multimeter?
Using a digital multimeter to measure current can be highly risky. Use extra caution in this situation. Always handle cables as if they have power.
- Connect your leads to the appropriate ports on your multimeter to measure current. The “A” port is where your red information is plugged in. Your red lead will connect to your “mA” port for modest currents.
- Always start with the A port when taking current measurements. A port for measuring modest quantities of current will be available on some multimeters. “mA” is the name of this port. Use the mA port only if you’re sure the current isn’t too high. When you use the mA port with many currents, you risk getting hurt.
- If you’re measuring AC Current, wave your hand over the top of the dial and aim it towards the letter “A.” If you’re measuring DC Current, make a straight & dashed line on top of the dial and point it towards “A.”
- You can’t simply place your probes on the circuit to measure current. The multimeter leads must be connected to the circuit in series. Remember that current can only travel in one direction in a series circuit.
- To measure current, connect the meter leads to the circuit in series. You’ll need to turn off the power to do this. This is a potentially harmful step. Use a clamp meter rather than a digital meter if possible. You don’t have to disconnect a circuit to use a clamp meter.
- Turn off the electricity to the circuit before connecting your multimeter in series. Continue to act as if the circuit is powered on after the power has been turned off. Measure the voltage of the circuit to ensure that it is de-energized. You can proceed if there is no voltage.
- Disconnect the wire that connects to the component you’re inspecting. Now there should be a gap in the circuit. Connect one of the multimeters leads to the detached wire’s end. The other lead should be pressed into the component’s wire connection
- After safely connecting your multimeter in series, turn the power back on. If you touch any live wires, you could die. Maintain control by keeping your probes as far away from the metal tips as feasible.
- The current should be displayed on your multimeter. The units will also be displayed on the multimeter’s display.
How To Measure Current Using A Clamp Meter?
The most simple and secure measuring current is with a clamp meter. When using a clamp meter, you don’t need to touch any wires. This minimizes the risk of harm greatly. Let’s begin by learning how to measure current with your multimeter dial.
Remember that current is divided into two types: AC and DC. Keep in mind that the flow direction in AC alternates. Only one way of DC flows. The type of system will be indicated on the schematic diagram for the equipment.
If you’re measuring AC current, wave your hand over the dial and point it to the letter “A.” When measuring DC, make a straight and dashed line on top of the dial and point it towards “A.” Setting the meter to AC or DC may require pressing the yellow function key.
You won’t need multimeter leads because you’ll utilize the clamp to measure the current. Remove all multimeter leads from your multimeter.
The left-hand side of the multimeter has a button. Press it. The clamp jaws will now open. Release the button to close the jaws after moving the multimeter such that one wire is inside the clamp. During this process, don’t touch the wire. The multimeter is the only thing you should be moving.
Position the wire in the center of the clamp once it is inside your closed meter. The wire should not contact the clamps or multimeter surrounding edges. The multimeter’s display should show the current and unit. 200mA, for instance.
Remember that a live wire is connected to a power source. Do not touch the wire you’re measuring when using a clamp meter. The lower part of the meter should be in your hand. The more away you put your hand from the live wire, the safer you are.
Always set the meter to read voltage once you’ve finished using it. Grabbing a meter and quickly measuring the voltage between two pins is typical.
You won’t be able to see the voltage on the display if your meter is in ‘current’ mode. Instead, you’ll observe ‘0.000,’ which means there is no current flowing between GND and VCC. You’ll have linked VCC to GND through your meter in a fraction of a second, causing the 200mA fuse to explode which is bad. Before shutting off your meter for the night, remember to leave it in a friendly state.
For more details on currency measuring components or other electrical components, contact us at ICRFQ. We manufacturer the best electrical components.
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