Test Electric Current: A Must-Read Guide For DIY Enthusiasts

Before doing any electrical repairs, it’s essential to identify the appropriate tools for the task. There are many options available designed to test electric current. You’ll need to determine whether the current is energized and whether any endpoints or feed-throughs are powered. In some situations, you might also need to calculate voltage levels to ensure everything is functioning properly grounded.

The good news is that most homeowners can handle this without too much trouble. Testing an outlet can be as simple or as advanced as you need it to be. You could use a working bulb for a basic approach or turn to highly specialized and expensive equipment.

How do you test electric current?

To test electric current, you can use an ammeter, which is a device that measures the flow of electric current in a circuit. Here are the steps to test electric current using an ammeter:

Turn off the power supply to the circuit you want to test.
Open the circuit by disconnecting one of the wires.
Connect the ammeter to the circuit by placing the ammeter in series with the wire that was disconnected in the previous step. This means that the current will flow through the ammeter before it continues through the circuit.
Turn on the power supply and observe the reading on the ammeter. The ammeter will show the amount of current flowing through the circuit, usually measured in amperes (A).
If the ammeter reading is zero, it means that there is no current flowing in the circuit, or the ammeter is not properly connected. Check the connections and try again.
It is above the expected range (the ammeter reading), which may indicate a problem with the circuit or an overload. Check the wiring and components in the circuit to identify the problem.
After testing, turn off the power supply and disconnect the ammeter from the circuit.

How do I test if a wire is live?

Testing, if a wire is live, can be done using a voltage tester or a multimeter. Here’s how to test if a wire is live using a voltage tester:

Turn off power to the circuit you are testing by switching off the breaker or removing the fuse that powers the circuit.
Insert the probe of the voltage tester into the small opening on the end of the tester.
Hold the voltage tester by the insulated handle.
Touch the metal tip of the voltage tester to the exposed wire you want to test. Be sure to avoid touching the wire with your bare hand, and hold the probe by the insulated handle to prevent electrical shock.

The majority of electrical cables have three main conductors: positive, neutral, and earth. The tension gauge only indicates the presence of current when it is in contact with a hot or positive cable.

It is necessary to check the cable using a multimeter or a UWB device.

If the wire is live, the voltage tester will light up or emit a sound, indicating the presence of voltage. If the wire is not live, the voltage tester will not light up or make a sound.

After testing, turn on the power supply and ensure that everything is functioning properly.

How do you test if a wire is live with a multimeter?

A multimeter is an indispensable tool for any electrical hobbyist or simply for people who like to do repairs or maintenance. It may look intimidating but once you learn how to use it you have a myriad of useful functions.

Turn off power to the circuit you’re testing by light switch off the breaker panel or removing the fuse.
Set the multimeter to the voltage setting that is appropriate for the voltage level of the circuit you are testing. For example, if you are testing a 120-volt circuit, set the multimeter to the 200-volt AC range.
Insert the probes into the appropriate ports on the multimeter. The red probe should be inserted into the port labeled VωmA, this indicates that tester is working.
Hold the tester by the insulated handle and touch the metal probe to the wire.
If the wire is live, the tester will light up or emit a sound to indicate that voltage is present.
After testing, turn the power back on and ensure everything is working properly.

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, resistance, continuity, and currently less than 200mA. and the black probe should be inserted into the port labeled COM.

Hold the probes by the insulated handles.
Touch the black probe to a ground wire or metal surface that is grounded, such as a metal conduit, junction box, or the ground prong of an electrical outlet.
Touch the red probe to the wire you want to test.
If the wire is live, the multimeter will display a voltage reading. The voltage reading should be within the range of the multimeter setting you chose in Step 2. If the wire is not live, the multimeter will display zero or a very low voltage reading.
After testing, turn on the power supply and ensure that everything is functioning properly

Types of Electrical Testers

There are different types of electrical testers that can be used to test electrical circuits, components, and systems. Here are some common testers used for electrical work:

Voltage testers

They are used to test the presence of voltage in a circuit. They are available in different types, including non-contact voltage testers, which detect voltage without making contact with the circuit, and contact voltage testers, which require direct contact with the circuit. Voltage testers are best for quick and simple tests, such as identifying a live wire or checking the voltage level of a battery.

Multimeters

They are versatile testing electrical tools that can measure voltage, current, resistance, and continuity in a circuit. They come in both analog and digital forms, and they can be used for a wide range of electrical testing tasks, such as testing the resistance of a component or measuring the current flowing through a circuit. Digital multimeters are more accurate and easier to read than analog ones, making them the preferred choice for most users.

Continuity tester

These testers are designed to test if a circuit is complete, ensuring no breaks in connections.

Clamp meters

They are used to measure the current flowing through a conductor without breaking the circuit. They have a clamp-like design that allows them to be clamped around a wire, and they can measure both AC and DC currents. Clamp meters are best for testing the current in high-power circuits, such as those found in industrial and commercial settings.

Circuit tracers

Used to locate and trace the path of electrical wiring in a building or system. They consist of a transmitter and a receiver, and they work by transmitting a signal through the wiring that can be detected by the receiver. Circuit tracers are best for troubleshooting complex electrical systems, such as those found in commercial buildings or industrial facilities

How to choose one

You can’t pick one, in the sense of just having it as a tool. You should have them all because each one serves a function. Depending on the project you are on, for example, if you just need to know if there is voltage, you only need a basic contact voltage tester. If you are going to do more demanding jobs, you will need a multimeter.

In my case, I tell everyone that with a multimeter they will fly, because if you know how to use it and program it you have all the tools.

Regardless of your skill level, having a good understanding of your tools ensures your electrical work is both efficient and safe.

Bottom line

You must buy an electric tester regardless of the electric project you are handling. Ensure you use tools that are designed to test electrical systems, such as voltage testers, continuity testers, or a multimeter, depending on the task. Remember to verify that your setup is properly grounded and confirm that all components, from the breaker panel to live wires, are working properly. If you’re unsure about your abilities, don’t hesitate to consult a professional to ensure safety and accuracy.

Written by Vanessa Gallanti. May 4, 2023

Enthusiast about planning, project management, construction materials and technology, and construction. A civil engineer from Los Andes University and a content writer for Kukun.