How to Test Electrical Wires with Multimeter?

Multimeters are also known as electrical testers. You can test almost every electrical appliance with it. All electrical appliances have plenty of wires. Some of them are for power, and some of them are for control.

Now the question arises of how to test electrical wires with multimeter. Don't worry its quite simple.

For safe electrical wire testing with a multimeter, follow these steps: Turn off power, wear safety gloves, set multimeter to 250V AC, then probe wire; if 110-120V, it's live. 

There are 5 easy steps to test any electrical wire. Let's have a look,

5 Steps To Test Electrical Wires with Multimeter

Testing electrical wires with a multimeter ensures safety and functionality. The process involves five essential steps. First, ensure the multimeter is set to the correct mode. Second, disconnect power to the circuit. Third, select the appropriate probes. Fourth, test for voltage and continuity. Finally, interpret the readings accurately for troubleshooting and repairs.

how to test electrical wires with multimeter


1. Isolation of Electrical Wires

The first thing you have to do before testing any electrical wiring is to disconnect its power. In the same way, if you want to troubleshoot any control wiring, then remove input and output connections. If you do not isolate the wires from the system, then it's difficult to trace the faulty wiring. You can check our best fluke multimeters for electrician.

2. Right Multimeter For the Right Job

Most people just grab any multimeter and start troubleshooting. This is not the right way because by doing this, you're risking the system and your own life. If you want to measure high voltages, then you must go for the best multimeter for electricians.

In the same way, for lower ranges, you can select the best multimeter for electronics technicians. Luckily some all-in-one multimeters can do all electrical and electronics testing. Amprobe AM-530 is one of them.

3. Selection of Right Variable

If you're wondering how electricians test electrical wires with a multimeter, then the answer is simple with the right knowledge and practice. First of all, you have to rotate the dial on continuity. After this, connect both test leads to double-check if you hear the beep sound. After that, it means you're good to go.

DIAL OFMULIMETER

4. Selection of Test Leads

Test leads play an essential role in getting precise values. Set multimeter to 250V AC. There are different test leads for various purposes. CAT-II test leads are used for Medium voltage measurement. However, CAT-III test leads are used for low voltage equipment. To test electrical wires with multimeter CAT-III test leads are good enough.

5. Know the Test Points

You must know that where multimeter test leads should be connected. If you place both the leads on same path then it may causes damage. Most of the time beginner's don't know how to test electrical wires with multimeter. There are different procedures for both live and dead circuits. Each of the testing method is mentioned below.  

What is Hot/Live Electrical Wire Test?

Industrial or commercial electricians can not shut the system. In such cases, I always recommend beginners to get professional support from senior electricians. You can also grab the best fluke multimeter for electrical work with just a single click.However, you can test live electrical wires with a multimeter also.

  • For this purpose, you have to select the maximum voltage ranges and put the negative (Com) test leads on earth.
  • After this, you have to follow an electrical wiring diagram and follow the Positive path with the test lead positive terminal (V). you will get the voltages on display.
  • While tracing the circuit where the supply will disconnect, note that wire or equipment. Congrats, you have found the faulty area. Now you can either replace or repair it.

How To Test Disconnected Electrical Wires?

If you are here, it means you are facing a problem with your electrical wiring. To check electrical wire in a dead state is not difficult. You just have to set the dial to continuity and insert the probes in (V) and (Com). Next, connect one probe to one end of the wire and then trace the other end where the beep breaks; just check there. Congrats, you have found the weak point.

Safety Guidelines While Testing Electrical Wires with Multimeter

There are multiple things one should consider before checking the wires.

  • The first and foremost important thing is to place your multimeter before and after use in a dry place.
  • Don't drop your multimeter; otherwise, it will start malfunctioning.
  • Always check voltages to some standard source to check whether it's working correctly or not. You can also use the Fluke proving Unit to check your multimeter calibrations.
  • You should know your working ranges. But if you have an auto-ranging multimeter, then you may take a rest.
  • Always choose the suitable test leads for high voltages, cat-ii standard, for medium voltages cat-iii standard and for electronics, use the cat-iv standard test leads.
  • Never buy any digital multimeter without fuses. Because it's the safety fuses that save you and your multimeter in case of an accident.

Always make a habit of checking voltages in any circuit before checking any other electrical variable.

How To Measure Current in Electrical Wires with a Multimeter?

So, how to test electrical wires with multimeter? If you want to check current with a multimeter, then it can be done with multimeter probes. But it only limits to 10A. Some good quality digital multimeters can measure current up to 20A.

how to test electrical wires with multimeter
  • First of all, select the AC/DC option.
  • Secondly, to check current with a multimeter, you just have to insert the test leads in (A) and (com) positions.
  • Lastly, After test leads insertion, you can connect the leads on each phase and neutral. The running current will be shown on your display.

But if you want to measure a higher current in electrical value, use a clamp meter. You just have to clamp the electrical wire in the clamp meter, and the results will be on your display. The only precaution is that you can clamp only each phase at one. If you want to know more about the best clamp meters and how to use them, then you can check my clamp multimeter blog.

Conclusion:

So, this is how to test electrical wires with multimeter. I hope you found this information helpful. If you want to check the current with a multimeter, then it can be done with multimeter probes. But it is only limited to 10A. Some good quality digital multimeters can measure current up to 20A. If you want to measure higher current values, then you can use a clamp meter. I have dug down some of the best clamp meters for you let's take a look at them also. Thanks for reading!