8 Different Types of Electrical Testers and How to Choose One

Non-Contact Voltage Tester (Inductance Tester)

Yellow non-contact voltage tester inserted into 120-volt outlet receptacle

The Spruce / Kevin Norris

  • Best for: Detecting and measuring voltage

Non-contact voltage testers (also known as inductance testers) allow you to check for voltage in wires or devices without you having to touch any electrical parts. They are safe, easy to use, and inexpensive. 

The device is like a mini wand with a small tip on the end that senses voltage in such things as electrical wiring, outlets, circuit breakers, lamp cords, light sockets, and switches. You can get a reading simply by sticking the tip of the tester into an outlet slot or even touching the outside of a wire or electrical cable. 

Most models inform you of the voltage present with a red light at the tip of the tester as well as a buzzing sound. The most basic models indicate only whether any voltage is present. More sophisticated (and more expensive) types provide a rudimentary measurement of how much voltage is present, though the measurement is not nearly as precise as that offered by certain other electrical testers.

Tip

Non-contact voltage testers are typically battery-powered. And it’s important to ensure that the battery is fully charged to know the device is working properly. Always test the device on an outlet or switch you know has power to it to verify that the tester is working.