How To Use an Electric Voltage Tester

In this video, Kevin O’Connor meets master electrician Heath Eastman at the shop to discuss the different types of voltages testers and their uses. Heath has four types of testers to show Kevin, including a non-contact pen tester, a full-size multimeter, a miniature multimeter, and a plug-in tester. Heath explains how each tester works, which scenarios they’re best for, and how he uses them in his work line.

Types of Electric Voltage Testers

Contactless Voltage Tester

A contactless voltage tester is shaped like a pen or marker, and it can indicate whether a wire or outlet has voltage feeding it. They’re quick and easy to use, and they can help an electrician or homeowner locate live circuits. However, they don’t tell the user how much voltage the outlet or wire has, and they’re not always completely accurate.

Full-size Multimeter or Contact Tester

A full-size multimeter might be overkill for homeowners, but they can tell an electrician a lot about an outlet, switch, fixture, or circuit. These voltage testers have two contact points or probes that the user can touch to the circuits’ wires to determine the amount of voltage, amperage, and resistance on the line. If the pen tester alerts a circuit having a charge, a contact tester is the best way to find out why.

Small Contact Testers

A homeowner doesn’t necessarily need a full-size multimeter, but a small contact tester can do much of the same work. These scaled-down meters have two contact points or probes, and they explain the voltage on a system in ranges, such as 24 volts, 48 volts, 120 volts, and 240 volts. They’re more affordable than full-size meters and much more compact. They’re also one of the only options for 2-prong outlets.

Receptacle Testers

Receptacle testers are compact and easy to use, and they provide a lot of information. While they don’t explain how much voltage a receptacle is experiencing, they do explain if there is an open ground, an open neutral, or an open hot.

They can also indicate polarity, or whether the hot and ground are reversed, or (more commonly) if the hot and neutral are reversed. These testers will only work on 3-prong outlets, and they can test GFCI outlets, as well.

Pros and Cons of Voltage Testers

All types of voltage meters have their pros and cons, and it could be worth keeping a few types of testers in your tool bag. While the receptacle tester is the only tester that tests polarity, it can’t quantify voltage or test two-prong outlets. Pen testers or contactless testers don’t explain voltage either, but they’re fast and easy to use. For the best results, have a few of these testers on hand before doing electrical work.