A non-contact voltage tester is the safest way to make sure the power is off without touching any wires. Non-contact voltage testers work by detecting the changing electric field around objects conducting an AC current (AC stands for “alternating current”).
Before you open an electrical box, you should cut off power to the outlet at the main electrical panel and confirm that you turned off the right circuit.
This is where the non-contact voltage tester comes in handy. The tester will light up and/or make noise when it comes close to a hot (live) wire, even one that’s covered in plastic insulation. Note that it can’t test through metal conduit or metal sheathing.
Non-contact voltage testers (also known as voltage tester pens, test pens, or voltage sensors) are the safest way to detect the presence of AC voltage and ideal for testing power cables, circuit breakers, wall outlets, junction boxes, and fuses.
Operating Power: 2 AA Batteries
Measuring Voltage: 90V ~ 1000V (AC)
Operating Temperature: – 10℃ ~ 50℃
Storage Temperature: -10℃ ~ 50℃
Operating Humidity: 80% RH
Pollution Index: 2
Method of Use: Non-contact electric pen
Cleaning Methods: Wipe with a damp cloth