This is a non-conductive (plastic), non-contact voltage sensor that glows red and/or beeps in the vicinity of an energized conductor. In other words, it lights up near a "live" wire. You don't actually have to make contact to see if the line is hot. It lights up even if there is no load on the line, since it senses the electric field, not the magnetic field. It's much easier to use than a contact indicator light or meter. It works for AC line voltages. Also it only lights up when near the "hot" line, not the ground or neutral, so you can immediately see if an outlet is wired backwards. Works great for finding the dead Christmas light bulb on a series string of lights too (not as easy though when you have two or more strands braided together.) I always rub it against my shirt first to see if it is working. Static discharge sets it off. A number of vendors besides Fluke make this type of device, but Fluke is a high quality name brand.

-- Bruce Bowen

Fluke Voltalert
90VAC to 600 VAC
$23
Available from Amazon

Manufactured by Fluke