ECN Forum Forums General Topics of the Trade General Discussion Area non-contact voltage testers

Would anybody trust a non-contact voltage tester? (such at the Fluke 1AC-A1, the pen shaped testers that glow in the presence of voltage and fit in your pocket) Would you trust it enough to touch a bare wire or terminal strip that nomally has 600 vac. on it if the "volt pen" showed no presence of voltage? This has became a recommended practice here at the mill. I think you need a contact type tester in this situation.
Comments? Thanks

I wouldn't touch a 600v conductor if every piece of equipment in town said it was dead unless I had the fuses in my pocket or the key to a locked-off disco. Get the mug with the non-contact doo-hickey to do it!

I agree with Alan I would have to have my lock on and test the circuit myself with a meter that was tested on a known hot circuit to verify that it works.

What is it's purpose if not to check for voltage?

I always check that it is working either with a known live circuit or simply rubbing it on my sleeve. It will light if it's operational. I have never had it read dead on a live circuit, it will sometimes give a false live reading.

I carry the Fluke non contact tester and a Fluke T5-1000 Multimeter. I am not sure which is more reliable, they both rely on electronics to produce a correct reading.

Bob

I've never known the Fluke Volt Alert to give a false "dead" reading. I test mine the same way that Bob does.

BTW, if you want to be thourough, you should also test your meter on a known live circuit after you use it to check for voltage on a circuit you want to work on. You never know exactly when your meter will quit working.

Tom

I agree with iwire, test by either using a known AC voltage source, or by rubbing on your sleeve or other part of your clothing, before AND after checking the terminal in question. If there is any chance it may be falsely registering no voltage, for example due to a preponderance of grounded metalwork, I would revert to a contact voltmeter of some kind. But generally, I have found the non contact kind very reliable if treated well. I was always taught that the 'prove your tester actually works both before and after testing an unknown conductor/terminal' routine, and it makes sense to do so with both non contact and traditional testers.

I've found them much more likely to give false positives than a false "dead" reading. They have their place, but they aren't a substitute for a good meter or volt con.

I have the Fluke pen-shaped tester. Its a standard-issue item in our company.

347V or 600V lights the thing up from several inches away... and gives a false positive when you have other live conductors in the same conduit.

After I have used my tester, removed the fuses or whatever else I need to do to be sure it is dead, I am still grounding that wire before I touch it. Wear your safety glasses ;-)

"I am still grounding that wire before I touch it. Wear your safety glasses "

Yeah, wear your safety glasses. While it's a definately reliable way to make sure it's dead, what a fireworks show, guess it's still better than being dead though. Be careful!