I used a Klein NCVT-3 on a live circuit and it gave me a false negative

I was working on a panel in an old house in Spokane last month, and my non-contact tester didn't beep on a wire I was sure was hot. I went ahead and touched it to double-check, and got a good jolt. I learned that those testers can fail if the wire is buried in a crowded conduit or has certain types of insulation. Has anyone else had this happen, and what's your backup check method now?

3 comments

3 Comments

grant_palmer1mo ago

Actually, I've found those testers to be super reliable if you use them right. You gotta make sure you're holding it correctly and that the battery isn't dead. I'd trust mine before I'd just go touching a wire.

sethc125d ago

Which exact model do you have?

craig.parker1mo ago

My old Fluke tester has a low battery light that's saved me a few times. @grant_palmer, what specific brand or model do you use that you find so reliable? I'm curious if they have a similar feature or if you just do a quick check on a known live circuit first.