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Old 07-06-2009, 06:56 PM   #16
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Better yet, it almost looks like it turned the cutters into a serviceable wire stripper, even Steven.
Thats what my helper said "Now you can strip #6 wire"
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Old 07-06-2009, 08:20 PM   #17
 
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Non-contact voltage testers can give a false negative if the device in question is connected to a good ground. They work by picking up the magnetic field that is induced in whatever device you are trying to check, which can be absorbed by said grounded conductor. This is why they will often give a false negative on a hot switch. Non-contact testers(we call them "ticks") are good to have, but definitely should not be given the final say so. As mentioned before, wiggy's are better, but are a little less convenient. Any time you are in doubt, break out the wiggy or multimeter just to be safe.

In response to the OP's question, I agree that you should be ok touching it to anything you would find in residential work.

On a side note, I had an old timer tell me once to flick it with your fingernail as a final check AFTER you've ticked it or meter'd it. You finger nail has a higher resistance than bare flesh. I've never tried that personally, so proceed at your own risk.
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Old 07-06-2009, 08:26 PM   #18
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Originally Posted by Atroxx View Post
Non-contact voltage testers can give a false negative if the device in question is connected to a good ground. They work by picking up the magnetic field that is induced in whatever device you are trying to check, which can be absorbed by said grounded conductor. This is why they will often give a false negative on a hot switch. Non-contact testers(we call them "ticks") are good to have, but definitely should not be given the final say so. As mentioned before, wiggy's are better, but are a little less convenient. Any time you are in doubt, break out the wiggy or multimeter just to be safe.

In response to the OP's question, I agree that you should be ok touching it to anything you would find in residential work.

On a side note, I had an old timer tell me once to flick it with your fingernail as a final check AFTER you've ticked it or meter'd it. You finger nail has a higher resistance than bare flesh. I've never tried that personally, so proceed at your own risk.
Just to correct some minor nits, it's the induced capacitive electric field the device senses, not magnetic. And that old time crap is bunk in more ways that one:

1) You are asking to get yourself hurt,
2) You have to be grounded in some manner to complete a circuit and feel it.

If you are wearing shoes, and you are on dry ground, and only touch the wire with one hand, you will not know if it is live or not.
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Old 07-06-2009, 08:31 PM   #19
 
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Ehh, true, but like I said, it is intended as a final check, after the tick or meter calls it safe. It was probably thought up by some old electrician who was a little skittish around electricity. As a final check only, if your going to get shocked either way, then that's probably going to cause you the least amount of pain/injury.

Again, I am stressing that the fingernail check is much less reliable than a tick would ever be, but it can make you feel better about what you're about to grab a hold of if you don't completely trust your equipment.

Last edited by Atroxx; 07-06-2009 at 08:33 PM.
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Old 07-07-2009, 11:16 AM   #20
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Again, I am stressing that the fingernail check is much less reliable than a tick would ever be, but it can make you feel better about what you're about to grab a hold of if you don't completely trust your equipment.
Sound like the same people who brought us waterboarding. . .

"United States Patent 7330755
Abstract:
An apparatus for preparing a finger nail or a toe nail for a coating in that a gas discharge is ignited above the nail at atmospheric pressure comprises an electrode to be arranged above the nail, and a high voltage generator generating a high voltage to be applied to the electrode arranged above the nail for igniting the gas discharge between the electrode and the nail."
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Old 07-07-2009, 01:37 PM   #21
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Depends on the state of the battery, and the condition the contacts to the battery are in. Sometimes, especially on the Greenlee tester, you will turn the thing on, but it isn't really on, because of corrosion on the battery, and it won't read. For this reason, you either test it on a known hot, or rub it on your shirt or hair, because the static will cause it to chirp if it is working.
I also get alot of false negatives with wet NM/romex.
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Old 07-08-2009, 06:26 PM   #22
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Originally Posted by Atroxx View Post

On a side note, I had an old timer tell me once to flick it with your fingernail as a final check AFTER you've ticked it or meter'd it. You finger nail has a higher resistance than bare flesh. I've never tried that personally, so proceed at your own risk.
When I was taking "House Wiring 101", our instructor would check our receptacle hookups by putting his thumb and forefinger across the hot and neutral screws. I watched him do it, don't know how he could stand doing it, and always thought he was an idiot for doing it.

Always makes you a little leery of the quality of the class when your instructor pulls something like this.
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Old 07-08-2009, 06:31 PM   #23
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\always thought he was an idiot for doing it.
But a macho idiot. . .
I wonder if he eventually got nerve damage to his hand.
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Old 07-08-2009, 08:59 PM   #24
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Some of you might already know this, but when using a "glow stick" or non contact tester. If you put your finger on the end and put the other side against the wire it will cut down on false readings. I'm talking about insulated wire, not bare.
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Old 07-08-2009, 09:30 PM   #25
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if you still can't figure it out, just kill the main breaker, resetting your clocks ain't that bad...
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Old 07-08-2009, 10:05 PM   #26
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..... it's the induced capacitive electric field the device senses, not magnetic...........
InPhase nailed it and I learned something. He is right about this capacitive coupling thing:

http://support.fluke.com/find-sales/...6001_eng_w.pdf
.

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