Dumb Electrical Question - Wiring (1 Viewer)

[mabrodis]

I do not go near wiring projects without this tool.

Yep, even things that I was sure were wired one way...turns out not...this really old house (1912), with original wiring (as best I could tell...something updated in like 1960, but not everything), glass insulators still in the walls, etc...well had a switch (push button type) for a light...I figure it's just hooked up normal, since why would something that old have any of this new wiring methods (switching the common leg, etc...no idea why I thought that was 'new')....but nope...it was wired to switch the neutral wire...which is annoying since then you really do need to shut off a breaker if at all possible (and with wiring so old when you bent wires the insulation broke off...yeah I wasn't doing this live)..

 

[LandCruiserPhil]

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One common use of white as the "hot" wire in house wiring is the switch leg where a length of 12-2 is the drop. Black is hot into switch and white is hot out of the switch.
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You have it backwards White feeds the switch hot and black is used for the switch leg.

 

[trainrech]

Those "sensors" don't work worth a crap. My less than a year old one was "beeping" that the subpanel in my attic was hot. This would have been fine, but we hadn't pulled the wiring from the basement main panel yet...

 

[mabrodis]

Those "sensors" don't work worth a crap. My less than a year old one was "beeping" that the subpanel in my attic was hot. This would have been fine, but we hadn't pulled the wiring from the basement main panel yet...

They will beep near most metal if close enough to it, and if you move it around it, that's just the nature of them since they want to be very sensitive. So in your case, when you use some thinking you know it can't be hot on the panel, since the panel is never hot...only wires are hot...and you haven't pulled the wires yet...what it actually senses is basically an antenna...since 60-Hz electrical voltage is pulsating through the wire...it's a little antenna that when you get it close enough it can 'hear' the 60-hz cycle and knows that's a hot wire...

In many cases you have to actually pull some wires out, spread them out some to tell what is hot..you can't just put it in a box jammed full of wires and expect it to tell you which one is hot when they all are laying on each other. Or stick it in a dead box, but one that has lots of metal and such in it...it'll usually do some beeping then.

So would you rather have it overly sensitive so it goes off at times when it shouldn't, but using some intelligence you can figure out how to use it correctly....OR....have it not go off because you weren't quite close enough to a wire, or you thought that having it make a noise touching a metal panel is too sensitive, etc...

Meh...I like mine and wouldn't do any electrical work without it...

 

[lumpy70]

OK, I know that there have been a few electricians and handymen in this thread, but for some reason I feel the need to put my two cents in (as an electrician).

1) The code allows a white wire to be hot in residential switching, but it doesn't have to be. The way I learned it was "down (to the switch) on the white, back on black" but it is just arbitrary. Different at every building you're in.

2) Buy a voltage tester. Test, test, and test again. Then, use your pliers to ground it against the box to be sure.

3) The white is sometimes neutral, hot, or both. In the Canadian Code it is simply referred to as the "identified conductor". The color is less relavent than the standard. As someone mentioned, treat everything as hot. In AC, the color simply exists to identify one wire from another.

Craig.