A little electricity 101 if you please

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A couple three basic questions that I'm not willing to test myself.
When pigtailing wires together, you won't get shocked so long as 1) the breaker to that circuit is off 2) you aren't touching both the neutral AND the hot wire. Meaning, if I grab two hot wires and pig-tail them (like when adding in a dimmer) I won't get shocked so long as I'm not touching the neutral wire AND the breaker to that circuit is off. I'm not trying to be ultra safe here so much as I'm trying to make sure that in situation where switching off the breaker isn't a guarentee that power is off for that fixture.
Second question, if I take the probe leads from my volt meter and jam them into an outlet, it's not gonna short the circuit but do exactly what I would expect it to do - read the potential difference between the two sockets in AC volts (assuming your voltmeter is reading AC volts).
And finally, when splicing phone line, do the wires normally carry voltage sufficient to shock or could you essentially splice them with your teeth if you had to?
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The phone lines are safe. You won't feel any shocks.
Power lines are a bit different.There should not be power on the colored power wire, usually black, when the breaker is turned off. Neutrals, the white one, are usually shared by two circuits. In a perfect world there should not be power on the neutrals if everything is wired correctly. DO NOT assume so. You do not tell if your wiring is new enough to have a ground, either green or bare. Turn off the breaker, check between black and white - no power; then use your tester between the black and the green - no power; use your tester between the white and the green - no power, you're good to go.
It is good practice to never use both hands around electricity that can allow current through your heart. If you are not grounded, barefoot, in a puddle of water, or some other grounding you might feel a tingle, but the current can't go through you. I am not suggesting this, but some old electricians might use their finger in a light socket to check for power.
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DanG
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False.
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Doug Miller (alphageek at milmac dot com)
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On Feb 10, 3:01 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

True. It was the practice to have shared neutral circuits, you get two circuits out of 3 wires. The 2 hots were supposed to be hooked up to different busbars, so that the currents in the neutral were out of phase, but over the years, they end up sometimes on the same side. If I can't run an extra wire, I'll hook the two up to a ganged breaker, so that they're on opposite busbars, and on breaker turns both off.
It is relevant here, because when they're on different breakers, throwing one breaker doesn't mean that the neutral isn't hot.
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No, it absolutely is *not* true that "neutrals ... are usually shared by two circuits."
Normal installation is for each circuit to have its own neutral.
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Doug Miller (alphageek at milmac dot com)
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On Feb 11, 1:51 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

Can you define "normal" installation?
The posting followed up to advised the OP that he should watch out for shared-neutral circuits. That is a valid concern, regardless of what you think "normal" installation is.
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I apparently have Spambait plonked, as I don't see his posts, only Nexus replies. Perhaps his responses indicate why I have him blocked.
Residential romex circuits tend to have separate circuit neutrals only because of the nature of the wire. Commercial will nail you to the wall. Very few circuits have their own neutral. In my original reply to the OP, I would rather preach chapter and verse. Always check for a back fed neutral or shared neutral.
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Sorry -- I'll try to make the explanations a little simpler for you.
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Doug Miller (alphageek at milmac dot com)
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As in, the vast majority of residential circuits in the United States.
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Doug Miller (alphageek at milmac dot com)
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Doug Miller wrote:

In Canada, "normal" installation for kitchen counter circuits is to use shared-neutral 15A circuits.
Chris
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Quite so -- but, as I understand it, that's not the norm *except* in kitchens. And it's certainly not the norm in the US, kitchens or otherwise.
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From what I know about neutrals, they ALL are connected together in the panel to a "neutral bar". I would think, therefore, that the neutral has a potential to carry current even though the "hot" on the breaker side is disconnected, just not through that particular "hot" wire. If for some reason the neutrals are not grounded properly, and you happen to be, that could be a problem. Is this not correct? B
wrote:

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You're referring to the situation when the neutrals become somehow disconnected from the neutral busbar, but remain connected to each other. One specific instance of that problem happens in a shared neutral circuit, and is why shared neutral circuits are "bad." However, you're referring to a situation with a fault.
The GP is warning that if the OP's house has shared neutral circuits, the neutral is live, even without any fault, when only the breaker for one side if turned off.
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Personally, I feel that I have better control over my well-being when I use both of my hands when handling live wires and devices. I also try to use my head

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I agree with you totally, but the advice is for someone who is uncomfortable and on new territory. He is not asking how to work something hot.
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I agree with you totally, but the advice is for someone who is uncomfortable and on new territory. He is not asking how to work something hot.
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DanG
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Outstanding idea.
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Doug Miller (alphageek at milmac dot com)
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When in doubt... Throw the main

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