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Discussion Starter #1
I have a house built in 1868.

So it had gas, knob and tube and every other kind of lighting.
Most of the house just has two copper wires in a fabric casing. The other half is new. But you can bet its all mixed in.

If changed out a couple of plugs and fixtures.
Some of the time I work with hot wires.

anyway.
I've noticed that when I touch one of the wires I get a little voltage, regardless of flipping the braker or not. A little tingly feeling.

What the heck is causing that?
 

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What the heck is causing that?
electricity flowing through at least part of your body.


with what you describe, it could be many things. Bad connections (highly resistive) could cause you to become the ground source (neutral) and then current flows through you. Circuits can have shared neutrals (1 A leg and 1 B leg when correct). Some folks share a lot more than that. In old wiring systems, the sometimes used only 1 neutral for the whole house and tapped into it.

Many things could be going on. Just be damned careful. It really doesn;t take much to kill you so if you are gettiing a tingle, you could be getting dead real soon.
 

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I have a house built in 1868.

So it had gas, knob and tube and every other kind of lighting.
Most of the house just has two copper wires in a fabric casing. The other half is new. But you can bet its all mixed in.

If changed out a couple of plugs and fixtures.
Some of the time I work with hot wires.

anyway.
I've noticed that when I touch one of the wires I get a little voltage, regardless of flipping the braker or not. A little tingly feeling.

What the heck is causing that?
The first problem is that you are grabbing wires looking for a tingle:no:! Stop it! You may just be grabbing a shared neutral that is split between the circuit you are working on and another live circuit. Grabbing it may let you become a high resistance path in the circuit, since some current flows through all parallel paths.
 

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Knob & Tube? IMO, get rid of it immediately!
It should be a law that it be replaced by all, and low cost loans should be offered to help pay for it.
It's a lot cheaper to replace it now, than to replace the house, or worse after a fire!

Just my opinion. Take it or leave it.
 

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Have you insulated? You CANNOT insulate with knob and tube.

Anyways, its probably a shared neutral (multiwire circuit)

You need to get a multi meter from radio shack for like $20.
 

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I would advise you to turn off the "main power" to the house before doing any work in the future. Then you will be sure everything is off.

And have an electrician check the grounding on your main electric panel.
 

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Discussion Starter #8
well, to be honest
I do work on live circuts once and a while.
Get a major shock about once every two years.
Tools go flying along with curse words!
 

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well, to be honest
I do work on live circuts once and a while.
Get a major shock about once every two years.
Tools go flying along with curse words!

Ive gotten shocked before...I know how it feels, but it wasn't when I was working on a circuit...it was a device I made.

You NEED to stop doing that, you could die.
 

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I've been shocked 120v house wiring though my hand before. It wasn't terrible, but 120v still gives you a nice stiff shock on dry skin.

Basically I had turned off the breaker... well, a breaker. It wasn't the right one apparently even though I was very sure. I was 16 years old at the time so I guess my standards weren't so high for working safely. Not as bad as my 25 year old friend that trusted a 16 year old to wire new outlets for him though. :p

I've taken 300v from a photoflash arm to arm. That was a pretty stiff kick in the chest. It literally felt like getting punched in the chest.

The worst was probably 190 VDC B+ voltage inside a CRT. There are some CRT adjustments you have to perform live, and some manufacturers put helpful "testing posts" sticking out of the PCB with live voltage on them. Thanks guys. hehe Anyway the B+ voltage I got arm-to-leg... The next day I was sore like I had exercized too much. DC power really strains your muscles. They don't vibrate like with 60hz, they just contract.
 

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I should mention, the difference between a tingle and a stiff shock is just a little sweat on your skin. The difference from a stiff shock and death might be a scratch that breaks the skin. It's not something to take unnecessary risks with.
 

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I've taken 300v from a photoflash arm to arm. That was a pretty stiff kick in the chest. It literally felt like getting punched in the chest.
That 300v from the photoflash was just a charged capacitor. Not all that much energy (coulombs) compared to a live wire.
I took one from a cap that was charged to about 3KV once, but it was a small cap, and was across the fingers. It definitely woke me up!
Also, DC tends to throw you back, while AC tends to cause you to hold on tighter. But from what I have read, there is a range from around 100V to 500VAC that is most dangerous. Higher than that, apparently will cause burns, but doesn't cause the muscles to contract and grasp.

In any case, working on live wires isn't something you want to make a practice.
 

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That 300v from the photoflash was just a charged capacitor. Not all that much energy (coulombs) compared to a live wire.
No, but a photoflash is still 7 joules. Defibrillator is 150-300 joules for comparison. Photoflash probably won't stop your heart, but it's still a kick in the chest.
 

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I've been shocked 120v house wiring though my hand before. It wasn't terrible, but 120v still gives you a nice stiff shock on dry skin.

Basically I had turned off the breaker... well, a breaker. It wasn't the right one apparently even though I was very sure. I was 16 years old at the time so I guess my standards weren't so high for working safely. Not as bad as my 25 year old friend that trusted a 16 year old to wire new outlets for him though. :p

I've taken 300v from a photoflash arm to arm. That was a pretty stiff kick in the chest. It literally felt like getting punched in the chest.

The worst was probably 190 VDC B+ voltage inside a CRT. There are some CRT adjustments you have to perform live, and some manufacturers put helpful "testing posts" sticking out of the PCB with live voltage on them. Thanks guys. hehe Anyway the B+ voltage I got arm-to-leg... The next day I was sore like I had exercized too much. DC power really strains your muscles. They don't vibrate like with 60hz, they just contract.

I had a photoflash with about 10 caps hooked up. That was my "device". My arms didn't feel too good for awhile.
 
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