Grounded box + line = shock

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Old 03-28-17, 03:43 PM
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Exclamation Grounded box + line = shock

I just want to start off by saying that I have a professional coming out for another reason soon, so I will have him take a look at this, but I am real curious as to what might be going on here as it will be a few days before that happens.

I was changing a light switch and did not turn off the breaker. It's dumb, I know, and you are free to tell me that it's / I'm dumb. I've done it numerous times, and very rarely ever get shocked, and when I do, I know why: I hit two wires. This time, however, I got shocked by brushing the line while touching the ground wire. The box is metal, so, being the genius that I am, I touched the box and then the line to double check, and... another shock, which at least means that the box is grounded (which I could have told myself by seeing the ground attached to it).

Why would touching the ground and line cause a shock, or, would it always do that/this is normal and I've just never hit them both before? 120V, 15A line, USA. Thanks.
 
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Old 03-28-17, 03:52 PM
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Welcome to the forums! You got shocked once and went back for seconds, knowing it would happen??

The ground is a direct path back to the grounding bar in the panel. Touching it and a live wire will give you the same results time after time. Just chalk it up to experience and make sure you always remove the power from a circuit before you work on it.
 
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Old 03-28-17, 04:07 PM
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You can get a shock anytime there is a difference of potential between two things. You body completed the path between hot and ground so you got a shock.
 
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Old 03-28-17, 04:26 PM
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you are free to tell me that it's / I'm dumb. I've done it numerous times
You're dumb but you're probably not the first person to figure out touching hot wires is bad.
Don't ask me how I found out what a red wire was for
 
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Old 03-28-17, 04:37 PM
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Why would touching the ground and line cause a shock
To answer your question directly.... ground and neutral are connected to the same exact place in the panel. They are both at ground potential.
 
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Old 03-28-17, 04:45 PM
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Much appreciated, thank you all. Glad to know this is normal.
 
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Old 03-28-17, 04:53 PM
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Just FYI : It is much more common for people to get a shock between hot to ground because metal parts are often grounded. To receive a shock from hot to hot or hot to neutral will require you to be touching two wires at the same time. It does happen, just not as much.

This is why one needs to be very careful when working on 277 volts in commercial installations. It is 277 volts to ground.
 
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Old 03-28-17, 05:01 PM
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This is why one needs to be very careful when working on 277 volts in commercial installations. It is 277 volts to ground.
This specific issues comes up all too often when working on commercial lighting fixtures while ones body is in direct contact to the grounded metal grid ceiling.
 
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Old 03-28-17, 06:16 PM
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grounded metal grid ceiling
Grounded metal trusses, steel framing, ductwork, ceiling wires, MC/AC cable, everything is grounded!
 
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Old 03-28-17, 08:00 PM
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You got shocked once and went back for seconds, knowing it would happen??
..... And people wonder why we need warning labels on everything......
 
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Old 03-29-17, 01:04 AM
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In Canada 347 volts is a common commercial lighting voltage. More than one electrician or apprentice has unfortunately been killed trying to change a fluorescent ballast live. If the shock didn't get them, the fall off the scaffold did.

Regards,
Brian
 
 

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