you don't get shocked if you touch only the hot screw on outlet?

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electrofelon said:
I'm not following the "intentional ground" concept. If you are grounded, and touch the hot conductor, you are going to get hit whether or not the neutral is connected. The connection status of the neutral will not affect anything. What it does do is provide a big grounded object right where you are working so I cut that first and tie it out of my way
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Okay. Thank you for the grace of time. Here's my thinking.

Real World Example

Have you ever walked up to a metal case and received a shock when you grabbed the door handle? I sure have, so I touch metal cases with the back of my hand even today before I reach for the door handle. If you ever experienced this event, why did you get shocked? The short answer, for some reason, you were a better ground (neutral) than the intentional ground of the circuit.
 

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LadyDi said:
Okay. Thank you for the grace of time. Here's my thinking.

Real World Example

Have you ever walked up to a metal case and received a shock when you grabbed the door handle? I sure have, so I touch metal cases with the back of my hand even today before I reach for the door handle. If you ever experienced this event, why did you get shocked? The short answer, for some reason, you were a better ground (neutral) than the intentional ground of the circuit.
Click to expand...
I am somewhat confused by your terminology. I still am not completely clear on what you mean by "intentional ground". Because you are calling ground, intentional ground, and neutral all the same thing,. I believe you are using these terms to refer to one "side" of a circuit or the "return" path that completes a circuit. Similar to how we refer to the negative side of an automobile electrical system as ground. Is that correct? May I ask what industry you are involved in? Just curious because of the terminology seems like you're maybe in a different industry than premise wiring.

I also find the example in your attachment mostly irrelevant because it is referring to series circuits which essentially do not exist in premise wiring. In the attachment, yes I agree placing a jumper over one of the resistors would make the potential between those points essentially zero, but that doesn't really make any sense anyway because you can't just jumper one of the resistors with resistors in series as you will increase the voltage drop across and current thru of the other resistors.

Okay, I think what you are saying is one can get shocked by touching an open neutral (where there are loads connected between it and the ungrounded conductor of course) and a return path to the source. Yes of course that happens, I acknowledged it previously and said in the case of the four square box that if you break the neutral first and then the hot you are dealing with two live connections, where if you break the hot first you are only dealing with one live connection. But even if you break the neutral first, the potential of the ungrounded conductor to ground is still what it is and does not change (sorry if that is not what you are saying, seems like it was).

For my service drop example do you see how breaking the neutral first and moving it out of the way is safer? Note I am assuming we have access to the service disconnect or pull the meter so we know there are no loads connected making the neutral energized.

In summary, to be blunt, your "break the neutral last, make the neutral first". Philosophy is not always true. It depends on the situation. You can't make a blanket statement that that is always safer.
 
LadyDi said:
Have you ever walked up to a metal case and received a shock when you grabbed the door handle? I sure have, so I touch metal cases with the back of my hand even today before I reach for the door handle. If you ever experienced this event, why did you get shocked? The short answer, for some reason, you were a better ground (neutral) than the intentional ground of the circuit.
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Are you talking about a static shock, or continuous current?
 
Hv&Lv said:
277 was my worst hit ever.
😂😂 It’s funny now but your right! Hand in a vice!

I swear I hurt for a couple of days and was scared for a year…
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120 if solid connection will hurt for days too. And tachycardia. Hand to elbow on ceiling grid. A simple slip of the conductors while working to make connection was all it took. NEVER will work "live" again. Or I will glove up.
All these people I've been exposed to that said "It's only 120 no need to shut it down.", are full of .....
electrofelon said:
For my service drop example do you see how breaking the neutral first and moving it out of the way is safer? Note I am assuming we have access to the service disconnect or pull the meter so we know there are no loads connected making the neutral energized.

In summary, to be blunt, your "break the neutral last, make the neutral first". Philosophy is not always true. It depends on the situation. You can't make a blanket statement that that is always safer.
Click to expand...
You glove up when make/break the service drop connection?
 
LadyDi said:
Have you ever walked up to a metal case and received a shock when you grabbed the door handle? I sure have, so I touch metal cases with the back of my hand even today before I reach for the door handle. If you ever experienced this event, why did you get shocked? The short answer, for some reason, you were a better ground (neutral) than the intentional ground of the circuit.
Click to expand...
Got minor jolt from metal door knob on a trailer. Found the metal siding of trailer to literal earth metered 120V. Door knob had about 30V.
 
electrofelon said:
I am somewhat confused by your terminology. I still am not completely clear on what you mean by "intentional ground". Because you are calling ground, intentional ground, and neutral all the same thing,. I believe you are using these terms to refer to one "side" of a circuit or the "return" path that completes a circuit. Similar to how we refer to the negative side of an automobile electrical system as ground. Is that correct? May I ask what industry you are involved in? Just curious because of the terminology seems like you're maybe in a different industry than premise wiring.

I also find the example in your attachment mostly irrelevant because it is referring to series circuits which essentially do not exist in premise wiring. In the attachment, yes I agree placing a jumper over one of the resistors would make the potential between those points essentially zero, but that doesn't really make any sense anyway because you can't just jumper one of the resistors with resistors in series as you will increase the voltage drop across and current thru of the other resistors.

Okay, I think what you are saying is one can get shocked by touching an open neutral (where there are loads connected between it and the ungrounded conductor of course) and a return path to the source. Yes of course that happens, I acknowledged it previously and said in the case of the four square box that if you break the neutral first and then the hot you are dealing with two live connections, where if you break the hot first you are only dealing with one live connection. But even if you break the neutral first, the potential of the ungrounded conductor to ground is still what it is and does not change (sorry if that is not what you are saying, seems like it was).

For my service drop example do you see how breaking the neutral first and moving it out of the way is safer? Note I am assuming we have access to the service disconnect or pull the meter so we know there are no loads connected making the neutral energized.

In summary, to be blunt, your "break the neutral last, make the neutral first". Philosophy is not always true. It depends on the situation. You can't make a blanket statement that that is always safer.
Click to expand...
I work in the electrical field. Perhaps our terminology is different because of location. Let's say we are dealing with a single-phase 120-volt circuit. I think we agree that it takes two conductors to get this circuit to work: (1) an ungrounded conductor (hot) and (2) a grounded conductor. Do you consider that ungrounded conductor a neutral? Please refer to the NEC Article 100 terms. Using Ohms Law, would you show me why the concept does not apply to parallel circuits? I am willing to consider at your thinking.
 
Fred B said:
Got minor jolt from metal door knob on a trailer. Found the metal siding of trailer to literal earth metered 120V. Door knob had about 30V.
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Yikes!
 
LadyDi said:
A continuous current.
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Ah, this adds context. Now to respond to:
LadyDi said:
Have you ever walked up to a metal case and received a shock when you grabbed the door handle? I sure have, so I touch metal cases with the back of my hand even today before I reach for the door handle. If you ever experienced this event, why did you get shocked? The short answer, for some reason, you were a better ground (neutral) than the intentional ground of the circuit.
Click to expand...
Not necessarily a better ground (pathway), merely an additional one, in parallel with any others. Not only will a new, lower-impedance pathway conduct current inversely proportionate to its impedance, any existing parallel pathway already there will continue to carry the current it already was . . .

. . . unless that new pathway has a low-enough impedance that it conducts enough current to operate the OCPD supplying it. That is the exact purpose of the EGC: to force the OCPD to open as if a line-to-neutral (grounded conductor) fault had occurred.

And, of course, the EGC-to-neutral bond is an essential part of that low-impedance pathway. It cares not one whit whether the earth is involved, only that the EGC pathway is so much a better conductor than people that it shuts down the power, forcing the cause to be found and corrected.

A common misconception is that current seeks (only) the pathway of lowest resistance. Granted, that pathway will conduct the most current but certainly not all of it. If it did, then only the largest load at any given moment would operate on a circuit or service.

So, the "reason" the shocked person was shocked was because the EGC pathway was either non-existent or of too much impedance to open the OCPD. The shock itself was a result of that deficiency. The person was not a better current pathway, just an unfortunate additional one.
 
Fred B said:
Got minor jolt from metal door knob on a trailer. Found the metal siding of trailer to literal earth metered 120V. Door knob had about 30V.
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Two short stories:

A friend of mine bought a used travel trailer that was handyman wired with 120V shore power through a suicide cord. When he brought in a cable TV connection he accidentally touched the connector to an aluminum window frame, which arced and melted the spot on the frame where the cable made contact. Whoever wired the trailer had got hot and neutral reversed, and he bonded what he thought was neutral to the frame of the trailer.

A rent house I lived in had (for some reason) an aluminum framed window in the shower. My wife and I learned very quickly not to touch the window frame while we were standing ankle deep in water in the shower, else we would get shocked. I measured 120V from the window frame to the tub spigot.
 
electrofelon said:
I'm not following the "intentional ground" concept. If you are grounded, and touch the hot conductor, you are going to get hit whether or not the neutral is connected. The connection status of the neutral will not affect anything. What it does do is provide a big grounded object right where you are working so I cut that first and tie it out of my way
Click to expand...
There is a difference between disconnecting a grounded conductor and disconnecting a conductor that has a downstream grounding connection.

With typical utility service drop the incoming conductor is already grounded, often the outgoing conductor is as well. So your risk of shock is about same whether you connect it first or last.

Now a more limited system like an automobile electrical system, you usually should disconnect the negative (bonded to frame) first and connect it last when connecting to the source, but that source doesn't already have a reference to the frame like a utility source already has a ground reference.

A reason I would make up the neutral last on a service drop is because of close quarters between conductors and metallic crimping tools. make up the ungrounded first, and insulate them as you make them up, so that there is nothing at high potential for the tool to contact when making up the neutral that is bare. Done this maybe more on farm places with overhead distribution between poles and buildings than on a individual service drop at a dwelling. If you make the neutral up first you have that bare conductor near where you are crimping an ungrounded conductor and more risk of contacting it with the tool. Shock potential isn't really the reason for connecting the grounded conductor last here, that risk is similar either way you do it.
 
LadyDi said:
I work in the electrical field. Perhaps our terminology is different because of location. Let's say we are dealing with a single-phase 120-volt circuit. I think we agree that it takes two conductors to get this circuit to work: (1) an ungrounded conductor (hot) and (2) a grounded conductor. Do you consider that ungrounded conductor a neutral? Please refer to the NEC Article 100 terms. Using Ohms Law, would you show me why the concept does not apply to parallel circuits? I am willing to consider at your thinking.
Click to expand...
Also consider that because of voltage drop, a grounded conductor carrying current will have a rise in volts over "earth". Often times not enough to be noticeable by simple touching, but anytime there is current there is a voltage drop across the conductor. With a MGN utility supply even an unloaded grounded service conductor still will typically have some small voltage to earth because of voltage drop on the primary neutral it is also bonded to.
 
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