Is a shock worse from the neutral

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tom baker

tom baker

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I had a first aid class recently where the instructor mentioned "shock from the neutral". alluding to its worse than a shock from the hot conductor.
I have heard this before, what basis would there be for this belief?
 
tom baker said:
... I have heard this before, what basis would there be for this belief?
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My first unasked questions are:
  1. Under what conditins can one get shocked from a neutral?
  2. Is this anecdotal information - as in you have tried it?
  3. Is there any way to measure this?

But this is a first aid instructor - he doesn't know. So, next questions:
This must be coming from a paper. Do you have a reference? - cause I don't know of any physics that would cause this phenomea.

Bet you a cup of yuppie coffee the answer is, That's what they told us in our instructors' class.

You: So this is in your instructors' class book?

Instructor: No

Just thinking, not saying dfinitely:
To get a shock from a neutral, the neutral would have to be open circuited. So one's body is in series with the load - Hot to load, load to body, body to current return (probably grounding/bonding connections) The current flow through one's body is likely very low , so little voltage drop across the load - most VD is across the body path. Inductive load driving up voltage? I'm not seeing the model -

So, without a paper on the physics model: Color me clueless

ice
 
One possible factor (and that is stretching to try to find a reasonable meaning for that statement) is that when you get a shock from a hot wire you are usually making an accidental contact and are likely to jerk or be thrown away, breaking the connection.
To get a "shock from the neutral" (whatever that really means) you must be dealing with an interrupted neutral connection, such as from a cut wire or a cut pipe which had been carrying current from an already failed neutral. That suggests to me that you are going to be working with the ends of the pipe or wire and are probably solidly gripping both ends, making it more likely that you will stay in the circuit longer and suffer more injury.
 
ptonsparky said:
Absolutely none. Maybe even less. At least with the neutral, you would have a resistance in the circuit, instead of just your body to limit the current flow.
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I had that happen to me last week. Bootleg neutral from another panel caused me to get bit. It wasn't the worst shock I ever had but it made me madder since I had done my due diligence with my meter before I started in.
 
GoldDigger said:
One possible factor (and that is stretching to try to find a reasonable meaning for that statement) is that when you get a shock from a hot wire you are usually making an accidental contact and are likely to jerk or be thrown away, breaking the connection.
To get a "shock from the neutral" (whatever that really means) you must be dealing with an interrupted neutral connection, such as from a cut wire or a cut pipe which had been carrying current from an already failed neutral. That suggests to me that you are going to be working with the ends of the pipe or wire and are probably solidly gripping both ends, making it more likely that you will stay in the circuit longer and suffer more injury.
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That is exactly what I thought when I read this. You complete the circuit nod it is likely to do more damage then normal shock from the hot. Of course completing the circuit on the hot would be just s bad.
 
ptonsparky said:
Absolutely none. Maybe even less. At least with the neutral, you would have a resistance in the circuit, instead of just your body to limit the current flow.
Click to expand...

I agree, if you got hit off of a ballast neutral that had a 1/4 amp load then that would be the maximum current of you and the ballast in series.
 
tom baker said:
I had a first aid class recently where the instructor mentioned "shock from the neutral". alluding to its worse than a shock from the hot conductor.
I have heard this before, what basis would there be for this belief?
Click to expand...


I think he may have meant that it is unexpected. That is why it is worse or it seems to hurt more because you are not expecting to get shocked from a neutral.
 
I have heard the same thing, too. There was no substantiation other than anecdotes.

One explanation I was given that if there is a capacitor on the circuit and the neutral is open, a person could have the capacitor discharge through them. I have never witnessed such a thing, though.
 
K8MHZ said:
I have heard the same thing, too. There was no substantiation other than anecdotes.

One explanation I was given that if there is a capacitor on the circuit and the neutral is open, a person could have the capacitor discharge through them. I have never witnessed such a thing, though.
Click to expand...

And if there is a capacitor on the circuit and the hot wire and neutral are both connected the capacitor could discharge through you too. That explanation does not make much sense to me either.
 
The worst shock I ever got was from a neutral. It was because I was in series with the load.

One may be more cautious about getting between two ungrounded conductors. With the hot shocks I experienced it was line to ground so I was in series with a relatively high impedance. I never recall getting in series with a load on the ungrounded conductor.

There would be little difference between being in series with a load on a ungrounded conductor vs. being in series with a load on the grounded conductor but I would think the neutral case would be more common.

Being in series with the load (a shock from the neutral) would hurt more than a touch voltage scenario with an ungrounded because of the difference in impedance.

I would think that is where the notion of a neutral shock being worse comes from.
 
mivey said:
The worst shock I ever got was from a neutral. It was because I was in series with the load. ...

... Being in series with the load (a shock from the neutral) would hurt more than a touch voltage scenario with an ungrounded because of the difference in impedance. ....
Click to expand...

Huh ?? That makes no sense to me at all. Maybe you could draw this one out and educate me a bit.

ice
 
iceworm said:
Huh ?? That makes no sense to me at all. Maybe you could draw this one out and educate me a bit.

ice
Click to expand...

Code: 
[FONT=Courier New]
H-----------------------|
                        |
                        |
                      Load
                        |
                        |
                        |
G                       |
|                       |
|                       |
|                       |
N-------mivey-----------|


H----------|------------|
           |            |
          mivey         |
           |          Load
           |            |
          Zhigh         |
           |            |
G----------|            |
|                       |
|                       |
|                       |
N-----------------------|
[/FONT]
 
edward said:
I think he may have meant that it is unexpected. That is why it is worse or it seems to hurt more because you are not expecting to get shocked from a neutral.
Click to expand...

I could see an instructor thinking that. But to me, saying you were shocked by a white or gray wire is different than saying you were shocked by the neutral. I guess to be shocked by the neutral your body could have been brought to a higher potential by some line or fault and a circuit was completed when a grounded conductor is touched.

When I was an apprentice, I heard the 277V neutral wire was the neutral that could shock you and the 120V neutral was harmless. I suppose that is a combination of wisdom coming from being shocked by an open neutral and the ferocious hit of 277V. I know how it works, now. These days, when I hear someone talking about being shocked by a neutral, it throws up a red flag as to their credibility (no disrespect to mivey, please. I understand your meaning.)

I still avoid touching complete circuit neutral conductors because of fear of a latent open neutral connection even in panels where I can see the (system) bonding jumper.
 
I think most of this comes from multi-wire circuits that someone opens to add another conductor to and don't expect to be hit so they are less cautious and make a better connection, also an unexpected hit also seems allot more then it really is as the mind can play tricks on us, one case that proved this was when you apply your brakes on ice you will think your speeding up when your really just not slowing down as fast as your mind is expecting.

But opening a neutral to an inductive/capacitive load can and in some cases will produce an inductive kick that can be up to 4kv's it doesn't have much current behind it but it still hurts, even an inductive kick at 12 volts can hit you hard as I found out changing out a battery in a car with the engine still running and my bare belly was against the fender while I was pulling off one of the cables, dropped me to my knees, didn't have any jumper cables so I put my battery in the other persons car but left my engine running encase I ran down the battery while trying to get the other car started, wouldn't try this with a newer car but back in the late 60's to early 70's it wasn't a problem.
 
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