Is a shock worse from the neutral

[iceworm]

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


H----------|------------|
           |            |
          mivey         |
           |          Load
           |            |
          Zhigh         |
           |            |
G----------|            |
|                       |
|                       |
|                       |
N-----------------------|
[/FONT]

... 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.) ....

Well, you drew out exactly what I expected. There is no physics leaping off the paper explaining why A could give any worse shock than B.

Jeremy -
If you understnd - perhaps you could explain it.

Just a thought:
I am defining a worse shock as more current passing through one's body parts. As is a 10ma shock is worse than a 5 ma shock.

ice

 

[kwired]

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


H----------|------------|
           |            |
          mivey         |
           |          Load
           |            |
          Zhigh         |
           |            |
G----------|            |
|                       |
|                       |
|                       |
N-----------------------|
[/FONT]

I'm failing to see what "Zhigh" is. I get that it means high impedance, but what is there that has high impedance? If anything in the situation where you are in series with the load the load impedance could be limiting the voltage drop across "mivey" and the higher the impedance the less current will flow through the entire circuit. When connected without the load in series "mivey" should be the only impedance in the circuit.

 

[kwired]

Just a thought:
I am defining a worse shock as more current passing through one's body parts. As is a 10ma shock is worse than a 5 ma shock.

ice

And exactly what body parts the current flows through could be a factor in what is a "worse shock", as well as differences between individuals subjected to same conditions. My hands are probably higher resistance in general then a banker or doctor's hands. Add an open wound in my hand and it may be less at that point in time though.

 

[iceworm]

I'm failing to see what "Zhigh" is. ...

My guess: Zhigh = Z(mivey) >> Z(load)

ice

 

[kwired]

My guess: Zhigh = Z(mivey) >> Z(load)

ice

OK, but unless you have a pretty weak source in which the voltage is significantly reduced because of the (load), (mivey) is still applied across full (near full) output voltage of the source and (load) has little to no impact on how much current flows through (mivey).

 

[iceworm]

OK, but unless you have a pretty weak source in which the voltage is significantly reduced because of the (load), (mivey) is still applied across full (near full) output voltage of the source and (load) has little to no impact on how much current flows through (mivey).

Precisely

ice

 

[iwire]

What is the PF of one Mivey? Will I need to add capacitors to keep my electric bill down?

 

[iceworm]

What is the PF of one Mivey? Will I need to add capacitors to keep my electric bill down?

Remember, most all of my experience is industrial.

Generally speaking, AOL mivey installations burn clear fairly quickly

(Paraphrase of a chief engineer comment concerning reclosers)

 

[iwire]

Generally speaking, AOL mivey installations burn clear fairly quickly

Ouch, that will leave a mark.

 

[Besoeker]

To get a shock from a neutral, the neutral would have to be open circuited.........

And it would have to that side of the break no longer connected to neutral. And thus not at neutral potential.
Debatable whether the shock can be really be called a shock from the neutral...
Nah, no debatable about it. It isn't a shock from the neutral.

 

[GoldDigger]

How about a shock from "the wire formerly known as neutral"?

 

[Besoeker]

How about a shock from "the wire formerly known as neutral"?

Sorta works.....

 

[mivey]

Well, you drew out exactly what I expected. There is no physics leaping off the paper explaining why A could give any worse shock than B.

I assumed you would consider contact resistance without me having to spell it out.

I'm failing to see what "Zhigh" is. I get that it means high impedance, but what is there that has high impedance? If anything in the situation where you are in series with the load the load impedance could be limiting the voltage drop across "mivey" and the higher the impedance the less current will flow through the entire circuit. When connected without the load in series "mivey" should be the only impedance in the circuit.

It is not only the body resistance but the contact resistance. Reaching in a box and completing the circuit across two ends of a neutral is worse, at least in my experience, than incidental contact with a line conductor where the circuit is completed through clothes, minimal contact area & pressure, wet shoes, earth, A/C ductwork, nearby piping etc. where the net impedance outside the body is relatively high.

I have never reached across two line conductors. I did have a co-worker brush a service drop neutral with his shoulder while holding 277 volts and he fell off a ladder from the reaction. Had he grabbed the two open neutral ends he probably would have been bit much harder: simple physics.

For what I'm calling a neutral shock, the load may be a couple hundred ohms in series with "mivey". For me brushing a line conductor while kneeling, standing, lightly touching a nearby grounded object, etc. "mivey" will be in series with hundreds and maybe even thousands of more ohms. The load ohms would be small as compared to the contact + ground return impedance.

YMMV

 

[mivey]

My guess: Zhigh = Z(mivey) >> Z(load)

ice

No. Zhigh is high contact + ground return impedance. Z(mivey) was present in both cases but in the neutral case the contact resistance is also much lower because it was an intentional contact (me grabbing the neutral wires to bring them together).

 

[mivey]

What is the PF of one Mivey? Will I need to add capacitors to keep my electric bill down?

Your electric bill will be very small because mivey is going to let go and you will have an open circuit for most of the billing cycle.

 

[mivey]

And it would have to that side of the break no longer connected to neutral. And thus not at neutral potential.
Debatable whether the shock can be really be called a shock from the neutral...
Nah, no debatable about it. It isn't a shock from the neutral.

It is not a matter of what it should technically be called. Tom asked for the basis for this belief and these beliefs are not so doctrinaire in nature.

 

[iceworm]

I,,,It is not only the body resistance but the contact resistance.

...For what I'm calling a neutral shock, the load may be a couple hundred ohms in series with "mivey". For me brushing a line conductor while kneeling, standing, lightly touching a nearby grounded object, etc. "mivey" will be in series with hundreds and maybe even thousands of more ohms. The load ohms would be small as compared to the contact + ground return impedance.

No. Zhigh is high contact + ground return impedance. Z(mivey) was present in both cases but in the neutral case the contact resistance is also much lower because it was an intentional contact (me grabbing the neutral wires to bring them together).

Just checking my translation:
A "neutral shock" is worse because the connection is a low contact resistance because one has firmly grabbed it.

A line to ground shock is not as bad because the contact resistance is high because the contact is incidental brushing.

Would this be correct?

 

[Besoeker]

It is not a matter of what it should technically be called. Tom asked for the basis for this belief and these beliefs are not so doctrinaire in nature.

Fairy 'nuff.
But suggesting that shock from a neutral is worse is just plain wrong.
The potential on it, even if broken and you still call the broken part neutral regardless of disputed validity, still comes from a live.
To claim that a shock can be worse is just absolute nonsense.
IMHO.

 

[ptonsparky]

With this line of reasoning the shock I received from an EG would be even worse than the Neutral. We were chasing a known fault when I managed to series myself in the path. I vote for it. Only one worse was the 277.

 

[kwired]

Reaching in a box and completing the circuit across two ends of a neutral is worse, at least in my experience, than incidental contact with a line conductor where the circuit is completed through clothes, minimal contact area & pressure, wet shoes, earth, A/C ductwork, nearby piping etc. where the net impedance outside the body is relatively high.

Something worth consideration there. But that is different from contacting an ungrounded conductor vs. the open netural conductor and other same point of contact. Example contacting a 120 volt ungrounded conductor and the EGC compared to open energized neutral and same EGC. Both instances you will experience about same shock - maybe some difference with a really high impedance load in series with the neutral.