# The mysterious neutral



## Big John (May 23, 2010)

Voltage is always consumed by the resistance of the circuit. If you plug a toaster in, most of the voltage is consumed by the resistance of the toaster coils. There is a tiny little bit of resistance on the wires leading up to the toaster, and a little bit leading away, but the voltage drop on those is small.

Current is never consumed. In a series circuit the current measured at the beginning is the exact same amount as the current in the end, no matter how much resistance it goes through. 

So the current on the hot may be the same as the current on the neutral, but by the time that current gets to the neutral bus, there's very little voltage behind it, because most voltage has already been consumed by the load. That's why you can touch the neutral bus without getting shocked.

If you open the neutral, there's no current flow anymore, so there's no load being driven and no voltage can be consumed. That means the full voltage is present on the neutral, which is how you can get a dangerous shock.


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## polyphase (Nov 1, 2011)

The neutral is groinded, what u got to always remeber is that electricity takes the less pass of resistants, now if u break a neutral and your body is between the 2 wire than yes u will get bit your the path then. I've touched live bus/lugs in panels (but don't do it), but I wasn't grounded so I was ok. ALWAYS think about what your doing when working in a live panel.


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## HackWork (Oct 2, 2009)

You are touching the other side of the neutral.

The neutral bar in the panel is bonded to ground which means there is 0 potential to ground and you can't get shocked.

You get shocked when you "open" a neutral and touch the side coming from the circuit. The electricity is going thru the load and looking to get back to the source thru the neutral. When you touch the neutral while also being grounded, you are completing the path.


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## ohmontherange (May 7, 2008)

If you create a parallel path of the same resistance the cuurrent will divide equally. If you create a parallel path of greater resistance... well, do the math.


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## Sparky305 (Feb 7, 2012)

Big John said:


> So the current on the hot may be the same as the current on the neutral, but by the time that current gets to the neutral bus, there's very little voltage behind it, because most voltage has already been consumed by the load. That's why you can touch the neutral bus without getting shocked.
> 
> If you open the neutral, there's no current flow anymore, so there's no load being driven and no voltage can be consumed. That means the full voltage is present on the neutral, which is how you can get a dangerous shock.


I still don't get it. Correct me if I'm wrong, current is the actual electrons moving through the wire. The voltage is what pushes it through, but it's the current that hits you. If there's still current flowing through the neutral bus, although with 0 volts, wouldn't you still get hurt since it's the current that does the damage?


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## butcher733 (Aug 4, 2012)

polyphase said:


> I've touched live bus/lugs in panels



Have you met Charles Darwin?:laughing:


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## Sparky305 (Feb 7, 2012)

HackWork said:


> You are touching the other side of the neutral.
> 
> The neutral bar in the panel is bonded to ground which means there is 0 potential to ground and you can't get shocked.


Well this is where my confusion lies. I understand its bonded to ground and at 0 volts, but there is still current flowing through it going back to the source. I think the current should still be able to hit you when you touch the neutral bus


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## someonespecial (Aug 31, 2012)

Sparky305 said:


> I still don't get it. Correct me if I'm wrong, current is the actual electrons moving through the wire. The voltage is what pushes it through, but it's the current that hits you. If there's still current flowing through the neutral bus, although with 0 volts, wouldn't you still get hurt since it's the current that does the damage?



No, your skin has something like 20K of resistance to it so with so little voltage, nothing happens. 

It's the same reason you can touch the + and - of a 800A car battery and nothing will happen to you - it's only 12v.


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## micromind (Aug 11, 2007)

You can get shocked only if there's a difference in voltage between one part of your body and another. Current has nothing to do with it. 

When you touch the neutral bar in a panel, your finger and every other part of your body are at the same voltage regardless of the current anywhere in the system, because the neutral bar is grounded. 

When you open a neutral splice and touch any neutral that has a load on it and any part of your body is grounded, there is voltage between the now ungrounded neutral wire and whatever part of you is grounded. POW!

If the impedance of the load is high enough, the voltage will appear across the load, not your body. But just about every electrical load has a much lower impedance that a human body.


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## Big John (May 23, 2010)

Sparky305 said:


> ...The voltage is what pushes it through, but it's the current that hits you...


 Right, but there are two parts to getting shocked:

First, you need to have enough current to hurt, and all that takes is about 0.004 amps. That is such a small amount of current, that practically _everything _can supply enough current to hurt you: A science-fair lemon powered clock can supply that much current.

Second, you need enough voltage to push it through, like you said. The only thing that keeps batteries and lemon-clocks and such from painfully shocking us is that lack of voltage. The same way the neutral bus doesn't have enough voltage to shock you, either.


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## kalexv12 (Apr 23, 2009)

Sparky305 said:


> Well this is where my confusion lies. I understand its bonded to ground and at 0 volts, but there is still current flowing through it going back to the source. I think the current should still be able to hit you when you touch the neutral bus


Only if you were to make yourself a better path to ground maybe by standing barefoot in a concrete basement where the service ground/neutral is poor


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## RIVETER (Sep 26, 2009)

Sparky305 said:


> We all know that you can get a shock from the neutral wire. If I open any neutral splice and theres a load connected, and I touch it, I'm gonna get hit.
> 
> My question is, why/how is it possible to touch the neutral bus bar in the panel and not get shocked? I understand that the neutral is at the same potential as ground, but if theres still current coming back on those wires, going into the bus, and back to the transformer, the source, shouldn't I get shocked when touching the bus? This has me really confused :icon_confused:


It is confusing. You have to remember that the neutral does not have to be grounded in order for a device to work. Therefore, the way a person may get "bit" is that they possibly get themselves in series with a load. They then become part of the load. You are right in saying that the neutral is at the same potential as ground but you have to remember that that is only because we connect the two together. GROUND is not necesssary for a system to work properly.


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## papaotis (Jun 8, 2013)

RIVETER said:


> It is confusing. You have to remember that the neutral does not have to be grounded in order for a device to work. Therefore, the way a person may get "bit" is that they possibly get themselves in series with a load. They then become part of the load. You are right in saying that the neutral is at the same potential as ground but you have to remember that that is only because we connect the two together. GROUND is not necesssary for a system to work properly.


 correct me if im wrong, please, but isnt the nuetral grounded? somewhere:whistling2:


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## RIVETER (Sep 26, 2009)

papaotis said:


> correct me if im wrong, please, but isnt the nuetral grounded? somewhere:whistling2:


Not unless you connect it to ground.


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## papaotis (Jun 8, 2013)

i believe the nuetral from the poco is 'grounded', in some locals at every ut pole


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## RIVETER (Sep 26, 2009)

papaotis said:


> i believe the nuetral from the poco is 'grounded', in some locals at every ut pole


You're most probably right, but do you understand that the neutral does not have to be at ground potential to do it's job?


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## papaotis (Jun 8, 2013)

10-4 got it ! not tryin to argue just making it clear, whwich you helped with:thumbup:


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## Sparky305 (Feb 7, 2012)

Thanks for all the replies, this actually makes sense now!


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## hardworkingstiff (Jan 22, 2007)

papaotis said:


> correct me if im wrong, please, but isnt the nuetral grounded? somewhere:whistling2:


Yes, the neutral is grounded all along the PoCo distribution system, and at your service disconnect (which is often the main breaker panel on the structure). 

So, one reason you don't get shocked if you are grounded and touch the neutral bar in the panel is because it is referenced to ground very close to where you are standing. Remember, if you are not referenced to ground (or to an ungrounded phase) you will not get shocked if you touch the neutral or any of the phases in the panel.

Someone said that electricity takes the path of least resistance. Well, that is actually not 100% correct, the correct statement is electricity takes all paths of possible current flow. Keeping this principle in mind, if you are in a junction box that has current flowing on the circuit, and you are well grounded, you can get a shock by touching the neutral wire without opening the neutral circuit. How (since the neutral is referenced to ground) is this possible? Well, the way that happens is there is a voltage drop on the neutral wire going back to the panel and you are now a parallel current path, and if your path for current has a low enough resistance and the VD is high enough, you can feel the current. If you should break the neutral of a live circuit carrying current, and touch the load side neutral conductor and you are grounded, you become the only path for current and you are in a series circuit. You will feel this one, and it will startle you and possibly hurt you.

These are principles of electricity that every electrical worker should strive to understand. I commend the members that ask about this and learn, it could save a life one day, maybe even yours.


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## brian john (Mar 11, 2007)

polyphase said:


> The neutral is grounded, what u got to always remember is that electricity *takes the less pass of resistance* now if you break a neutral and your body is between the 2 wire than yes u will get bit your the path then. I've touched live bus/lugs in panels (but don't do it), but I wasn't grounded so I was ok. ALWAYS think about what your doing when working in a live panel


*Not true*- Electricity will take all available conductive paths.

As for touching a neutral at the panel, touch a phase conductor and the neutral if you want to get shocked. The potential is there.


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## papaotis (Jun 8, 2013)

a B.I once told me, electricity is nstupid, it doesnt always take the path its supposed to!


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## Aegis (Mar 18, 2011)

Big John said:


> Voltage is always consumed by the resistance of the circuit. If you plug a toaster in, most of the voltage is consumed by the resistance of the toaster coils. There is a tiny little bit of resistance on the wires leading up to the toaster, and a little bit leading away, but the voltage drop on those is small.
> 
> Current is never consumed. In a series circuit the current measured at the beginning is the exact same amount as the current in the end, no matter how much resistance it goes through.
> 
> ...


I'm thinking there IS voltage on the neutral. When we test the closed neutral to ground we get zero volts, because the ground and neutral are connected back at the source as everyone else here has said. That's like putting both of your leads of your meter on the same hot wire, we get zero because there's no potential.


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## 8V71 (Dec 23, 2011)

Aegis said:


> I'm thinking there IS voltage on the neutral.


 
????? voltage with reference to what?


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## brian john (Mar 11, 2007)

8V71 said:


> ????? voltage with reference to what?


 
To the phase conductor Yes.

The ground conductor yes, depending on voltage drop in the neutral conductor which is as always dependent on distance to the load, size of the conductor and current on the conductor.


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## hardworkingstiff (Jan 22, 2007)

Aegis said:


> I'm thinking there IS voltage on the neutral. When we test the closed neutral to ground we get zero volts, because the ground and neutral are connected back at the source as everyone else here has said. That's like putting both of your leads of your meter on the same hot wire, we get zero because there's no potential.


But, the farther you get away from that neutral/ground connection, the more voltage drop will increase the amount of voltage you can read from neutral to ground (at the load). Of course, no current, no VD. So, this is really a dynamic condition and neutrals need to be treated cautiously.


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## FastFokker (Sep 18, 2012)

8V71 said:


> ????? voltage with reference to what?


Exactly.

Voltage isn't anything, it's only the difference of potential between two reference points.

Also, it's common trade vernacular to refer to the return wire on a 2-wire system as the neutral, but it's technically not. It's the return or load side of the hot conductor. A real neutral only exists in a multi wire polyphase circuit and is only neutral when the load is balanced. Otherwise it will have voltage to ground and have current going through it.


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## 220/221 (Sep 25, 2007)

I'm sure it has been said but, the simple explanation is: the *current will take the path of least resistance.*

Copper/aluminum is a far better conductor than the human body.


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## hardworkingstiff (Jan 22, 2007)

220/221 said:


> I'm sure it has been said but, the simple explanation is: the *current will take the path of least resistance.*
> 
> Copper/aluminum is a far better conductor than the human body.


Psst, current takes "all" paths, just more of it goes through lower resistance, but it takes all paths not all of it on the lowest resistance path.


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## brian john (Mar 11, 2007)

There is nothing mysterious about electricity, some folks may not know a lot about the subject, some may know a little and some a lot, but to my knowledge all mysteries have been solved.


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## hardworkingstiff (Jan 22, 2007)

brian john said:


> .. but to my knowledge all mysteries have been solved.


Except ground up/down. :laughing:


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## 220/221 (Sep 25, 2007)

hardworkingstiff said:


> Psst, current takes "all" paths, just more of it goes through lower resistance, but it takes all paths not all of it on the lowest resistance path.


 I think you know what I/we mean. 

You can technically say that just about any statement about anthing is wrong but, for the purpose of explaining to the rookie, in his thread, it's the easiest to understand.

We all know that current doesn't flow like water but, it kind of gets the point across in the 101 class.



> Not true- Electricity will take all available conductive paths.


If you put your voltmeter leads on feeder lug and a branch circuit terminal lug of a loaded neutral bus, how much will flow thru your meter?


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## brian john (Mar 11, 2007)

220/221 said:


> I think you know what I/we mean.
> 
> You can technically say that just about any statement about anthing is wrong but, for the purpose of explaining to the rookie, in his thread, it's the easiest to understand.


But it is WRONG and propogates false statements and then the helper/apprentices goes around not knowing the truth about his chosen profession.

Get it right the first time


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## hardworkingstiff (Jan 22, 2007)

220/221 said:


> I think you know what I/we mean.
> 
> You can technically say that just about any statement about anthing is wrong but, for the purpose of explaining to the rookie, in his thread, it's the easiest to understand.
> 
> We all know that current doesn't flow like water but, it kind of gets the point across in the 101 class.


 Yea, I was always told I should not be a teacher.


> If you put your voltmeter leads on feeder lug and a branch circuit terminal lug of a loaded neutral bus, how much will flow thru your meter?


As much as the VD will drive through the meter.


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## Big John (May 23, 2010)

Aegis said:


> I'm thinking there IS voltage on the neutral....


 I agree. But it's a very small amount based on the voltage drop of the conductor, and most people won't feel it.

I've done repair calls where people were getting shocked by bootleg neutrals, though. The two I can think of: One could only be felt when you were standing barefoot on a concrete floor, and the other one was when you touched a metal appliance and the sink with wet hands.


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## 220/221 (Sep 25, 2007)

brian john said:


> But it is WRONG and propogates false statements and then the helper/apprentices goes around not knowing the truth about his chosen profession.
> 
> Get it right the first time



But, how much current will flow thru the meter? 

If current is taking the path thru the meter, shouldn't it register?

I'm not being a smart ass, more of a dumb ass because I honestly don't know.


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## brian john (Mar 11, 2007)

220/221 said:


> But, how much current will flow thru the meter?
> 
> If current is taking the path thru the meter, shouldn't it register?
> 
> I'm not being a smart ass, more of a dumb ass because I honestly don't know.


Neither do I but I was not discussing a meter.

With a 8 digit multimeter I am sure we could find out, or if we know the impednace of the meter but that is Big John's job


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## hardworkingstiff (Jan 22, 2007)

220/221 said:


> But, how much current will flow thru the meter?
> 
> If current is taking the path thru the meter, shouldn't it register?
> 
> I'm not being a smart ass, more of a dumb ass because I honestly don't know.


So little you probably can't measure it because the resistance between the 2 points you chose is almost zero. The resistance of the meter is so high that I doubt you can measure the current flow in this instance. 

But, just because an example can be shown in which the neutral won't hurt you dose not mean all neutrals are in this condition.


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## papaotis (Jun 8, 2013)

lick your finger, touch the nuetral bar. stick your tongue to anything else in that box, how much voltage is there?:laughing: sorry, ive had a bad day


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## ScooterMcGavin (Jan 24, 2011)

220/221 said:


> But, how much current will flow thru the meter?
> 
> If current is taking the path thru the meter, shouldn't it register?
> 
> I'm not being a smart ass, more of a dumb ass because I honestly don't know.


On a quality digital multi meter the impedance will be 1 Mega Ohm or greater. You don't want a voltage meter to draw any current it should only register the voltage potential between the points you are measuring. Mainly because it could effect sensitive electronic or control circuits by adding a burden to the circuit. Knopp testers and wiggies are generally down in the 10 kilo ohm range so the will draw a small amount of current because the solenoid is a load on the circuit.


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