Why is the neutral called the grounded conductor?

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teufelhounden91 said:
All right fellow wizards, I just had another discussion with the boss man and he said that current does not need to travel back to the same source but current can find another "source" to travel to and as long as there is a difference of potential, current will still flow. He said that the earth has such a high resistance value and it has such a different potential than the source voltage at a utility that current will still flow and you could still light a lightbulb in between a hot from the utility and the other side of the potential (the earth). He said current flow has nothing to do with getting back to the original source neutral. As long as you have a difference of potential and a high enough resistance value current will flow. His example was if you are at a light pole that is near a utility transmission line, and you get and induced voltage on that pole that you can take a wire from the pole go over to the break caliper on the car with rubber tires and no contact with earth, it will allow current flow. In this instance you have no reference through the earth back to source neutral so how is this possible? His next impossible situation was that if we have a hot wire coming from the utility and we can touch it to a building that is completely insulated from the earth with a massive piece of rubber he still thinks current will flow because of the resistance value of that building. He said if there's a high enough resistance in the entirety of that building, it will be an opposite polarity for electricity to discharge to.... Regardless of earth. He also said that a guy standing in an insulated bucket was recently shocked near transmission line current flowed through the air from the line to him and he got shocked with no referenced through the ground back up to source. How is this possible if current has to leave source and return to source to flow?


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That sounds more like different paths then different source. Source is just that, the transformer, battery or generator. The one that's driving the electromotive force.
 
teufelhounden91 said:
All right fellow wizards, I just had another discussion with the boss man and he said that current does not need to travel back to the same source but current can find another "source" to travel to and as long as there is a difference of potential, current will still flow. He said that the earth has such a high resistance value and it has such a different potential than the source voltage at a utility that current will still flow and you could still light a lightbulb in between a hot from the utility and the other side of the potential (the earth). He said current flow has nothing to do with getting back to the original source neutral. As long as you have a difference of potential and a high enough resistance value current will flow. His example was if you are at a light pole that is near a utility transmission line, and you get and induced voltage on that pole that you can take a wire from the pole go over to the break caliper on the car with rubber tires and no contact with earth, it will allow current flow. In this instance you have no reference through the earth back to source neutral so how is this possible? His next impossible situation was that if we have a hot wire coming from the utility and we can touch it to a building that is completely insulated from the earth with a massive piece of rubber he still thinks current will flow because of the resistance value of that building. He said if there's a high enough resistance in the entirety of that building, it will be an opposite polarity for electricity to discharge to.... Regardless of earth. He also said that a guy standing in an insulated bucket was recently shocked near transmission line current flowed through the air from the line to him and he got shocked with no referenced through the ground back up to source. How is this possible if current has to leave source and return to source to flow?

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This gets far more complicated. There are those here who can really dazzle you with science and math. To keep it more simple though, what you boss says is marginally or perhaps potentially (pun intended) correct. Difference in potential is actually what causes current flow, period. Voltage is a difference in potential. BUT... the energy available is the huge factor here. When you rub on carpet and touch a door knob, current flows. And the potential is huge, sometimes a thousand or more volts. Again take a closed loop water system. If you opened a leak, which would be similar to the "car situation" you describe, the water would flow, but only until there was not enough water at the source to maintain that flow. In the case of electricity, this is a speed of light thing. Utility companies have to be very careful with disconnected transformers and capacitors, because they will build up potential over time and "store" it. When a person becomes the conductor between the potentials they can get a big enough jolt to die. Once the potential levels back out. The current flow becomes a trickle.

Not quite sure about the exact situation of the guy in the insulated bucket, but you are not getting the whole story. Either the current left the source and returned to the source, regardless of whether this was due to capacitive or inductive coupling or a direct path, or the source wasn't what you describe. As in, the source was something like a transformer I described earlier. And then the flow, was still coupled with the source. Electrons aren't magic. They don't just exist and cease to exist. They are real, whether they are particles or waves, which is still disputed I believe. Just like the water example, they can't continue to flow unless they are replenished. In terms of electricity, that replenishment is current flowing form the source ot the load and back to the source, period. Even if that is through the core of the earth, magnetism, etc.
 
I just tested this theory under a specific condition. I just bought two brand-new 9 V batteries. I connected the positive lead of one battery to the negative lead of a different battery with a piece of wire. I put my amp clamp on it and there was no current flow. Then I connected the positive lead to the negative lead of the same battery and voilà...current flow. Now essentially as my boss is saying the earth has a massive resistance, so I took the battery and connected a lead from the battery down to the earth. No current flow. However when I took another piece of wire from the ground back to the other battery lead completing the circuit… current flow.


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teufelhounden91 said:
I just tested this theory under a specific condition. I just bought two brand-new 9 V batteries. I connected the positive lead of one battery to the negative lead of a different battery with a piece of wire. I put my amp clamp on it and there was no current flow. Then I connected the positive lead to the negative lead of the same battery and voilà...current flow. Now essentially as my boss is saying the earth has a massive resistance, so I took the battery and connected a lead from the battery down to the earth. No current flow. However when I took another piece of wire from the ground back to the other battery lead completing the circuit… current flow.


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Not quite sure of the point you are making or understanding exactly what you did. Your words however, contradict what your master E told you as you stated, "completing the circuit" which is giving the electrons a path back to the source.
 
Why is the neutral called the grounded conductor?

This proves to me, at least in the DC circuit, current will not flow if you have a different source. It has to go back to the same source. Now I do believe that in the case of the battery it's the difference of potential through the dielectric medium that is creating the current flow so if you separate the batteries there's no more dielectric in between the anode and cathode so there's no way current can flow. But isn't this the same situation that were talking about in an AC system where current has to leave source and come back to source? Guess when I get home I'm going to have to test this out with the lightbulb and a piece of wire coming off my panel. I also have a motor at home that I'm gonna hook up as if it were a generator and manually spin the Armature to test this theory instead of using batteries and only DC voltage. The problem I find though as there are so many ground rods and water pipes bonded in my neighborhood that I'm always going to have some sort of reference back to utility neutral. So how do I get around this?


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teufelhounden91 said:
This proves to me, at least in the DC circuit, current will not flow if you have a different source. It has to go back to the same source. Now I do believe that in the case of the battery it's the difference of potential through the dielectric medium that is creating the current flow so if you separate the batteries there's no more dielectric in between the anode and cathode so there's no way current can flow. But isn't this the same situation that were talking about in an AC system where current has to leave source and come back to source? Guess when I get home I'm going to have to test this out with the lightbulb and a piece of wire coming off my panel. I also have a motor at home that I'm gonna hook up as if it were a generator and manually spin the Armature to test this theory instead of using batteries and only DC voltage. The problem I find though as there are so many ground rods and water pipes bonded in my neighborhood that I'm always going to have some sort of reference back to utility neutral. So how do I get around this?


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I don't really think you have to Prove this out at home. You already proved it. Higher voltage just means that you have a better potential of jumping across or breaking down the insulator. If you need to confirm in your own mind that AC acts the same way as DC in this circumstance, then just use a portable generator, isolate it from the ground just to be sure.
 
Strathead said:
Not quite sure of the point you are making or understanding exactly what you did. Your words however, contradict what your master E told you as you stated, "completing the circuit" which is giving the electrons a path back to the source.
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Well my boss said that as long as there's a difference potential current will flow. He said the source does not matter for current to flow. His idea that the earth is an opposite polarity then a transformer up on the pole and that is why current will flow to ground. He said that the neutral on the pole in the ground are both equal things so current will travel and seek either one because they are both essentially "negative" He does not believe that current travels back through the earth up to the source where it was derived. So essentially he saying that if a fault happens current will seek any path to a different potential, not a path back to source.

So my experiment shows with two different sources that current will not flow unless it's able to seek out it's own source from where it came from. The first battery is the source, the second battery would be a separately derived source. If his theory is right since I found a neutral of another source that there's also a difference of potential between the first batteries negative in the second battery is positive – current should still flow. My argument is that is incorrect because current is going to seek its home, where it came from, or it will not flow period.


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When you are dealing with AC, capacitive coupling is just as capable of carrying current back to s source as a resistive connection would be. You just have to calculate the current glow based on all of the series impedances. Most often the capacitive reactance will be the dominant value in limiting the current. But if the applied voltage is high enough the resulting current can still be dangerous.

There will be a calculable capacitance between any two objects on earth or in space, but it is usually small enough that we can ignore it. For DC, as with a battery, we can always ignore it in the steady state calculation.
 
Strathead said:
I don't really think you have to Prove this out at home. You already proved it. Higher voltage just means that you have a better potential of jumping across or breaking down the insulator. If you need to confirm in your own mind that AC acts the same way as DC in this circumstance, then just use a portable generator, isolate it from the ground just to be sure.
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I agree with you. In theory AC and DC operate the same way fundamentally. I should not have to replicate this experiment, however I'm going to do so to be thorough.

He also said that if you have a large semi truck with a generator on it and no reference to a ground rod or a GEC at the truck you Will still get shocked from the casing of the generator to earth if you're standing barefoot while touching the generator. Even though the truck is sitting on rubber tires. I don't believe this is possible because if current leaves the casing of the generator, travels through you took earth, there has to be away from earth to it to get back up into the generator for current to flow, but he said he's seen it happen before. I somehow feel as though I'm not getting the full story.


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GoldDigger said:
When you are dealing with AC, capacitive coupling is just as capable of carrying current back to s source as a resistive connection would be. You just have to calculate the current glow based on all of the series impedances. Most often the capacitive reactance will be the dominant value in limiting the current. But if the applied voltage is high enough the resulting current can still be dangerous.

There will be a calculable capacitance between any two objects on earth or in space, but it is usually small enough that we can ignore it. For DC, as with a battery, we can always ignore it in the steady state calculation.
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Master Jedi, I'm trying to follow you lol are you talking about capacitive coupling through the air on transmission lines and still being able to complete a circuit? Sorry I'm trying to understand how capacitive coupling enters the situation that we are talking about.


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If the generator on the truck does not have any earth connection, you can still have current flowing through your barefooted test subject if wires connected to the generator have sufficient capacitive coupling to earth.
If no wires leave the truck to go to (ungrounded) loads, there should not be any current worth worrying about.
 
teufelhounden91 said:
Well my boss said that as long as there's a difference potential current will flow. He said the source does not matter for current to flow. His idea that the earth is an opposite polarity then a transformer up on the pole and that is why current will flow to ground. He said that the neutral on the pole in the ground are both equal things so current will travel and seek either one because they are both essentially "negative" He does not believe that current travels back through the earth up to the source where it was derived. So essentially he saying that if a fault happens current will seek any path to a different potential, not a path back to source.

So my experiment shows with two different sources that current will not flow unless it's able to seek out it's own source from where it came from. The first battery is the source, the second battery would be a separately derived source. If his theory is right since I found a neutral of another source that there's also a difference of potential between the first batteries negative in the second battery is positive – current should still flow. My argument is that is incorrect because current is going to seek its home, where it came from, or it will not flow period.


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I don't know if there is a confusion in semantics with your boss, or he is just trying to confuse you. Let me try to go back to the basics.

Voltage is a difference in potential. This would be equivalent to two tanks of water connected with a hose that have different pressure, or different height for example.
Zero volts is a reference point not an absolute value, in other words, it is only zero volts in reference to the other point you are measuring.
Any time there is a difference in voltage that is great enough to overcome a resistance between them current will flow. It will flow as long as the voltage is great enough to overcome that resistance. Period. Simple as that, end of story.
If I had an internal charge of 1000 volts in reference to say, the ground rod in my house, but I also had a 500 volt charge in reference to the door know on my wooden door. I reached out and touch the door, I would get a static zap. This is current flow, but at the speed of light, the door know and I would now have a 0 volt difference. The charge would still remain 1000 volts to the ground rod though.

And, by the way, your last sentence. You apparently didn't hook up a voltmeter to your two batteries, because there isn't a difference in potential between them unless it is a "static' type difference as described above. You should read zero volts between the two batteries, no matter which terminals you read between.

Do realize though, that everything we talk about has a but... When we want to start getting technical, we can talk about insignificant flows, over time, dirt, humidity causing flow, and any of thousand of other variables. But the bottom line is current flow is from a source through a load and back to the source.
 
GoldDigger said:
If the generator on the truck does not have any earth connection, you can still have current flowing through your barefooted test subject if wires connected to the generator have sufficient capacitive coupling to earth.
If no wires leave the truck to go to (ungrounded) loads, there should not be any current worth worrying about.
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Since the subject of static electricity has been introduced, I want to round out the discussion by noting that when you acquire a static charge you are in fact charging a capacitor.
The charging process is a complete circuit when you count the virtual current that is represented by the changing electric field between the plates of the capacitor.
When you discharge that capacitor you again have a complete circuit from one plate of the capacitor to the other plate and the virtual current as the electric field between the plates goes back to zero.
 
GoldDigger said:
Since the subject of static electricity has been introduced, I want to round out the discussion by noting that when you acquire a static charge you are in fact charging a capacitor.
The charging process is a complete circuit when you count the virtual current that is represented by the changing electric field between the plates of the capacitor.
When you discharge that capacitor you again have a complete circuit from one plate of the capacitor to the other plate and the virtual current as the electric field between the plates goes back to zero.
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Do you understand what Golddiggger is saying here teufl? If not, basically a capacitor in his example is used as a battery. It takes a electrical energy to charge it storing the energy and then when demanded it discharges it.
 
Strathead said:
I don't know if there is a confusion in semantics with your boss, or he is just trying to confuse you. Let me try to go back to the basics.

Voltage is a difference in potential. This would be equivalent to two tanks of water connected with a hose that have different pressure, or different height for example.
Zero volts is a reference point not an absolute value, in other words, it is only zero volts in reference to the other point you are measuring.
Any time there is a difference in voltage that is great enough to overcome a resistance between them current will flow. It will flow as long as the voltage is great enough to overcome that resistance. Period. Simple as that, end of story.
If I had an internal charge of 1000 volts in reference to say, the ground rod in my house, but I also had a 500 volt charge in reference to the door know on my wooden door. I reached out and touch the door, I would get a static zap. This is current flow, but at the speed of light, the door know and I would now have a 0 volt difference. The charge would still remain 1000 volts to the ground rod though.
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I hear you, but why is there a difference of potential to the ground rod? Is it because the earth has a different potential than the xfmr or is it because there is an available path back through the earth to the xfmr the current was generated at? (Neutral) I'm having trouble understanding why my boss says the neutral on the pole and the planet earth are the same thing and that if you remove the neutral all together, current will flow to earth because it's another different potential, not because there's a path to get back to the xfmr where it was created. Will current flow to ANY difference of potential or will it only flow back to source? He said the current seeks planet earth if source cannot be found, because it's the next best potential that can be found. Is this right?

And, by the way, your last sentence. You apparently didn't hook up a voltmeter to your two batteries, because there isn't a difference in potential between them unless it is a "static' type difference as described above. You should read zero volts between the two batteries, no matter which terminals you read between.
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I did, and you're right there's no potential between the batteries. I always thought the dissimilar metals naturally had a potential between them inside a battery, but I guess the dielectric inside allows the potential to exist? Man I'm confused now. Thanks for sticking with me on this. I'm a visual learner so maybe I'm struggling because I can't see it in my head.

Do realize though, that everything we talk about has a but... When we want to start getting technical, we can talk about insignificant flows, over time, dirt, humidity causing flow, and any of thousand of other variables. But the bottom line is current flow is from a source through a load and back to the source.
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When you say that I hear "current ONLY flows from source back to SAME source." I definitely added words there but in my mind that's where all of this confusion lies. My boss says no...current can leave one potential (xfmr) and travel to any other potential it chooses (earth) and there's a complete circuit happening.


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Strathead said:
Do you understand what Golddiggger is saying here teufl? If not, basically a capacitor in his example is used as a battery. It takes a electrical energy to charge it storing the energy and then when demanded it discharges it.
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I think I understand how a capacitor works in a DC circuit. I understand what he saying, there's essentially a build up of a difference of potential, and when it discharges it's equalizing so there's no longer a difference. What I do not understand is how that forms a complete circuit. When the discharge occurs, are you saying that is when the circuit is completed?

The term capacitive coupling throws me off I think. I've heard people use the term magnetic coupling when talking about transformers and I understand that, but I do not understand what is meant by capacitive coupling. Do you have a diagram that may help me understand this? Still having trouble wrapping my head around inductive reactance and capacitive reactance. What makes the charge decide to discharge itself?


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Maybe I should not go into this, but I cannot resist. Looking at Maxwell's equations describing Electricity and Magnetism, we find that a changing electric field in empty space will generate a magnetic field in the same way that an actual motion of electric charges does.
If you consider this changing electric field to be a virtual current, you find that the changing electric field between the plates of a capacitor as you charge it is exactly equal to the current of real charges flowing between the plates in the external circuit.
So, in that sense you do have a complete circuit with equal current flowing at all points in the circuit, including the empty space between the plates of the capacitor.
Isn't physics wonderful?

PS: The capacitor tries to discharge itself because the difference in voltage between its terminals (and the corresponding electric field) exerts a force on the electrons that tries to accelerate them into motion.
 
GoldDigger said:
Maybe I should not go into this, but I cannot resist. Looking at Maxwell's equations describing Electricity and Magnetism, we find that a changing electric field in empty space will generate a magnetic field in the same way that an actual motion of electric charges does.
If you consider this changing electric field to be a virtual current, you find that the changing electric field between the plates of a capacitor as you charge it is exactly equal to the current of real charges flowing between the plates in the external circuit.
So, in that sense you do have a complete circuit with equal current flowing at all points in the circuit, including the empty space between the plates of the capacitor.
Isn't physics wonderful?

PS: The capacitor tries to discharge itself because the difference in voltage between its terminals (and the corresponding electric field) exerts a force on the electrons that tries to accelerate them into motion.
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Ok, that makes sense now.


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