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Good morning,

I had a question about the neutral wire and someone at work explained the neutral as the "return path for the current not used up by the device".

Is this an accurate explanation? I guess I still am having trouble understanding electricity at a fundamental level. I thought any current that left it's source would have to return to complete the circuit. Can someone help me out here as I'm really confused as to what's going on
 

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EE's tell me that the same amount of current is on both legs of the circuit. I don't really see how the load is then taking any power from the pathway, but I also don't understand women and have lived among them for years.:eek:
 

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EE's tell me that the same amount of current is on both legs of the circuit. I don't really see how the load is then taking any power from the pathway, but I also don't understand women and have lived among them for years.:eek:
That's absolutly correct. Once the electrons have passed through the load, they go right back to where they came from. THEN, (get this...) the power company sells those very SAME ELECTRONS back to you, and they've been getting away with this FOR YEARS! Why? Because few people take the TIME to examine their electricity closely.
 

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EE's tell me that the same amount of current is on both legs of the circuit. I don't really see how the load is then taking any power from the pathway, but I also don't understand women and have lived among them for years.:eek:
The load completes the pathway. Without a load there are just dead end wires with no current flowing. Yup, the current is the same on both.
 

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Envision the inside of a single phase service. Say one leg has 40 amps on it, the other might have 20. In theory the neutral would be carrying 20 amps, or the unbalance between the two legs. In the case of 20 amps on both legs, there would be none on the neutral.
 

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EE's tell me that the same amount of current is on both legs of the circuit. I don't really see how the load is then taking any power from the pathway...
Current is never consumed, voltage is always consumed. The load uses power by consuming all the voltage supplied to it and allowing current to flow through it.
 

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Current is never consumed, voltage is always consumed. The load uses power by consuming all the voltage supplied to it and allowing current to flow through it.
I've never heard it explained this way. Its hard to visualize when you're taught voltage is the "pressure" pushing the electrons (current) through the circuit. This makes me think current is what's consumed, which creates work.

I'm a little confused now. I remember in a parallel circuit the voltage drop is the same on each leg but the current changes and is additive (which I assumed is what created "work" in the load) Can you elaborate?
 

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I've never heard it explained this way. Its hard to visualize when you're taught voltage is the "pressure" pushing the electrons (current) through the circuit. This makes me think current is what's consumed, which creates work.

I'm a little confused now. I remember in a parallel circuit the voltage drop is the same on each leg but the current changes and is additive (which I assumed is what created "work" in the load) Can you elaborate?
As everyday electricians who just use the information and summations of those who came before us it is best not to try to go too deeply into the theory any more so than our teachers tell us. Most of the industry is based on theories anyway and if you waste time trying to improve on them you will be just thinking when you SHOULD be working.
 

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RIVETER said:
As everyday electricians who just use the information and summations of those who came before us it is best not to try to go too deeply into the theory any more so than our teachers tell us. Most of the industry is based on theories anyway and if you waste time trying to improve on them you will be just thinking when you SHOULD be working.
Yes, best to go through life not thinking and believe whatever we are told... I agree
 

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It's all about balance.

In a single phase supply, the neutral is a "middle" point in case things are not balanced. For example, one leg has more load than the other.....the neutral will balance the load.

AC is an electromagnetic force that is constantly changing direction. This changing back and fourth is a form of energy by oscillation, like a band saw. This basically means current flows in one direction, then during the half cycle changes back and flows in the opposite direction. So in one full cycle or 1 Hz the current changes directions twice.

Voltage is the actual force that moves the current back and fourth.
 

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Sparky305 said:
I've never heard it explained this way. Its hard to visualize when you're taught voltage is the "pressure" pushing the electrons (current) through the circuit. This makes me think current is what's consumed, which creates work. I'm a little confused now. I remember in a parallel circuit the voltage drop is the same on each leg but the current changes and is additive (which I assumed is what created "work" in the load) Can you elaborate?
Your power bill is based on KWh. What does that tell you? Yes, voltage is electrical pressure, and devices will draw current. It's all about VA or KVA, the total of reactive, inductive and resistive loads. It's all about power!
 

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I've never heard it explained this way. Its hard to visualize when you're taught voltage is the "pressure" pushing the electrons (current) through the circuit. This makes me think current is what's consumed, which creates work.

I'm a little confused now. I remember in a parallel circuit the voltage drop is the same on each leg but the current changes and is additive (which I assumed is what created "work" in the load) Can you elaborate?
Electrical loads utilize energy carried by the circuit and we see it as voltage drop. Remember AC Theory; have a source voltage of 120 volts and wire a resistor to it. Current will remain the same at all points in the circuit but the resistor will drop the 120 volts supplied to it.

Now substitute a light bulb for your abstract resistor and the same thing is going on.

Add more light bulbs in parallel to the first one. Each branch will drop the full voltage applied to it (120 volts) because that's how they consume the power. The current flow seen at the source will increase with each additional parallel load.

Now wire two light identical light bulbs in series; each will only drop 60 volts and only light up half as much. That's why we don't usually wire loads in series with each other.
 

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Current is never consumed, voltage is always consumed. The load uses power by consuming all the voltage supplied to it and allowing current to flow through it.
You've got an interesting POCO then. Out in our part of the country, they charge us for KWH used. So all the POCO uses in your neck of the woods is a volt meter?? Interesting!
 
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