I have explained several times, attaching a scope to a center tap will make that scope lie to you. I gave you the example of ANY delta. You corrected me that you can buy a scope with a floating common. OK put that on L1 and tell me what you see.
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and you will see this
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How many phases do you see? I only see one. Is there any angle shift in that secondary? I don't see any. A generator would act the same way. Your "2 supply" thing is just an illusion caused by looking at a system from the middle. I understand people have come up with all sorts of things to try to rationalize what they see with their meter or a scope but it is really pretty simple if you understand power systems.
I still wonder why you persist with your paralleling bullshit. Draw that out and you will see you are simply connecting L1 to L2 and you don't need to do anything with the white wire at all. You can leave it disconnect on both circuits and you still get a bolted fault.
So there is another point of semantic confusion in this discussion.
120/240 can mean 120 Volts and 240 Volts can refer to the two voltages in a usual home system.
0/120/240 can also refer to 0 degrees , 120 degrees , 240 degrees, the three phase angles in the usual 3 phase system.
? apart, the current would have to be flowing from L1 towards L2 AND from L2 towards L1 at the same instant.
You can't answer the simple questions a student would ask a teacher in circuits 101, yet I'm the one who's supposed to be stupid? I give you a simple example, where I morph the old 90 deg two phase into exactly what 240/120 service is and you won't answer the questions. Instead you divert to transformers, when there is no transformer. Now you've gone further down the rabbit hole, declaring that you can't analyze simple electrical circuits unless that circuit exists in the real world.
Here are the simple questions again:
Problem two:
According to Fretwell, two phase power existed 100 years ago, and it was over two wires, 90 degrees phase difference. Suppose I run it over 3 wires instead, with a shared neutral, make it 120V. So, you have a generator supplying 120V, two coils, one shared neutral. Would there still be two phases there? (I believe Fretwell said yes) Your answer?
So now, I run that from the generator into a house, we have three wires,
120V, two phases. If I change the phase difference to 179 degrees instead of 90 by rotating one coil, are there still two phases? Yes or no?
Now I rotate it to 180 phase difference. Are there still two phases, yes or no? If you disagree, explain how it's different, how there suddenly there are not two phases there.
(My answer is yes and the final step above makes it absolutely IDENTICAL to what you have coming into the house with 240/120. The electrons are behaving exactly the same. )
Problem number 3
I take 3 phase power with a neutral into a house. One phase is at zero, one is at 120, one is at 240, correct? I can see them on a scope, yes?
Now I rotate one coil so that instead of 120, it's at 179. Are there still three phases?
Now I rotate it one degree more, to 180. Are there still 3 phases, yes or no?
Now take away the 240 phase. How many phases now? If it's not two, explain why.
And if it is two, then again, it's now ELECTRICALLY IDENTICAL TO 240/120 se rvice. IF you believe it's electrically different, explain why and how it matters in terms of the behavior of the electrons in the service conductors.
Problem number 4:
Draw the basic circuit model of 240/120 service. My model uses TWO voltage sources, with a shared neutral. One is 120V sin(wt), the other 120V sin(wt+180) or of alternate polarity connection, if you like. That is the only way to model that circuit, because that is what is there. When you center tap it, you now have TWO voltage sources. Which by the way is exactly what the professor is saying, you have two sources, 180 out of phase with each other, that's how you treat it. Do you agree with that? If not, tell us your alternate model .
Scopes don't lie. And it's not some parlor trick point that you connect the scope to. It's the SYSTEM neutral/reference point. And of course when you do that, you see TWO 120V voltage sources, one 180 deg out of phase from the other. It's the essence of why the system was created that way. I've asked many times now, if you disagree that there are in fact two 120V voltage sources, coming from the two halves of the secondary, to draw your simple circuit model that shows it fifferently. I've given you the two voltage source model. The IEEE Fellow, elec engineering professor gave the same model. This is very basic, first day of circuits
101 stuff.
I gave you the example of ANY delta.
Show us how you model and analyze that circuit going into the house without TWO 120V voltage sources, one 180 out of phase with the other with respect to the neutral or of opposite polarity, same thing. And you'd have exactly the same thing if you took a two phase 90 deg generator and rotated one winding to 180. Which of course is why you bail out and won't answer those simple questions and instead start talking about transformers.
Yes, it is. You have two 120V voltage sources going into the house, one 180 deg out of phase from the other. Look up the definition of phase.
Because one can parallel any two conductors that are in phase and of the same voltage, that's why. Can you parallel the two 120V hots you see in the house?
I don't think there has been any confusion over references to phase or voltage in this discussion if you read the context in which they are being used. I will keep it in mind though.
Here are the two simple problems that no one on the other side can address and it isn't because there is any confusion about voltage vs phase. It's because they are trapped in a obvious unexplainable contradiction.
Problem two:
According to Fretwell, two phase power existed 100 years ago, and it was over two wires, 90 degrees phase difference. Suppose I run it over 3 wires instead, with a shared neutral, make it 120V. So, you have a generator supplying 120V, two coils, one shared neutral. Would there still be two phases there? (I believe Fretwell said yes) Your answer?
So now, I run that from the generator into a house, we have three wires,
120V, two phases. If I change the phase difference to 179 degrees instead of 90 by rotating one coil, are there still two phases? Yes or no?
Now I rotate it to 180 phase difference. Are there still two phases, yes or no? If you disagree, explain how it's different, how there suddenly there are not two phases there.
(My answer is yes and the final step above makes it absolutely IDENTICAL to what you have coming into the house with 240/120. The electrons are behaving exactly the same. )
Problem number 3
I take 3 phase power with a neutral into a house. One phase is at zero, one is at 120, one is at 240, correct? I can see them on a scope, yes?
Now I rotate one coil so that instead of 120, it's at 179. Are there still three phases?
Now I rotate it one degree more, to 180. Are there still 3 phases, yes or no?
Now take away the 240 phase. How many phases now? If it's not two, explain why.
And if it is two, then again, it's now ELECTRICALLY IDENTICAL TO 240/120 service. IF you believe it's electrically different, explain why and how it matters in terms of the behavior of the electrons in the service conductors.
trader, you keep saying that we get 240v by combining 2 120v phases that are 180 degrees apart. That's utter nonsense!
The 240v is derived from one continuous secondary winding. You'll note that the neutral tap is not even used for 240v. And since it is single phase on the transformer primary, it is single phase on the transformer secondary.
Sure, you can add a tap long the secondary winding and get a reduced voltage but it is still single phase.
In the context of electrical distribution phase refers to the angular displacement between the wave on the conductors and there is no angular displacement in a straight line, only one end and the other end. bisecting a line does not make 2 lines unless one changes direction (angular displacement)
It's not utter nonsense. Do you deny that the circuit is two 120v secondaries that are tied together? How do you draw the simple circuit diagram, using ideal voltage source that represent what you have there? I draw it with two 120V voltage sources, with one 180 deg out of phase with the other with respect to the neutral, or of opposite polarity, same thing. The IEEE Fellow, power engineer, professor, says exactly the same thing. If you disagree, show us the circuit model that doesn't us e two 120V voltage sources. And where those sources come from, two halves of the secondary, or two windings from a generator, or electronically synthesized from a batter, doesn't matter. In all cases they are 120V voltage sources and the power into the house looks, acts and is the same.
You get two voltage sources that are 180 deg out of phase or of opposite polarity with respect to the tap, that's what you get. And the "tap" is the SYSTEM neutral! It's the reference for your power delivery. It's not some random, accidental, inconsequential point.
Ready to answer the very simple questions? Fretwell can't, he gets part way through and then suddenly starts talking about transformers, when there are no transformers in any of the simple problems.
Problem 1:
Define N phase power?
Problem two:
According to Fretwell, two phase power existed 100 years ago, and it was over two wires, 90 degrees phase difference. Suppose I run it over 3 wires instead, with a shared neutral, make it 120V. So, you have a generator supplying 120V, two coils, one shared neutral. Would there still be two phases there? (I believe Fretwell said yes) Your answer?
So now, I run that from the generator into a house, we have three wires,
120V, two phases. If I change the phase difference to 179 degrees instead of 90 by rotating one coil, are there still two phases? Yes or no?
Now I rotate it to 180 phase difference. Are there still two phases, yes or no? If you disagree, explain how it's different, how there suddenly there are not two phases there.
(My answer is yes and the final step above makes it absolutely IDENTICAL to what you have coming into the house with 240/120. The electrons are behaving exactly the same. )
Problem number 3
I take 3 phase power with a neutral into a house. One phase is at zero, one is at 120, one is at 240, correct? I can see them on a scope, yes?
Now I rotate one coil so that instead of 120, it's at 179. Are there still three phases?
Now I rotate it one degree more, to 180. Are there still 3 phases, yes or no?
Now take away the 240 phase. How many phases now? If it's not two, explain why.
And if it is two, then again, it's now ELECTRICALLY IDENTICAL TO 240/120 se rvice. IF you believe it's electrically different, explain why and how it matters in terms of the behavior of the electrons in the service conductors.
Problem number 4:
Draw the basic circuit model of 240/120 service. My model uses TWO voltage sources, with a shared neutral. One is 120V sin(wt), the other 120V sin(wt+180) or of alternate polarity connection, if you like. That is the only way to model that circuit, because that is what is there. When you center tap it, you now have TWO voltage sources. Which by the way is exactly what the professor is saying, you have two sources, 180 out of phase with each other, that's how you treat it. Do you agree with that? If not, tell us your alternate model .
Problem number 4:
Someone asks why they can't randomly parallel any two receptacles in a hous e. My answer is, because you have two 120V voltage sources that are 180 deg out of phase with each other with respect to the neutral or of alternate po larity if you like. You can only parallel ones that are of the same phase or polarity. Your answer?
I clearly said *I believe* you said that it would be two phase. But it's hard to keep track, because you won't answer a simple series of questions, instead you bail out, claiming you can't answer a simple question about whether a phase still exists when I change the angle from 90 to some other choice, because "that system doesn't exist". So much for electrical engineering, now it's claimed that we can only analyze that which is actually deployed. That would get expensive fast.
So feel free to give us your definitive answer to the above simple question. Here it is again, go step by step:
According to Fretwell, two phase power existed 100 years ago, and it was over two wires, 90 degrees phase difference. Suppose I run it over 3 wires instead, with a shared neutral, make it 120V from each phase to the neutral. So, you have a generator supplying 120V on each of two windings on the same shaft 90 deg phase difference, one shared neutral. Would there still be two phases there?
So now, I run that from the generator into a house, we have three wires, shared neutral, 120V, two phases, 90 deg phase difference, correct? I could hook a scope up to the neutral and see two phases, 90 deg apart, correct?
If I change the phase difference to 179 degrees instead of 90 by rotating one coil, are there still two phases? Yes or no?
Now I rotate it to 180 phase difference. Are there still two phases, yes or no? If you disagree, explain how it's different, how there suddenly there are not two phases there, where one phase just went.
(My answer is yes and the final step above makes it absolutely IDENTICAL to what you have coming into the house with 240/120. The electrons are behaving exactly the same. )
The nonsense is that they are out of phase with each other. It is one continuous winding, It is wound in one direction and all of the current flows in the same direction at any given time. That is one phase.
The secondary winding is one continuous conductor with a tap fastened in the middle. But the tap is unused to provide 240 volts. You could remove the tap and sit on it and you would still have 240 volts single phase. Get it?
Already addressed that in another post just now. I clearly said "I believe". Rather odd you're objecting to that suddenly, I've been posting the same thing for two days. It's hard to keep track of your positions, because you won't go through those simple examples, one question after the other. Instead you new position now is that theoretical questions about phase angles or configurations other than what exists can't be answered. That's quite a remarkable position.
Here is the simple problem again, perhaps you'd like to answer it here, all the questions and set the record straight? I;ll give you both problems again, the first where I morph the old 90 deg two phase into
240/120 service, the second where I morph 3 phase. Where oh where did those phases go?
According to Fretwell, two phase power existed 100 years ago, and it was over four wires, 90 degrees phase difference. Suppose I run it over 3 wires instead, with a shared neutral, make it 120V. So, you have a generator supplying 120V, two coils, one shared neutral. Would there still be two phases there?
So now, I run that from the generator into a house, we have three wires,
120V, two phases. If I change the phase difference to 179 degrees instead of 90 by rotating one coil, are there still two phases? Yes or no?
Now I rotate it to 180 phase difference. Are there still two phases, yes or no? If you disagree, explain how it's different, how there suddenly there are not two phases there and where one disappeared to.
(My answer is yes and the final step above makes it absolutely IDENTICAL to what you have coming into the house with 240/120. The electrons are behaving exactly the same. )
Problem number 3
I take 3 phase power with a neutral into a house. One phase is at zero, one is at 120, one is at 240, correct? I can see them on a scope, yes?
Now I rotate one coil so that instead of 120, it's at 179. Are there still three phases?
Now I rotate it one degree more, to 180. Are there still 3 phases, yes or no?
Now take away the 240 phase. How many phases now? If it's not two, explain why.
And if it is two, then again, it's now ELECTRICALLY IDENTICAL TO 240/120 service. IF you believe it's electrically different, explain why and how it matters in terms of the behavior of the electrons in the service conductors.
I have answered you silly quiz TWICE At least as much as you can answer nonsense questions. I prefer to live in reality and not some theoretical world where only pink unicorns and blue oxen live.
I have to stop you there. You are just full of shit. Two phase requires FOUR ungrounded conductors. They either look like an X or T but they still act like an X
S L O W L Y When you rotate to 180 you have ONE PHASE, no matter how many times you tap the output source. A 180 degree phase angle is no angle at all it is a straight line.
OK, so we agree, if you take a 3 phase power source and rotate one winding so that instead of 120 degrees, it's at 179, there are still 3 phases.
Wow, that's a stunning answer. Are you sure that's your answer? Your final answer? By rotating that one winding from 179 to 180 degrees suddenly this whole generator went to single phase? And I'm the one accused of parlor tricks?
In my world, the real word, you still have 3 phases, 0, 180, 240. Before the change you had 0, 179, 240. You'd of course see exactly that on a scope. Anything else would be magic indeed.
... and I have been telling you for days, what you say about 2 phase is simply wrong but you keep posting it. Telling a lie over and over does not make it true. You really are starting to sound more like your buddy trump every day.
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