Nice snipping job. Funny if I'm just a dumb homeowner that I could define N phase power for you, when none of you "experts" could. Also quite odd that I can answer all those simple circuit 101 questions, without diverting to talk about transformers in the wilderness. I'm comfortable in my knowledge. I'm sure the IEEE Fellow that I cited is too, regardless of your attacks on him. I know you're mad, it's what happens when you can't answer simple questions.
OK, so you agree there are 3 phases, 0, 120, 240. It's a wye with neutral coming out of the generator. I run that into a house, it's 3 phases, correct?
Now I rotate one winding so that instead of 120, it's at 140 or 179 deg, is it still 3 phases?
That's just total BS. If that's the case, what do you do in FL when your power goes out? I plug in a generator, one proof that you don't need a transformer.
I just did with the generator, no transformers required. And the laws and rules of electrical engineering apply to all cases, we don't need to have something actually implemented to analyze it. This is a very logical analysis, what happens if I change a phase angle from 90 to 120, to 180. It's all explainable if you understand electricity and apply what you know consistently.
PoCo generators make delta but OK
Another pink unicorn. Talk real life and I will engage.
It is still a single center tapped winding coming out of the generator producing single phase power. There is no substantial difference in a generator and a transformer except that the magnetic field to the "secondary" is produced mechanically instead of electrically.
I have exactly repeated what he really said. How unfortunate that you can't acknowledge what he said.
In his opinion. And yours. There is no reason to believe distribution engineers and people who work on power systems agree.
You poor abused person.
I'll give you permission to call it whatever you want. But you will have problems if you try communicating with people in the power industry. Manufacturers and design engineers and other workers don't agree.
Geez - I thought trader created 2 phase.
Tesla had patents for 2-phase and 3-phase. He also had patents on many different induction motors. Rights to the patents was bought by Westinghouse. It was almost impossible to make induction motors that did not infringe on Tesla's patents (so competitors just infringed).
The first long distance (almost 3 mi) transmission of high voltage AC was in Europe in 1886 and was a demonstration for lighting. The developers acknowledged that they used Tesla's 3-phase patents.
The first long distance (2 mi) transmission of high voltage AC for power was 1891 near Teluride CO. 3kV, 133 Hz.
The first major win in the "war of the currents" was when Westinghouse (Tesla/AC) won the contract for electrical at the 1893 World Fair in Chicago. If the fair was duplicated now I would want to see it. Westinghouse had to come up with a light bulb that did not infringe on Edison's patents.
The end of the "war of the currents" was when AC was selected for the first large electric hydropower project at Niagra falls (about 1.5 miles above the falls in Buffalo). The generators were on top with turbines in a deep pit and a tailrace tunnel out to below the falls. The first 2 generators were online 1895 and were 2-phase 25 Hz. The adjacent transformer building converted that to 3-phase using transformers and a scheme by Charles Scott (sound familiar?). Transmission lines to Buffalo were 3-phase. The first power building eventually had 10 generators, and a second similar building was built.
In a criminal act of vandalism, all of the Adams (Tesla) plant was torn down except the empty transformer building. The site in now a sewage treatment plant.
GE was the combination of Edison Electric and another manufacturer. Edison was forced out.
Westinghose was also forced out of his company.
Edison funded 'research' that electrocuted many dogs, a horse, and (I think) an elephant. They finally convinced a NY prison to use an electric chair. It was a total fiasco. The poor victim was probably more cooked than electrocuted.
Real electrical engineers can engage on any generator, any number of phases, and phase angle. There is nothing sacred about any specific degrees of phase. And I suspect you know that, it's just that when you have to rotate it to various angles, you know how it leads step by step to being electrically identical to 240/120v, so you won't address it.
And that's why I've tried ten times now to lead you through a generator example where I take what you say was two phase and morph it one small step at a time into what is exactly the same as 240/120 service. It's a perfect valid, very simple, electrical engineering analysis. But you won't admit it because there are obviously two phases there.
I've done the same thing with 3 phase, change one phase angle from 120 to 180, get rid of the conductor that's 240 phase, and you have the exact same thing as your home generator or 240/120 service. But you won't address that example either, calling it a pink unicorn, because it too is exactly the same as 240/120 and you can't explain where a phase disappeared to.
In short, I can address all cases, answer all questions, which are at the circuits 101 first couple of days level. No need to claim something is a pink unicorn. That's why you can't answer those series of simple questions, you're stuck.
Liar. I have acknowledged exactly what he said. I posted it, the whole abstract, I'm the one who brought it here. I didn't selectively edit it out of context and deliberately leave off the next sentence that says EXACTLY what I said at the beginning of this thread. Again, in context:
Abstract: Distribution engineers have treated the standard "singlephase" distribution transformer connection as single phase because from the primary side of th e transformer these connections are single phase and in the case of standar d rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Whic h now brings into focus the reality that standard 120/240 secondary systems are not single phase line to ground systems, instead they are three wire s ystems with two phases and one ground wires.
The odd thing here Bud is that none of you "experts" can address the very simple circuits 101 questions that a student could ask a teacher. I can answer them all, because like the IEEE Fellow above, I can apply electrical engineering basics consistently to do the analysis. You and Fretwell can't answer the questions because you either don't know what you're talking about or you know that the simple examples lead right into staggering contradictions that shows there are two phases there.
Again, perhaps you should read what I post before you come here and attack me? I said in my very first post that I would not CALL it that. Only that from an analysis perspective, you do have two phases there. THAT is exactly what the IEEE Fellow, electrical engineering professor who consults for UTILITES said, in his paper presented to his PEERS at a power industry conference. Why don't you attack him too? This is like saying you can only call the stuff you blow your nose in Kleenex, you can't call it tissue or upon analysis say that it's a soft paper product made from trees.
And if you're so smart, why don't you answer the very simple questions pose d:
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 polarity if you like. You can only parallel ones that are of the same phase or polarity. Your answer?
We live in the real world, not some place where theory trumps reality
The fact remains when you rotate an angle to 180, you have a straight line and there is no phase angle. When you stand in the middle of anything and look both ways, you might think you are looking at two things but it is one thing
A residential transformer secondary is one continuous conductor from end L1 to end L2.
Assuming a purely resistive load on the secondary and ignoring crossings where Volts=0,
at any point in time the current is either flowing from L1 towards L2 or from L2 towards L1.
In order for the transformer secondary to truly have 2-phases 180° apart, the current would have to be flowing from L1 towards L2 AND from L2 towards L1 at the same instant.
And that, my liberal friend, would be the mother of all parlor tricks.
It is not even a parlor trick to actually connect 2 transformers together that are truly 180 out of phase and you would then have 2 separate voltage sources grounded in the middle but you would not have
240v available to you, no matter what you did and no current would ever flow in the neutral.
I don't feel lke getting into this, but ask old T4 what hapens to his 2 phase transformer and 2 chanel o-scope if he hooks the 'ground' to one end of the transformer and looks at the signal withthe other 2 probes at the center and other end.
Then try that with a 3 pahse system.
Exactly. It goes back to simple physics 101.
In general, with a purely resistive load on the secondary, whatever waveform is on the primary is mapped to the secondary. Single phase in, single phase out.
I think troll_4 is just trying to screw with us.
Yah, traitor tries to spread phake news about President Trump, now he's trying to hit us with phake physics too. You might say he's two-phake.
Put that down on as an answer on your circuits 101 test. I can't answer a simple theoretical circuits question because it doesn't exist. I must have it implemented in an actual circuit before me. Do you not see how silly that sounds? The reason you can't answer those questions, one after the other is it leads directly to unanswerable contradictions. When you apply electrical engineering consistently, there are no contradictions.
Complete nonsense. A phase angle of 180 is every bit as real as ones at
90, 120, 179 or 181. At an angle of 180, two voltage sources are direct opposites of each other. It really, really is that simple. Which again is why I can answer all those simple questions a student would ask.
L1 to end L2.
where Volts=0,
from L2 towards L1.
part, the current would have to be flowing from L1 towards L2 AND from L2 t owards L1 at the same instant.
That would be true only if the circuit did not have a center tap. With the center tap it becomse TWO 120V voltage sources. Do you disagree with that? If it does not become two 120V voltage sources, explain how we get 120V with a load on just one side of the secondary.
With two voltage sources, it looks like two batteries stacked one on top of the other. Do that. Put two 9V batteries one on top of the other with a tap between them. You can no longer treat it as just current flowing through both, from one end to the other. You have two conductors now that are of OPPOSITE POLARITY or 180 deg phase difference in the AC world. Put a load on just the upper half circuit and current flows from the upper battery positive through the load and out the neutral back t o the upper battery negative That current is flowing out the neutral, yes?
OK, now instead put a load on the lower battery. Because it's of OPPOSITE polarity, the current will flow from the lower battery positive through the neutral through the load and out the connection back to the negative side of the lower battery. It's current flow in the OPPOSITE direction on the neutral. That is exactly what happens with the transformer secondary. In the special case where the loads happen to be balanced, the two currents in opposite directions cancel each other out and you have zero neutral current.
The essence of the problem here is that you cannot have this service working without TWO voltage sources, one has to be of the opposite polarity of the other with respect to the neutral. Opposite polarity and a phase difference of 180 are the same thing in an AC circuit.
L1 to end L2.
where Volts=0,
from L2 towards L1.
apart, the current would have to be flowing from L1 towards L2 AND from L2 towards L1 at the same instant.
Back to the transformer fetish? Why can't you answer simple questions about a generator with two windings? Good grief. I can.
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. Y
orm is on the primary is mapped to the secondary. Single phase in, single p hase out.
Is the IEEE Fellow, elect engineering professor, with 40 years experience, who consults for utilities, who presented his paper at a power conference of his peers, published by the IEEE, screwing with you too? He says exactly the same thing:
Abstract: Distribution engineers have treated the standard "singlephase" distribution transformer connection as single phase because from the primary side of th e transformer these connections are single phase and in the case of standar d rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Whic h now brings into focus the reality that standard 120/240 secondary systems are not single phase line to ground systems, instead they are three wire s ystems with two phases and one ground wires. F
Maybe you can answer the simple circuits 101 questions that no one else here can answer:
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 went through that with Fretwell already. Look, I was accused of doing a "parlor trick" with a scope. What did I do? I connected the scope ground to the SYSTEM neutral. I did not define the neutral as the reference point, the system designers did. So, it's not a parlor trick to connect a scope as any beginning student would to look at what's going on in that circuit. Connect the scope ground to the neutral, put traces of the two hots on the screen. What do you see? Two 120V voltage sources that are
180 deg out of phase with each other. THAT is the whole point of the Edison circuit! If you believe you can draw this circuit, model it without two 120V voltage sources that are 180 deg out of phase, or of opposite polarity, same thing, then show us how. This is the first couple days of circuits 101. It's the only way to model that circuit, to explain what's going on.Sigh, IDK where you're going with that. Perhaps you'd like to answer the simple questions where I start out with 3 phase and step by step turn it into the same thing as 240/120. And please, if you're going to do it, don't start wandering off into the wilderness with transformers. It's very simple stuff. You'd be the first person here, beside myself, who can answer it:
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.
You can get something meaningful on a 3p wye (there is no center tap). but on any kind of delta the scope will just tell you lies. 3p center tapped delta will look like 2 phase, even showing the B phase 90 degrees out. On corner delta, you will be sure you are looking at
240/480 single phase. You are basically still on a center tap.
If I had 2 generator windings out of phase (opposite current flow, wound in the other direction or how ever you want to define that) same result.
You simply do not know enough about 2 phase to even engage.
Then you just start sounding stupid
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