OK, then let's take the existing three phase, 0, 120, 240 system. I connect a resistor between the 0 and 120 phases. Now exactly like you just did with my two phase example, we have a new phase also correct? Does that make it 4 phase power?
I don't know why you can't separate what exists, what;s efficient, what's practical, what has been actually used, from what you can construct, what you can analyze, using basic electrical engineering.
Again with the transformers.
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That now because of the tap, behaves as TWO separate voltage sources. If you disagree, draw for us the circuit diagram that models it without using two 120V sources. That's what you don't get. If it's just 240V power, you can model it with one 240V source. As soon as you center tap it, it's now two voltage sources, that are 180 deg out of phase with respect to the system neutral/reference point.
Actually there is not a single trig function in that math.
scope common lead on L1. Attach one trace probe to the secondary tap and the other trace probe to L2.
plitude. Pure single phase.
You can't ignore the central tapped neutral as if it was some insignificant detail. It's the whole, essential point of the circuit. By center tapping it and defining that center point as the system NEUTRAL and reference point , you have created TWO 120V voltage sources. The parlor trick is to only put the scope across the two hots and ignore the very important phase relations hip between each hot and the neutral/reference point.
Draw us the model circuit that shows what's going on there without using TWO 120V voltage sources that are either 180 deg out of phase or of opposite polarity, which is the same thing. It can't be done.
Please, stop playing games. I gave you two scenarios, one with 90 deg two phase, one with 3 phase, where step by step I morphed them into electrically exactly the same thing as the electrical service into your house. It's those theoretical examples that you run from and made the bizarre claims that it can't be analyzed because it's a "pink unicorn" that doesn't exist. IT's what you have to do, because if you stick with those simple examples, you're left with the fact that I can morph the old two phase 90 or today's 3 phase into what looks and behaves and is indistinguishable from 240/120 service. And it's two phases.
Sigh, back to the transformers again.
So now having a generator with two windings and a shared neutral is bogus? Taking a 3 phase generator that's 0, 120, 240 and moving one winding to 179, 180, 181 is bogus? Only in your world, because the logical and correct progression from there turns it into what is identical with
240/120 and you can't allow that to be. In reality they are very simple scenarios. (And no transformers are necessary or involved)All I'm doing is looking at what the power service into the house looks like, performs like and is. Again with the transformers. It doesn't matter to the water heater, the TV, the engineer using the service how it came to be. All that matters is what's there, how it performs. If I tell you that you have two hots, 120V each, 180 out of phase with each other with respect to the shared neutral, that each can deliver
200A, what more do you need to know to be able to use it? ?? ?? What more?I tell that to any electrical engineer, they use it. They don't need to know if it came from a transformer, a home generator, was synthesized electronically from a UPS with a battery, or came from those two examples I gave you where I morphed it.
Show us where 180 is excluded from being a legitimate phase. All the equations, all the electrical engineering I've even seen, work with any phase angle.
That's the other poster already addressed. IT's like saying there is no north and south, only north and north.
By what law of physics is that? If it requires two isolated windings, four conductors, how is it that we can get 3 phases with just 3 wires?
They could have any angular
Irrelevant of course.
Two phases, which is precisely my point. If you have two phases at 90, two phases at 179, two at 181, then you have two at 180. It's all consistent. Otherwise there is a "parlor trick" at 180.
And you keep being ignorant of the fact that what you describe will end up being 3 phase delta. In fact when I showed you a typical 3p delta done with 2 windings (transformer or generator, makes no difference) you tried to tell me it was 2 phase. You just do not know what you are talking about so it is hard to take your questions seriously.
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According to you no one here knows what they are talking about except you. The IEEE Fellow, prof, power engineer, he's confused too. He's using trig functions in his analysis, even though there isn't a trig function there. You can't deal with a very simple generator with two windings. According to you, it's impossible to have two phases from a generator without
4 wires. Which of course is BS. How then do we get 3 phases with just 3 wires? Explain that? Hello?I take two windings, put them on the same shaft, separated by N degrees. I tie two of the ends together, forming a common neutral. That defines a TWO PHASE POWER SOURCE. It really is that simple. The only thing that determines when the AC sine waves crosses zero and start to rise is when the magnetic field passes the windings! It's defined by the physical configuration of the generator, where the windings are on the shaft, not the loads. I put a resistor from one winding to neutral or the other winding to neutral, does it change when the magnet passes the winding? No I still have a generator putting out two phases at N degrees separation. I put a resistor between one hot and the other, does it change when the magnet passes the winding? NO. Those two phases are still there, N degrees apart. It really, really is that simple. No transformers are involved. If we have 3 phase and put a resistor between two phases do we now have 4 phase power? It would be exactly the same thing. Put 3 resistors between the phases and what now, 6 phases? Of course we still have 3 phases at exactly the same phase angles which are DEFINED by where the windings are on the shaft. It's defined at the 3 phase generator, it's defined at the two phase generator.
These people don't know what they're talking about too? :
"2-Phase-3-Wire-System_Problem-1430295633
A 2-phase, 3-wire AC system has a middle conductor of same cross-sectional area as the outer and supplies a load of 20 MW. The system is converted int o 3-phase, 4-wire system by running a neutral wire. Calculate the new power which can be supplied if voltage across consumer terminal and percentage l ine losses remain the same."
According to you, it can't exist. And don't tell us because it hasn't been built it can't be analyzed. Their example is EXACTLY my example.
Fretwell's new interesting position is that phases disappear if they are 180. And that also somehow also kills off other phases, because he says if I take a 3 phase system and move the 120 phase to 180, POOF, it becomes a single phase system. That poor 240 deg phase, IDK what happened to it. He also said something about if I make the 120 phase to 179, then it's still 3 phase, but if I make it 181, then somehow POOF it might be the same as 179? But for sure at 180 that phase disappears.
In my world if you draw the phasor diagram for 3 phase, it has 3 phases and always will, as long as there are 3 windings at different angles on the shaft. And if one happens to be at 180, that's where it is. Curiously, if I ask a student to analyze what's coming into a house and draw the phasor diagram for it, what would he draw? It would be two 120V vectors, one at 0, one at 180 degrees.
Which again is totally consistent with what I said about voltage, phase and ampacity being all you need to know to define and analyze the service into the house. If I tell you this about the service:
60 Hz sinusoidal sources It's 3 wires, shared neutral. Two 120V voltage sources, 180 deg out of phase from each other with respect to the neutral Each voltage source can deliver up to 200 ampsDo you need to know anything else to design with it? To analyze it? To explain what you see, what's going on? Do the appliances care that it came from a transformer, generator or synthesized from a battery?
I get three phase with three wires very easily. If it is a delta you have phase A, B and C That is three. Look at any high voltage transmission line to see it out in the open for all to see. That is 3p, ungrounded, delta. (not to be confused with the medium voltage 3P wye used some places for local distribution)
If you have any phase shift between winding 1 and 2, the third phase will just show up on a poof. I showed you a picture that you keep calling 2 phase when it is clearly labeled 3P delta. Should I find you more? Just measure the voltage between the 2 unterminated ends. In fact that is what this shows (V-BC) You might also look for "open delta" since delta V will bring you a lot of articles about "velocity". The only thing I see strange in the articles I read is they talk like it is unusual. We have open delta services all over around here., It is a cheap way for FPL to give a small user 3 phase (2 transformers) I don't have to drive far to see one.
If you think you see an oddity like that (phase disappearing at 180), there's something wrong.
I'm beginning to understand about 2 phases making a 3-phase delta system, but there's still something wrong with that "disappearing phase(es)".
Your scenario was 2 windings and if 2 windings have no angular displacement (wound around the core, generator or transformer in the same direction and excited in the same axis magnetically or mechanically), the output is single phase.
In a 2 winding 3p system the 3d phase is induced by the angular displacement of the other two.
Fretwell's correct!
If you think of it as a snapshot in time, you essentially have a dc charge on each of the coils. If the 2 coils are 180° apart, then the instantaneous charge voltage on the first coil will always be the opposite of the second coil.
For example, below I have two identical coils mounted on a shaft with the second coil mounted 180 degrees with respect to the first. The two coils are connected in series as shown.
The output of the second coil will always be the opposite polarity of the first coil.
------ [ (+) polarity of coil at 0 degrees (-) ] ---------- [ (-) polarity of coil at 180 degrees (+) ] ------
Since the two coils are always at opposite polarity to each other, they would in fact cancel each other out. (Think of it as a 2-cell series battery pack where some clueless democrat put one of the cells in backwards.)
And FWIW, this instantaneous snapshot also illustrates why the ubiquitous residential center-tapped transformer is not 180 degree 2-phase.
It is not odd but if you do have 3 windings and one comes off the center tap of the single phase winding (Traders rotated to 180) you actually do see 2 phase. That is the Scott T connection I have talked about but it required 3 windings in a wye, not 2 end to end. You also get that illusion on a scope if you look at a center tapped delta. You will swear you are looking at 2 phase with a 90 degree displacement but your 3 phase motors are happily humming along. It is pretty much impossible to scope that pretty 3 phase signal you see in the book even if you "float" the scope..
Good grief, from the very beginning I have had the winding with differing angles in each of the two very simple examples I gave you. In this example it was 3 phases. One at 0, one at 120, one at 240. That is 3 phase, yes? So now I rotate the 120 winding so it's at 179. You said that was still 3 phase. So, if I drew a phasor diagram, I'd have three vectors, one at 0, one at 179, one at 240, you agreed with that. Now I rotate it one more degree to 180 and POOF, it's gone? Your phasor diagram would now have only two vectors? And why would that not be two phase, since there are only two in your world?
My world, there are still three vectors and it's still 3 phase. It's easy when you know the rules and apply them consistently.
e on each of the coils. If the 2 coils are 180° apart, then the instantaneous charge voltage on the first coil will always be the opposite of the second coil.
second coil mounted 180 degrees with respect to the first. The two coils a re connected in series as shown.
Duh! Opposite polarity is the same thing as 180 deg phase difference.
---------- [ (-) polarity of coil at 180 degrees (+) ] ------ould in fact cancel each other out. (Think of it as a 2-cell series b attery pack where some clueless democrat put one of the cells in backwards. )
I see, so the two 120V voltage sources coming from the transformer into my house cancel each other out and I have zero volts? Nice.
Let's go back to the generator. I want to make sure I get you on record. I have a 3 phase generator with windings separated by 0, 120, 240 degrees. I ask you to draw the phasor diagram for it. Mine and everyone else in the world who knows WTF they are doing, draws it with a vector at 0, a vector at 120, a vector at 240. How do you draw it?
Now I rotate the 120 winding to 179. Fretwell says that's 3 phase, IDK what his diagram is, but hopefully it a vector at 0, one at 179, one at 240 ? What's your diagram?
Now I rotate it one more degree. My diagram has one vector at 0, one at 18
0, one at 240. Yours? If the one at 180 is gone, there is your parlor trick. It would really be something. At 179 I had a vector, a winding that was delivering power, that could be analyzed just like any other phase vector. But now because it happens to be 180, it's gone? Since it's no longer on the phasor diagram, you can go grab hold of it, there is no voltage, no power there, right?It's amazing how you can't grasp the basics.
residential center-tapped transformer is not 180 degree 2-phase.
Quite the opposite, it shows that it is, just like the IEEE Fellow, prof of electrical engineering, who consults for utilities said in his paper that he presented to his peers at a power industry conference, published by the IEEE. Why don't you try drawing the phasor diagram for it ? Mine is two 120V vectors, one at 0 deg, one at 180 deg. Show us your phasor diagram that gives you 240/120 service.
I noticed you did not respond to the numerous posts that showed you 3 phase delta with two windings. These exist on poles all over the country, not in your fertile imagination.
Not really but if you believe that the rest of your rants are right. I just want to know how you can generate a phase difference in one piece of wire without a capacitor?
You have made a discovery that Tesla and Westinghouse seemed to miss.
I notice that you almost never respond to what I post, instead diverting to transformers. Transformers are not required and are a redirection to the wilderness.
I ask again, draw a phasor diagram for a 3 phase generator. You have vectors at 0, 120, 240 deg, yes? They represent PHASES, with voltages, power that are real. Now rotate the 120 phase winding to 179 deg. You say we still have 3 phases. Let's draw the diagram again. We simply move the 120 vector over to 179. And you say that still represents 3 phases. Now I move the winding to 180 and we suddenly have two very different views of what is correct.
I say you simply move the vector one degree, you now have a 3 phase diagram with vectors at 0, 180, 240 deg. It defines and explains what is there.
You say that POOF, somehow now I have single phase. I still haven't heard your version of the new diagram, but presumably the 180 phase vector just disappeared? If so, where did it go? Those three vectors represented voltage and power, I just lost one by moving it one degree? Does that make sense from anything you know about physics, science, electricity? Can I now grab hold of that 180 phase? If not, then there must be voltage there, power there, yet it's not on the phasor diagram?
And if you follow my generator example to the next step, which is to get rid of the 240 winding, then you have two vectors left, one at 0 deg, one at 180 deg, and the service into a house.
BTW, the phasor diagram explains your open delta configuration too.
And I can draw a phasor diagram that represents the 240/120 service into a house. One 120V vector at 0 degrees, one 120V vector at 180 degrees. It all works beautifully, it's all consistent. Where is your alternate phasor diagram for that, where there are not two vectors?
Again, if I tell an electrical engineer that they have a three wire power source where:
two 120v voltage sources share a common neutral one source is 180 deg out of phase with the other either source can deliver a max of 200A
That's all they need to know to analyze it, use it, design with it. It doesn't matter if it came from a transformer, generator, or synthesized from an electronic black box. They can draw the phasor diagram that represents it. It's the 3 wire service into a house.
arge on each of the coils. If the 2 coils are 180° apart, then t he instantaneous charge voltage on the first coil will always be the opposi te of the second coil.
the second coil mounted 180 degrees with respect to the first. The two coil s are connected in series as shown.
the first coil.
An inductor would be one way. But we don't have one piece of wire. We have 3 wires, two hots and a shared neutral. One of those hots is of opposite phase, opposite polarity, with respect to the other. It has to be, it's the very essence of how the circuit works. And from that, all electrical engineering analysis flows.
An inductor and a capacitor, like how they split the phase to start a motor
The secondary is one piece of wire. You just tapped it 3 times.
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