Why is residential wiring known as single phase?

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Besoeker

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UK
Your hexaphase drawing does not have all the windings going the same way (I mean like clockwise) as looking out from the neutral. I believe you drew it that way to show some sort of relationship between hexaphase and single phase.
Don't read too much into it.
The drawing does not show winding direction.
I mirror imaged some of the legs to avoid clutter, nothing more.
The phase relationships I gave are the import issue.
 

jcassity

Senior Member
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with respect to post 24 and 27, your source is still one drum of water no matter how many times you "TAP" into the source.

if you want another phase, your going to need another drum.
 

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jim dungar

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Definitely a moving target. Sometimes I agree with Jim, sometimes not. The best I can tell it is a preference and terminology difference.
Thanks.

I believe there are many valid, and often easier to explain, analysis methods that can be used.

I do not say there is only one set of math equations, nor that there are not multiple ways to possibly physically connect transformer windings, however I do say there is one way they are actually physically connected.

Some of the possible connections we have
Center tapped, single winding: X1->X2->X3
Series additive, two windings reconnectable: X1->X2+X3->X4
Series subtractive, two individual transformers : X1->X2+X2<-X1
 

jim dungar

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What effect does swapping the direction of the windings have on the output of a transformer?
It has a huge effect. Basically your windings are connected so they subtract instead of add. This is one reason I promote considering the connections of the source.

But, be careful a cut-and-paste drawing, usually does not represent the actual winding directions.
 

Rick Christopherson

Senior Member
Yes, but it is sufficient to demonstrate that it is an inversion, not a phase shift.
Just a follow-up. There is no argument that mathematically an inversion can appear as a phase shift. That's why it is perfectly fine to say they are "equivalent", and you'll get no argument from me.

Where you're going to get an argument from me is when you say it is a phase shift instead of just being equivalent to one. If it truly was a phase shift and not just a mathematical equivalency, then the setup I described above would show the noise on both positive peaks.
 

rbalex

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I liked the idea, and I appreciated the different viewpoint, but the math was wrong.

...
Assuming you know the difference between a function and an equation, the math wasn't wrong - you simply refuse to differentiate between a function's phase value and the function itself. Disagreeing with me is fine of course; I'm not the authority. But explain my misapplication of "phase value" of a function from my orignial reference to a Cal Tech PhD's definition of phase as it applies to mathematics.
 
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rattus

Senior Member
Just a follow-up. There is no argument that mathematically an inversion can appear as a phase shift. That's why it is perfectly fine to say they are "equivalent", and you'll get no argument from me.

Where you're going to get an argument from me is when you say it is a phase shift instead of just being equivalent to one. If it truly was a phase shift and not just a mathematical equivalency, then the setup I described above would show the noise on both positive peaks.

So without the noise, it really is a phase shift? But what does this have to do with the original question?
 
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Rick Christopherson

Senior Member
So without the noise, it really is a phase shift?
No. The noise simply reveals that it is not a phase shift, but can be expressed as one mathematically.

But what does this have to do with the original question?
You keep trying to sidestep the discussion to avoid answering it. So for now, let's pretend that it has nothing to do with the OP, and focus strictly on how it relates to your previous statement.

... then V1n and V2n are as Bes says antiphase. They don't just appear to be so, they are. ...
 

mivey

Senior Member
Assuming you know the difference between a function and an equation, the math wasn't wrong - you simply refuse to differentiate between a function's phase value and the function itself. Disagreeing with me is fine of course; I'm not the authority. But explain my misapplication of "phase value" of a function from my orignial reference to a Cal Tech PhD's definition of phase as it applies to mathematics.

I did explain but you did not understand. The zero subscript in your "PhD reference" is indicating the constant portion of the phase at the initial condition. By removing the 180 degree portion of the constant your placeholder no longer represents the initial condition constant.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
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Electrician
Don't read too much into it.
The drawing does not show winding direction.
I mirror imaged some of the legs to avoid clutter, nothing more.
The phase relationships I gave are the import issue.

Well, if winding direction is not considered, then the comparison you offered is not as you posted it.

It has a huge effect. Basically your windings are connected so they subtract instead of add. This is one reason I promote considering the connections of the source.

It would help me if you could re-draw the hexaphase system taking winding direction into consideration. I think if you did that you would have six windings, not three center tapped windings. If my mental image is correct, in a hexaphase system, the phases that were 180 out would have windings that change direction at the neutral, thus a comparison to any 180 degree offset pair to a single phase center tapped winding would be inaccurate.
 
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rbalex

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I did explain but you did not understand. The zero subscript in your "PhD reference" is indicating the constant portion of the phase at the initial condition. By removing the 180 degree portion of the constant your placeholder no longer represents the initial condition constant.
OK, so subscript phi with zero - the phase values of the reduced voltage functions will still be the same. You just don't seem to understand extracting an element of a function is valid. That's OK - I do.
 

mivey

Senior Member
Well, if winding direction is not considered, then the comparison you offered is not as you posted it.



It would help me if you could re-draw the hexaphase system taking winding direction into consideration. I think if you did that you would have six windings, not three center tapped windings. If my mental image is correct, in a hexaphase system, the phases that were 180 out would have windings that change direction at the neutral, thus a comparison to any 180 degree offset pair to a single phase center tapped winding would be inaccurate.

No, the windings do not change at the neutral.
 

mivey

Senior Member
OK, so subscript phi with zero - the phase values of the reduced voltage functions will still be the same. You just don't seem to understand extracting an element of a function is valid. That's OK - I do.

I understand that extracting it is perfectly fine. What you fail to understand is that by doing that you are saying that the phase at one location on a waveform is the same as the phase at a location that is not an integral of the function's period. Total nonsense.
 

jcassity

Senior Member
Location
24941
interesting,, ok here is another angle in attempt to get this back on point....

here is the formula

post 1 + post x = post 1 answer

i figure if i over complicate the simple stuff , it may encourage the posts to stay on point.
 

roger

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interesting,, ok here is another angle in attempt to get this back on point....

here is the formula

post 1 + post x = post 1 answer

i figure if i over complicate the simple stuff , it may encourage the posts to stay on point.

I see it as post 1 = post 2
;)


Roger
 

rbalex

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Professional Electrical Engineer
I understand that extracting it is perfectly fine. What you fail to understand is that by doing that you are saying that the phase at one location on a waveform is the same as the phase at a location that is not an integral of the function's period. Total nonsense.
No - I'm not. I'm saying the characteristic function of the phase value reduces to the same - which it does; sign being irrelevant to establish phase.

My explanation is consistent with why we call conventional systems, "single-phase,""two-phase," and "three-phase." Those designations have been around longer than either of us and there was a better reason than, "Well, we gotta call it something."(edit add: the post 2 answer:D) It even applies to the currently discussed "six-phase" system where the phase value elements are reducible to six - 30? increments.
 
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