But out of phase so they can't be the same phase. Ergo, you have more than one phase.
May I ask a question about the single vs two phase stuff
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LarryFine
Master Electrician Electric Contractor Richmond VA
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Therein lies the crux of the debate. I would say it as "V1-to-N" and "N-to-V2" instead. You're "artificially creating the inversion" when you keep one theoretical probe on the neutral while moving the other theoretical probe to both, or opposite, sides of it.
Meaning that, for this one instance, what is a polarity phenomenon merely resembles a phase shift
LarryFine
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But, they're not out of phase. They couldn't possibly come from a single transformer if they were. Every winding on a single transformer core is in phase with all of the others.
Like batteries, you must get the polarity correct when combining them. That it's AC doesn't change this, since they all swap polarity in sync twice per cycle; instantaneous polarity.
The same reason a universal motor works on AC or DC.
ggunn
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This isn't a debate, it's a silly argument that will not change anyone's mind. Pass the popcorn.
They are 180 deg out of phase.
Call it anything you want but it doesn't negate that point.
wwhitney
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For a pure sine wave. Add any even harmonic, and they are no longer 180 degrees out of phase. But they would still be negatives of each other.
Cheers, Wayne
LarryFine
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Because they are 180 degrees out of phase.
Adamjamma
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under this thought, you cannot create a three phase power supply from a single phase...
The windings of the core is what creates the phases... the sine waves are proof of the phases. I mean, I may not understand all the math you guys are quoting... Even for AM/FM Phase shifting radio theory I did not get into some of these calculations, but I know that proper windings on a transformer can create phasing that is of various shift patterns form the original phase. This is how some of the transposing ciphers were created in the later part of WW2 and are used in military communications in some parts of the world even now.
The standard transformers form three phase to single phase, or even the so called Center Tap transformer are all used to create phases.
ggunn
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A transformer that creates a balanced audio signal from an unbalanced one works exactly the same way as a transformer that creates 120V - 0V - 120V from a single phase of power. Its output is the signal and the inverted signal, and they are colloquially called "180 degrees out of phase" but they aren't because every frequency is inverted. No amount of phase shift can do that.
But I said that nearly 1200 posts ago, didn't I?
wwhitney
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No.
Suppose due to harmonics the L1-N voltage is of the form sin(x) + a*sin(2x) [for some constant a and where I've set other constants to 1 for simplicity]. What's the L2-N voltage for an idealized center-tapped transformer secondary:
1) sin(x + pi) + a*sin(2(x + pi)).
2) - sin(x) - a*sin(2x)
In this case the two answers differ. And (2) is correct, (1) is incorrect.
Cheers, Wayne
You made my case. Very eloquently.
jaggedben
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A transformer that creates a balanced audio signal from an unbalanced one works exactly the same way as a transformer that creates 120V - 0V - 120V from a single phase of power. Its output is the signal and the inverted signal, and they are colloquially called "180 degrees out of phase" but they aren't because every frequency is inverted. No amount of phase shift can do that.
But I said that nearly 1200 posts ago, didn't I?
I don't know, seems to me that 1149 is a few short of 'nearly 1200'.
Stop exaggerating.You also said it (or made closely related points) in posts 45, 258, 268, 336, 439, 504, ... I'm sure there were a couple more. Sorry I got bored of searching.
jaggedben
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Are they 180 degrees apart?
That's just yes or no.
jaggedben
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Yes. Two phases (with respect to time) in a single phase(with respect to function) system. GLAD I AM ABLE TO COMBINE TWO CONTRADICTORY COCEPTS INTO ONE! That is dialectics of development.
LarryFine
Master Electrician Electric Contractor Richmond VA
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It only resembles an offset in time; it's an opposition in instantaneous polarity.
If you were to change the frequency but maintain what you perceive as the "timing offset" between the two waves, the opposing peaks would no longer occur at the same time.
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