I was directly addressing the equivalent circuit point you made.
Why is residential wiring known as single phase?
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No, the phase of one is (wt), the phase of the other is (wt), you just switched probe direction so your graph is inverted for the second.
They're easy to equate. Fix your probe directions and they both become (wt). YOU are the one dropping negative signs. Instantaneous power flow is always in one direction across the entire coil. It doesn't reverse at the neutral. Measure with the power and you get (wt). Measure against the power and you get -(wt+180) or simplified (wt). There is no displacement to ignore. I CAN argue with your voltage description because it's a voltage gradient, A & B are not independent of each other not in anti-phase.
Don't tell me you can't recognize a basic AC voltage divider Laszlo. That would be embarrassing for you.
A lot of people in the industry still refer to the low lead in a typical 24VDC circuit as a neutral too. And everyone understands what they mean. But for a technical discussion - it's flat wrong.
Close but not quite. With two phases at 180 the neutral is always the sum of the two circuits; they act independently. With one phase as we have, unbalanced loads alter the whole phase such that the power factor is distorted, they are dependent.
This is a voltage divider circuit. Hence, an infinite number of voltages are available and can be tapped in either direction.
Two transformers would not be a single source.
We aren't combining two smaller forces. The concept never loaded the sources independantly. The loads were applied across the entire series not just one leg. And it was referred to as matched phases not single phase.
LoL. Such nonsense. This circuit has a distinct, linear, single solitary voltage gradient in a distinct, linear, single solitary direction in the direction of power flow at all times. During the first half cycle the power flows from A to B and therefore the voltage gradient is from A to B in proportion to the power flow. During the second half cycle the flow is from B to A and the voltage gradient is from B to A. Continuous, linear, uni-directional at any given instant in time.
Negative signs applied to voltage mean only one thing - the direction that power wants to flow. Assigning A=120, N=0, B=-120 means power flows from A to N to B. One direction. Properly it should be described as AN=|120| with current flow from A to N. and BN=|120| with current flow from N to B. Pick any spot on your scope display. The difference in magnitude between A & B doesn't show "phase"; It shows instantaneous data of the voltage gradient between A & B, the direction of current and power flow between A & B. It shows the instantaneous gradient.
As to the Earth, the different layers of atmosphere, humidity, wind, etc create numerous voltage sources. Not exactly an apt comparison to a single solitary secondary winding.
No. Two combined "in-phases" source would be called matched phases not single phase.
No. The two forces obtained from the output are never opposed. What part of the alternating in AC are you missing? They are always in sync. They are always pushing in the same direction. They are never independant. They are never opposed. If they were actually opposed then we would have a phase-to-phase short.
No. First, as you stated above you can only create this equivalent if you use two sources with matched phases. Matched means both are at (wt), neither is at (wt+180). Otherwise we'd get arcs. Then, if the two coils are independently loaded as they frequently are in residential use you wouldn't get the PF distortion provided by single phase.
Voltage is an artifact of power not the other way around. As long as you ignore that power is flowing through the secondary you'll never be right. As long as you ignore the direction of power flow through the coil you'll never be right. And as long as you keep insisting the caboose is traveling in the opposite direction of the engine you'll never be right.
Rbalex, I really wouldn't want to argue math with you. And I'm pretty good at math. Since they aren't setting the original equation up correctly they're never going to get the correct result. Voltage measurements are how we determine the direction of power flow and not the other way around. Reset your equations to model power and the two equations become (wt) and -(wt+180).
I really wish someone would post diagram #1004 in something other than photobucket.
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Rereading my answer, i can see where there may have been some confusion.
What did I say wrong?
One diode conducts while the current is flowing in the direction of A towards N and from N towards B. The other diode conducs at a different point in time, when the current is flowing from B towards N and from N towards A. Two different diodes two different conduction periods.
My second statement related to; if your voltages are relatively in phase with your currents.
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Nonsense! Both V1n and V2n are defined relative to N, therefore they must be measured relative to N, and Besoeker's full wave rectifier would only be half wave if they were in phase. You demonstrate a poor understanding of what a reference is all about. You would do well to lay off the sniping!
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It would work fine - it must, since the phase
If you had quoted the phrase in full context (I underlined it):
The above quotation is correct. The phase of the transformer secondary voltages is not defined by the resultant current flows, whether conventional, rectified, clipped, "shaded-pole," etc. - or even none at all (open-circuited).
I'd prefer to stay out of the "oscilloscope-jungle"; I don't need an oscilloscope or a graphic from one to understand phase correctly. I only need the characteristic equation of the voltages being compared.
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I'm not trying to model power - I'm modeling transformer secondary voltages. Let's not drag in another red herring.
Um, first of all, Thanks Jim. I wanted to say that before:
:rotflmao:
What part of AC did Besoeker not understand?!?
In a single phase Alternating Current circuit: Power flows from top to bottom during one half of the AC cycle. Power flows from bottom to top during the other half of the AC cycle. There's only ONE cycle running across that coil. By any decent definition A thing is A thing not TWO things.
So we're arguing over this because some people can't understand that their circuit should be modeled for each peak like a DC circuit?
Not a red herring. As long as you limit the discussion to voltage, Mivey wins. Because he's playing scarecrow to Dorothy. He's dropping a negative on you. But if you're gonna insist on voltage anyway, then model the equivalent DC circuits for T=90 and T=270. That should point out his inversions. He's using his neutral reference convention to measure both directions at the same time and claiming it's only one direction.
ex. If I face south the south pole is forward. If I face north the north pole is forward. Therefore both poles are "away" from me and therefore in a positive direction. Both are +(half a world away).
We do NOT switch probe leads. We leave the ground clip on N. As Bes says, we would knacker the scope if we put the ground clip on V1 or V2.
Of course you don't switch probe leads. Which is EXACTLY your problem. As I stated, you need to correct your probe DIRECTIONS if you want to see it correctly. "Away" is not a valid choice of direction for establishing "Positive". "Away" is pointing in two distinctly different directions like the scarecrow in the Wizard of Oz. As to knackering your scopes, try getting a better scope with isolated probes. Stop wearing Wal-Mart shirts in a fashion show.
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