But we have never considered the primary-secondary coupling. We are merely observing the waveforms on L1 and L2. If they are out of phase by 180, everything is well and good; if they are in phase, we have a problem. Nuf sed!
Center-tap Transformer Voltages
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But we have never considered the primary-secondary coupling. We are merely observing the waveforms on L1 and L2. If they are out of phase by 180, everything is well and good; if they are in phase, we have a problem. Nuf sed!
Because where it was used, it's the correct scientific term. Learn its use in science/engineering and you'll understand better. It means only what it means. It says nothing about what's real or actual. Laymen outside the technical community imply that apparent means not real. Inside the community it makes no such implication.
This is an extension of a prior thread where the two sides failed to understand that the coupling was the reason for disagreement rather than the measurements or equations.
This has been repetitious. You (rattus) are neglecting the transformer in your analysis. For your purposes this is perfectly acceptable. As for how you're writing the equations, since you're neglecting the primary-secondary coupling, do it how you want it.
Okay, we can go with this statement. Just start by accepting that the lingo AGREES with your statement. It does not invalidate, argue against, or contradict what you said.
All observed voltages with a meter or scope are based upon the reference frame you impose upon the system. Tap L1 and call it zero and you get in phase waveforms at N and L2. Tap L2 and call it zero and you get in phase waveforms at N and L1. Tap N and call it zero, as you have, and you get out-of-phase waveforms at L1 and L2. The fact that you can retap at different locations and get different waveforms is why it's called an apparent waveform. Its appearance depends on your reference frame. It doesn't make any of them less real or less accurate. [And yes, I am presuming you're using a scope that doesn't lock it's reference probe to the local ground]
N = 0V is the most commonly used frame for obvious reasons.
Rick et al, in the prior thread were purists. That means they wanted to model the transformer in the circuit. Unfortunately they didn't understand that you were never going to do that. You don't ever have to unless you want to understand why Mivey et al were butting heads with Rick et al. Mivey only modeled without the transformer, Rick only modeled with the transformer.
The discussion relates to AC.
The electrons don't really flow. They just wiggle back and forth and, very little at that.
Polarity and electron flow directions are pretty useless when it comes to discussing alternating current circuit behaviour.
In fact, I think that they are something of an impediment to understanding what actually happens in the circuit.
Rick Christopherson
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"Wiggle" and "very little" are relative terms, and as used, can be very misleading.
Yes, from a human (macroscopic) perspective, the fraction of a millimeter that an electron effectively moves is small. However, from an atomic perspective, this would be comparable to miles and miles of movement. At the atomic perspective, it is not just a wiggle and it is not something to be dismissed off-hand.
Until you stick diodes in an AC circuit. Then the direction of flow matter a great deal.
Were you mislead?
Rick Christopherson
Senior Member
No, but that's because I know better. That doesn't mean that everyone else reading it knows better. That's why we have two-sided discussions to clarify misleading information.
There again, they might.
And it no longer AC.
Rick Christopherson
Senior Member
Well, if you knew that everyone would already know it, then there was no reason for you to bring it up....'cause they already knew it. Right?
So that begs the question: If everyone already understood it and it didn't need clarification, then why did you mention it in the first place?
I made no such claim.
mivey
Senior Member
So some are trying to say the polarity dictates the direction we must call positive for the entire circuit.
For what purpose?
None of this will change the day-to-day operation of the normal EC. This discussion is only about a better understanding. There is no requirement that you participate and learn anything different than what you already know. Simpe tools will probably do everything you will need to do.
pf will impact your life as an EC. And will bite you in the behind if you ignore it.
No biggie. We all have our moments.
Polarity is about the instantaneous relationships between two different parts of a circuit. Not the same thing as direction in general at all.I mean polarity isn't the same thing as direction
really
mivey
Senior Member
From what I can tell, most don't. You can buy them for a lot more $$$. I just use a differential probe with the scopes I have. They run about $300-400 and up.
mivey
Senior Member
Sure, but one way the fall from your head to your feet and the other way they fall from your feet to your head. That's DC.
With an AC signal, you can stand on your head and they will fall from your head to your feet 180? later.
If it means nothing in particular, why apply it when reading voltages one way but not when reading them the other? Its use at all in this case carries an implication.
Precisely.
mivey
Senior Member
Well Dan, this guy you speak of can also get a 240 volt shock by two voltages that are physically displaced by 180?, and their relationship to ground would be very relevant.
mivey
Senior Member
Actually, I have been saying both methods produced real, valid voltages. The other side said one one method produced real voltages but the other method produced voltages that only appeared to be real.
mivey
Senior Member
Exactly, and the difference between AC and DC can be pretty much compared to wiggling and doing more than wiggling.
mivey
Senior Member
By the other side I wasn't pointing at Rick in particular even though your quote had his name. His argument has been different from most of the others.
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