May I ask a question about the single vs two phase stuff

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LarryFine said:
No and yes.

It's not grounded for the purpose of measuring from. I've never seen a rule that one test probe must be connected to the grounded conductor. I place my solenoid tester's probes to various points when troubleshooting.
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it was rhetorical
that is why we ground it, and also to provide a gf earth return path for situations where the egc is not in the path and a true earth gf occurs
 
LarryFine said:
Because it isn't. It's one waveform that you're dividing into two of half the voltage by arbitrarily tapping the source in the center.

It's no different than using two 6v batteries in place of one 12v battery, and choosing to place a voltmeter probe on the jumper.

Now, if you choose, using the battery example with a meter probe on the jumper, to call that two sources at 180 degrees apart, I will still disagree, but I will also see your point.
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dividing into 2, creating 2 phases at 0 and 180 deg :happyyes:
 
LarryFine said:
Because it isn't. It's one waveform that you're dividing into two of half the voltage by arbitrarily tapping the source in the center.

It's no different than using two 6v batteries in place of one 12v battery, and choosing to place a voltmeter probe on the jumper.

Now, if you choose, using the battery example with a meter probe on the jumper, to call that two sources at 180 degrees apart, I will still disagree, but I will also see your point.
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wrong
the DC example is not applicable
it is 2 waveforms, 0 and 180 degrees, call it opposite polarity if you like, but that is a consequence of the wave being 180 deg out of phase, not a '-1'
 
jumper said:
And why is this a problem? It is a sine wave signal so of course it has a magnitude. No?
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I have no problem with that. Just with the statement that the inverse waveform of a 120V L1-N supply cannot be the negative of the first because we also call it 120V and not -120V.

Sent from my XT1585 using Tapatalk
 
Ingenieur said:
wrong
the DC example is not applicable
it is 2 waveforms, 0 and 180 degrees, call it opposite polarity if you like, but that is a consequence of the wave being 180 deg out of phase, not a '-1'
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What's the difference? Also, we are using mathematical expressions to approximate what we see in the world. The voltages are not a 'consequence' of the math at this level of physics. It's the other way around.

I still don't think I received adequate responses to my post 241.
 
jaggedben said:
What's the difference? Also, we are using mathematical expressions to approximate what we see in the world. The voltages are not a 'consequence' of the math at this level of physics. It's the other way around.

I still don't think I received adequate responses to my post 241.
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The difference is that at this point the discussion has moved beyond the battery analogy.

I actually use his exact post for a teaching tool.

But at this point the problem always goes back to this part of post 241 and the way we build it, measure it(pick a reference), and name it.

“It's been pointed out that in the physical world there are multiple ways to derive a 120/240V AC source with a waveform(s) resembling a sign wave.”

In short, same muddled mess as always and we have not even gotten into looking at the tranny from the primary windings perspective and the secondary noodle in power analysis.......
 
Ingenieur said:
it was rhetorical
that is why we ground it, and also to provide a gf earth return path for situations where the egc is not in the path and a true earth gf occurs
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The choice to earth the neutral and the choice to measure from only it are two different things.
 
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