On Saturday, July 28, 2018 at 1:42:19 PM UTC-4, wrote:
On Sat, 28 Jul 2018 09:52:57 -0700 (PDT), trader_4
wrote:

On Saturday, July 28, 2018 at 11:32:53 AM UTC-4, wrote:
On Sat, 28 Jul 2018 07:50:14 -0700 (PDT), trader_4
wrote:

On Friday, July 27, 2018 at 5:40:53 PM UTC-4, wrote:
On Fri, 27 Jul 2018 12:45:40 -0700 (PDT), trader_4
wrote:

On Friday, July 27, 2018 at 12:26:34 PM UTC-4, wrote:


I defined phase as in single, 2 or 3. You just chose to ignore it.

You gave a definition that is historical, not from an engineering
perspective and you didn't define anything more than 3. You would
think if it's so simple, someone could define it for N phases.
And then you refuse to answer the obvious questions
that even a student would ask a teacher. According to you, two
phase was 90 deg over four wires. OK, so, if it was over 3 wires, using
one shared neutral, would two phases still be present? Now I change
the phase to 179 degrees or 181 degrees, are there still two phases?
Yes? No?

Why then are there not two phases present when it;s 180? The answer
of course is that there still are two phases, it just becomes a less
interesting case.

You look at a system from end to end, not any small segment.
This is a single phase system.

Inability to answer the simple relevant questions a student would
ask a teacher noted.

I answered the question several times. I just told you what
electricians and inspectors call the service you have in your house.
If you can't understand that and need some other rationalizations to
explain what you have, go for it.
I don't care anymore.

No, you have not answered the simple specific questions.

You say that what was called two phase power 100 years ago when it
existed, was in fact two phases. You said it was over 4 wires.
I accept that. So, here are the simple questions a student might
ask a teacher:

If it were on 3 wires instead of 4, with a shared neutral, would there
still be two phases there?

It is actually on 5 wires and there is a neutral there.
Two phase does still exist in some archaic industrial equipment in the
North east the last I heard.

If yes, then how about if I change the phase angle to 179 degrees or
181 degrees, would there still be two phases?

How did you get 181 degrees?


Why does that matter? The electrons in the cable don't care if
the other phase at some deg of separation was generated from another
winding on the same shaft, another generator that you somehow managed
to keep in perfect synch, or via an entirely electronic method, eg
synthesize it electronically like you would with a UPS.


N Phase Power - A power delivery system that uses N related voltage sources,
that are periodic waveforms of the same frequency, differing only in
phase.

That simple engineering definition neatly covers it all, one, two, three,
N phase.



If it comes from a separate system, yes
it would be 2 phase.

Separate system? Where did that requirement come from? Three phase
AFAIK is generated from 3 windings on the same shaft, separated by 120 deg.
Do diesel 3 phase generators have 3 motors? What's does a "separate system"
even mean? They can't be really separate and be locked at a fixed phase separation.




If yes, then why if I change it to 180, are there no longer two phases?

The problem is you did not change it to 180. You just sampled a
different place on the same single phase wine wave.

Of course I'm changing it to 180. I take your old 90 deg two phase
generator that you say was two phase. I move the second winding from
90 to 179. I think you're saying that's still 179. So, now I shut it
off, rotate the one coil 1 more deg, it's at 180. I start it up again,
is there now just one phase simply because it's 180, not 179?







What did you think of my definition of N phase power?

There is 1, 2 or 3 phase power in the US distribution system. Nothing
else. I do understand you could have circuits operating at any number
of different phase relationships but that will be in the electronIC
world, not US power distribution.

Which doesn't change how electrons behave or how systems are analyzed.
What you choose to call it does not change what is really there. You
also seem to dismiss the existence of Electrical Engineering, which
is the field of expertise that includes power
engineering, it's everything that flows out of Maxwell's Equations,
from a generator to radio waves. That IEEE Fellow that wrote the paper
analyzing exactly what we're talking about that you continue to dismiss
is one of them.



It is a different culture with words
that are used differently. (I have lived in both) That is why you can
find very well credentialed people who do not speak "electrician". I
bet they think a "city hub" is a bus station and a "hickey" is
something you don't want to see on your daughter's neck. ;-)

I gave you my definition of N phase power that neatly covers it all,
from one phase to N phase. I'm still waiting for your general definition,
that covers and explains the differences, as opposed, to relying on
"that's what we call it as a definition". I said in the first post I
would not *call* our residential power 240/120 two phase. I don't see
anyone doing that either. But electrically that is what you have with
a center tapped transformer. It behaves as, looks like and is two
voltage sources that are 180 deg out of phase with each other that
share a neutral.