On Tuesday, September 10, 2019 at 3:36:48 PM UTC-4, Joe W wrote:
On 9/9/19 4:28 PM, Ralph Mowery wrote:

[snip]

I don't intend to get into a discussion over this, Just wanted to point
out that by definition there is/was 2 phase in a few parts of the US.

That describes a 2-phase system (phases 90 degrees apart, and I don't
think anyone here disagrees with that. That they do disagree with is
that being 2-phase keeps anything else from being 2-phase. "2" and
"phase" are WORDS, and not restricted to a single instance.

It does not matter what anyone says, there is a certain definition
for 2 phase.

And that isn't it. It is an EXAMPLE of a 2-phase system.

It's as if the first truck you ever saw was a propane delivery truck, so
you think dump trucks can't really be trucks.

[SPAM snipped]

Exactly. And again, since no one will attempt to give a definition of
N phase power, I'll give you what I think a sound definition is:


A power delivery method utilizing N sources that are periodic,
of the same frequency, that differ in phase.

And then it becomes where do you look, what are you analyzing.
If one looks at the primary
side of the transformer, then clearly there is only one phase.
However if you look at the secondary side, the three wires going into
the house, then you have two sources, ie the the two halves of the
transformer that are 180 deg out of phase with each other.
Which is what that IEEE paper is about, how you have to treat it as
such to analyze it. For example, if there is reactive loading on
one side of the transformer, purely resistive loads on the other,
then the voltage and current waveforms on one side can have a
phase difference from the other side of the same transformer.
That is what the professor was pointing out, in terms of how it has
to be treated and analyzed.