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.





You found one obscure white paper from a guy who lives in a place that
does not even use center tapped services and he said "split phase" so
you think that is the proper term.

Canada doesn't use center tapped? Maybe Clare can enlighten us, but I
thought they did. At any rate, the company sells power conversion products
into the USA and he did a lot more than just call it split phase, he
went through an analyis of it and how there are two 180 deg phases
present.

I don't know how Canadians talk and Clare is quick to point out they
do not use the NEC.
We are talking about accepted nomenclature for US based electrical
professionals. They have a different name for non metallic cable too.

The issue was you claimed the author of the white paper I cited lives
in a country that doesn't use center tapped transformers to provide
240/120, to try to discredit him and his explanation about phase,
split-phase, etc. So, apparently you conceded that Canada does use
center tap transformers too.

And no, we're not talking just about accepted nomenclature, we're talking
about how you analyze circuits and what's really there. I've said that
from my very first post here.





"Split Phase" is a type of motor, not an electrical distribution
method.

Go ahead and look like an unqualified homeowner if you want
but don't be shocked when electricians and inspectors start to just
roll their eyes and ignore you..

I am out.

And again, you just completely blew off the IEEE paper that I again
provided you with a link to. A paper written by a power engineer
with 40 years experience, presented at a power industry conference,
published by the IEEE. A paper that directly addresses exactly what
we're talking about.


Abstract:
Distribution engineers have treated the standard "singlephase" distribution transformer connection as single phase because from the primary side of the transformer these connections are single phase and in the case of standard rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Which now brings into focus the reality that standard 120/240 secondary systems are not single phase line to ground systems, instead they are three wire systems with two phases and one ground wires. Further, the standard 120/240 secondary is different from the two phase primary system in that the secondary phases are separated by 180 degrees instead of three phases separated by 120 degrees. What all of this means is that analysis software and methods must now deal with an electrical system requiring a different set of algorithms than those used to model and analyze the primary system. This paper will describe the modeling and analysis of the single-phase center tap transformer serving 120 Volt and 240 Volt single-phase loads from a three-wire secondary.

W. H. Kersting
Milsoft Utility Solutions, USA
W. H. Kersting (SM'64, F'89, Life Fellow 2003) was born in Santa Fe, NM. He received the BSEE degree from New Mexico State University, Las Cruces, and the MSEE degree from Illinois Institute of Technology. He joined the faculty at New Mexico State University in 1962 and served as Professor of Electrical Engineering and Director of the Electric Utility Management Program until his retirement in 2002. He is currently a consultant for Milsoft Utility Solutions. He is also a partner in WH Power Consultants, Las Cruces, NM.


And finally, I'd note I've given you and any other professionals here
the opportunity for several days now to give us your engineering definiton
of N phase power. No one can. Funny, it should be easy. Let me do
it for you:

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 covers it all. From single phase to an unlimited number of phases.
It's like the unified field theory being sought in physics, the holy grail,
only this one we have a complete definition and it's simple.

Single phase - covered
Two phase 90 - covered
Two phase 179 - covered
Two phase 181 - covered
Three phase - covered
Six phase - covered

Now, the only way the 240/120V service isn't two phase under that simple,
straightforward definition is if you explicitly put something in there
to rule it out. Science and engineering typically don't do that. We
have definitions or laws that fits all cases. Now from a historical perspective, from a "that's what it's always been called in the power industry perspective", it can be labeled whatever winds up being used, for whatever
reasons. It's like calling what you blow your nose with Kleenex or
tissues. It doesn't change the fact that it's a soft paper product made
from trees.

And if you have a better definition of N phase power, I'd be happy to
see it.