On Thursday, August 2, 2018 at 1:17:28 PM UTC-4, wrote:
On Thu, 2 Aug 2018 09:33:11 -0700 (PDT), trader_4
wrote:

On Thursday, August 2, 2018 at 11:46:38 AM UTC-4, wrote:

Again, that's why it's TWO voltage sources coming from the TWO halves
of the transformer and why it looks like, acts like and is two voltage
sources that are 180 out of phase or of alternate polarity, which is
the same thing.

so the problem here is the power engineer guy looks at the two signals that come off the pole into your house that are 180 deg apart and/or opposite polarity and in his mind these are ONE phase because he knows they were both derived from ONE phase of the 3 phase grid system and one is just inverted polarity of the other.

OK that is a valid view.


the signal engineer looks at the same two signals coming off the pole that are 180 deg apart and says, these are two sine waves that are 180 deg phase so it is TWO phases.

This is also a valid view.

Lets have a beer.


mark

I'm good with that. It's consistent with what I said in my first post.

The problem is you are bring audio thinking into a power scenario.

You know, I kind of saw that coming. Mako said "signal" and I let it go.
I didn't want to be overly critical or accused of nitpicking and I thought
he has it about right. But it isn't an issue of from a signal prospective.
It's basic electrical engineering circuit analysis 101.

You seem to think that there is one way of doing circuit analysis
for power circuits and another for audio circuits. It's all one and the
same thing. I gave you my circuit model using two 120V voltage sources
that are either 180 deg out of phase with each other or connected with
opposite polarity, same thing. That is your 240/120 service and it could
come from a transformer, be synthesized from a battery, or just exist on
a piece of paper. It doesn't matter, it defines what's there and it's
all you need to know.





I would even contend that the audio guy would just call this a push
pull amp on one phase. The other stereo channel would be the other
phase. (hence "phasing" speakers)

The audio guy would hook up his scope ground to the ground on his audio
system and take a look at the phase relationships. When you do that in
your house, connect the scope ground to the house neutral/ground,
what do you see? TWO 120V voltage sources that are 180 deg out of phase
with each other. That explains why you can't randomly parallel any
two receptacles. It explains how you get 240V from one hot to the other.
I don't need to go outside, look for a transformer, talk about ends of
transformers. It doesn't matter if that service came from a synthesized
source powered by a car battery. What's there is what defines what you
have. Knowing what I just stated, and how many amps I am allowed, is
all I need to know to design with it, to use it.