Two phases or not?

[Jamie]

Nope, single phase.

The definition of "more than one" phase is a difference
of something other than 0 or 180 degrees.

With either 2-Phase (the old 90 degree system) or 3-phase
(current 120 degree system) the phases can NOT be generated
with a simple transformer. They are generated by multiple
alternators mounted on a common shaft.

With a single transformer, and a center tap, you have two
voltages, in phase, that add together.

It's single phase.

Jeff

Big JOKE!

You fail.

 

[Mark Cross]

A disagreement arose
thereafter about whether a center-tapped transformer actually delivers
two separate phases of electricity or not.

So, what do y'all say?

Formally, yes, there exist two phases set apart 180º. But formally also that
is never called a "two-phase system".

Reasons:
1.- In polyphase system there is an usual understanding that phases are
different when you can not get the other phase by simple means other than
using transformers (or transformer arrays). In a 3 Phase system, there is no
way to get a phase 120º away by adding, subtracting or switching cable ends
of one phase. In a true two phase system, be it a three wire part of a 3
phase system or the Niagara example, there is no way to get the other phase
(120º or 90º) by playing with the connections. In a "split phase" system,
the 180º phase is equal (in a balanced system) to the other one by just
exchanging the "hot" and "ground" wires.

2.- The phase supplying the power to the "split-phase" winding in the
secondary of home transformers is only ONE, there is no way to get more than
ONE phase out, even if formally the secondary winding could be measured
reversing the leads and appear as the negative value (hence the 180º figure)
Those two windings of the "split-phase system" are connected in such a way
as to provide a total voltage of 240V but could have been connected in
parallel to provide the double of current in one phase at 120V. Such
parallel connection would produce a "short" and high currents if in fact the
two windings were being driven by two distinct phases no matter what games
you play with the wire ends.

So, that's why any power engineer will raise an eyebrow if you address such
system with the clearly incorrect term of "two-phase system".

 

[Phil Allison]

"Wild_Bill"

These comments are logical and correct representations of the power system
that most of us use. For single phase motors, a 120VAC motor is a
single-phase motor, just as a 240VAC motor is referred to as a
single-phase motor, not a 2-phase motor because it's using 2 hot lines.

** Massive straw man fallacy.

Why am I not surprised it comes from a fucking TOP POSTER !!




..... Phil

 

[David Nebenzahl]

These comments are logical and correct representations of the power system
that most of us use. For single phase motors, a 120VAC motor is a
single-phase motor, just as a 240VAC motor is referred to as a single-phase
motor, not a 2-phase motor because it's using 2 hot lines.

This issue is one that just gets argued endlessly by amateurs and intellects
to no end.. essentially a waste of useful time on an issue that's widely
misunderstood for all the wrong reasons.

I disagree entirely. Yes, in this case it's a semantic debate--what I
contend is actually 2-phase power (120-0-120 derived from a
center-tapped transformer) is not *called* that by the electric power
industry. It is, nonetheless, truly two phase power.

I think it's important because the idea of phases in electrical power is
an important one, even to a simpleton like the average electrician,
never mind the EE.

Example: if you're going to wire an Edison circuit (where two hots from
different phases, meaning different sides of the distribution panel, are
wired with a common neutral), you ought to understand electrical phases,
especially the consequences of two phases 180° apart. After all, that's
how the currents from the two sides cancel each other. Failure to grasp
such principles can, and do, lead to real-world consequences like
building fires.

Pick the issue apart just for sport, if you like, but the majority of
domestic power supplies are single-phase.. period.

Look anywhere you can for a New 2-phase motor.

Who said anything about a 2-phase motor? Nobody, so far as I can tell.

I'm saying that the ENTIRE DOMESTIC POWER SUPPLY FROM THE SECONDARY OF
THE POWER COMPANY'S TRANFORMER is 2-phase. Once you plug in a 120 volt
anything, or even many 240 volt anythings, you're only using one phase.
Sheesh.

The only individuals that would be describing a new motor as a 2-phase motor
will be some misguided trainee or someone taking advantage of your stupidity
of asking for one.

Again, where did this straw man come from?

Please notice that because of your non-standard top posting, any
previous replies have been cut off. Please do what 99% of others do here
and bottom post.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

 

[Jamie]

I disagree entirely. Yes, in this case it's a semantic debate--what I
contend is actually 2-phase power (120-0-120 derived from a
center-tapped transformer) is not *called* that by the electric power
industry. It is, nonetheless, truly two phase power.

I think it's important because the idea of phases in electrical power is
an important one, even to a simpleton like the average electrician,
never mind the EE.

Example: if you're going to wire an Edison circuit (where two hots from
different phases, meaning different sides of the distribution panel, are
wired with a common neutral), you ought to understand electrical phases,
especially the consequences of two phases 180° apart. After all, that's
how the currents from the two sides cancel each other. Failure to grasp
such principles can, and do, lead to real-world consequences like
building fires.



Who said anything about a 2-phase motor? Nobody, so far as I can tell.

I'm saying that the ENTIRE DOMESTIC POWER SUPPLY FROM THE SECONDARY OF
THE POWER COMPANY'S TRANFORMER is 2-phase. Once you plug in a 120 volt
anything, or even many 240 volt anythings, you're only using one phase.
Sheesh.



Again, where did this straw man come from?

Please notice that because of your non-standard top posting, any
previous replies have been cut off. Please do what 99% of others do here
and bottom post.

Don't waste your breath. it's not worth the effort.

Knowing that you understand it should be enough..

And by the way, I was looking at a 3 wire motor today, 2 phases of 180
apart with CT to operate it (3 wire motor). It was attached to a gear
box and only ran one direction, but you could use it as a stepper
(servo) or full out run. Most likely some custom motor for an application.

Jamie

 

[JW]

Look at his website before you concede.

http://webpages.charter.net/jamie_5/

Ack! I almost went blind after seeing that pic on the right.

 

[David Nebenzahl]

<SNIP> And you have started another arguement here. haha..

Honestly this is a question that I have always had, and can't understand why
it isnt called 2 phase. Unless there is something to the picture I am
unaware of.

This qustion will enevetably be debated to the end of time. It is kind of
like discussing poloitcs or religion..

Well, it really shouldn't be like that. I mean, look, we're discussing a
well-known, measurable phenomenon. The output of the center-tapped
transformer can be demonstrated to supply two separate and distinct
phases. Hell, hook up two 'scopes and see what they show.

It's just that the 'lectric-heads--the lunks who install distribution
panels and such--won't let us *call* it "2-phase" for several dubious
reasons. Doesn't change the fact that it IS two-phase power. That's what
I'm getting at. I'm not trying to force anyone to change their
terminology or give up their superstitious beliefs; I know that that's
futile.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

 

[David]

Unfortunately. Maybe we should more generic terminology to

describe this. There is a difference in the phase of the two
legs off of a center tapped transformer. This can not be
argued. Anyone who argues so can go hook up a couple scopes for
themselves as you suggested.

Maybe the confusion exsists because of the nature of two
seperate phase (split phase) power vs 3. Correct me if I am
wrong, but any device requiring 240V could be powered by 2 legs
of a center tapped 7200V==>120V N 120V transformer or could be
powered by a 7200V==>240V transformer with the same results.

That said Im sure someone will tell me why my theory of why
this is a confusion is wrong..

- Mike

|Hmm.. I must have not drank my coffee yet when I wrote this.. 3
phase would
|operate the same way therefore making this all bunk.

Actually three phase service from the power company with the
phases 120 degrees apart, would work differently. In a 'Y'
connection if the voltage between the phases were X volts, the
voltage from one phase to neutral would be x/sqrt(3) rather than
x/2 as is the case with a center tapped transformer.

David

 

[Phil Allison]

"Bob AZ"

The problem seems to be that after all this dialogue, that so many of
the responders simply don't stick to the basic premise that different
phases by definition have timing differences.


** More total nonsenese.

Sine waves of the exact same frequency and amplitude can ONLY differ only in
phase.

A 180 degree phase difference is as good as any other.


.... Phil

 

[Fred McKenzie]

Sine waves of the exact same frequency and amplitude can ONLY differ only in
phase.

A 180 degree phase difference is as good as any other.

Phil-

I have a flashlight powered by a two-phase system - two D cells. It
certainly fits your criteria. Its power system can also be considered
AC, since DC is just AC with frequency equal to zero.

Facts are no deterrent to a persistent troll!

Fred

 

[Phil Allison]

"Fred McKenzie"

"Phil Allison"



I have a flashlight powered by a two-phase system - two D cells.

** Nuh - that is DC, you pathetic troll.

It certainly fits your criteria.

** Nuh - not one of them.

Its power system can also be considered
AC, since DC is just AC with frequency equal to zero.

** Just like white is the same as black with no lights on.

Facts are no deterrent to a persistent troll!

** Just like reality is no deterrent to a lunatic.

Did someone leave the door open at the asylum today ??



...... Phil

 

[Meat Plow]

"Fred McKenzie"


** Nuh - that is DC, you pathetic troll.




** Nuh - not one of them.




** Just like white is the same as black with no lights on.




** Just like reality is no deterrent to a lunatic.

Did someone leave the door open at the asylum today ??

I'd make a comment here but it is against my new year's resolution.

 

[Jamie]

Having a couple of decades experience in servicing/repair of commercial
and consumer electronic equipment and additional training and experience
in industrial site experience (both electrical and electronic circuits),
I have never seen descriptions or designations stated as 2-phase, for
any type of transformer.

Or: Hey bub, you gotta single-phase-in, 2-phase-out transformer?

But I have seen and used transformers with multiple taps, on both pri
and sec sides.
The number of taps on either side of a single-phase transformer don't
change the output(s) to 2-phase, regardless of how many there are (pri
or sec side).
Monophase sounds odd, like it's not related to electricity.
How about uniphase? Yep, found an example (and diphase) used in a book c
1905.
Electricity In Every-day Life Edwin J. Houston PhD. You know that's
gonna be interesting just because it was authored by a PhD.

You still lose:

You don't seem to know the difference between circuits and phase
angles..

Typical residential hack electrician..

I hope you don't ever decide to move in to electronics, you'd be in a
world of shit.

 

[Jamie]

Phil-

I have a flashlight powered by a two-phase system - two D cells. It
certainly fits your criteria. Its power system can also be considered
AC, since DC is just AC with frequency equal to zero.

Facts are no deterrent to a persistent troll!

Fred

What are you a fucking moron?

 

[Phil Allison]

"Jamie" = radio ham KA1LPA

Fred McKenzie = radio ham K4DII


What are you a fucking moron?

** Yep - Fred is another radio ham.

K4DII
Frederick M. McKenzie
2867 EPP Bivings Drive
Titusville, Fl 32796



...... Phil

 

[Phil Allison]

"Jamie" = radio ham KA1LPA

Fred McKenzie = radio ham K4DII
Look Phil, I may not agree with avery thing you say, but at least
I am supporting you in this debate...

** Yawnnnnnnn....

And please don't use amateur operators as a signification of
stupidity..

** Shame that so many radio hams on usenet prove themselves to be the
biggest trolls, trouble makers and blow hard bullshit artists ever.

Damn shame about that.



..... Phil

 

[Jamie]

"Jamie" = radio ham KA1LPA




** Yep - Fred is another radio ham.

K4DII
Frederick M. McKenzie
2867 EPP Bivings Drive
Titusville, Fl 32796



..... Phil

Look Phil, I may not agree with avery thing you say, but at least
I am supporting you in this debate...

And please don't use amateur operators as a signification of
stupidity..

You can't fix stupid, It has no classification.

And admit it Phil, you just wish you were a HAM!

Watch and Weep!

Jamie

 

[Phil Allison]

"Jamie" = radio ham KA1LPA

And please don't use amateur operators as a signification of
stupidity..

** Shame that so many radio hams on usenet prove themselves to be the
biggest trolls, trouble makers and blow hard bullshit artists ever.

Especially YOU.

Damn shame about that.




..... Phil

 

[Jamie]

"Jamie" = radio ham KA1LPA



** Yawnnnnnnn....





** Shame that so many radio hams on usenet prove themselves to be the
biggest trolls, trouble makers and blow hard bullshit artists ever.

Damn shame about that.



.... Phil

Oh, I didn't know you were a ham yourself ? That would explain
why you have such animosity towards us, you speak from experience.


--... ...-- ...

Thou sayest, "Keep the brother hood together"!

Jamie

 

[Jamie]

"Jamie" = radio ham KA1LPA






** Shame that so many radio hams on usenet prove themselves to be the
biggest trolls, trouble makers and blow hard bullshit artists ever.

Especially YOU.

Damn shame about that.




.... Phil

Making assumptions like that about some one you know absolutely
nothing about, isn't very good character on your part. It just goes to
show how much of an ignoramus one could be, you for example.

Now, I understand your dilemma. I am forced to communication with
people of your type, every day. That does not mean I have to like it
how ever, it's a requirement I must adhere to.

Could it be these so called "Trouble Makers" as you call them are just
making you feel like you have too much competition ? I am sorry that
"we Amateur Operators don't kneel down and kiss your feet".

Jamie

P.S.
It's not nice trying to make yourself look better by devaluing others.

hint.