So - how many phases?

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So - how many phases?

  • 1

    Votes: 25 89.3%
  • 2

    Votes: 0 0.0%
  • Other - and I'll explain why

    Votes: 3 10.7%

  • Total voters
    28
  • Poll closed .
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ritelec

Senior Member
Location
Jersey
I'll take what's behind door number one Bob...........................A New Maserati !!!!!!


What the hey...........went for other as it was noted "and I'll explain why".


????
interestingly watching.
 
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mivey

Senior Member
I'll take what's behind door number one Bob...........................A New Maserati !!!!!!


What the hey...........went for other as it was noted "and I'll explain why".


????
interestingly watching.
Well join the club. I do not think the OP was specific enough with the question so that leaves room for different interpretations. Mine is based on the output voltages and this post #847 has my graphic illustrating why there is not one simple answer. The question "how many phases" has too many undefined parameters.

The simple non-technically correct answer is one since it is a single-phase transformer. The simple technically correct answer is up to two if we make some simplifying assumptions and consider simple voltages. The complicated technically correct answer is many if we consider the current phases as well.
 

rbalex

Moderator
Staff member
Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
FWIW my analysis (1) is summarized here as Post #888.

Basically, there are three categories of thought:
  1. Those that just don’t know why it is “single-phase,” and simply accept that's what we commonly call it.
  2. Those that essentially consider "in-sync" and "in-phase" synonymous and it is dependent on how it's measured or pictured. “We only call it ‘single-phase’ because 'two-phase' is already taken, but there are really at least two phases.”
  3. Those that believe that "in-sync" and "in-phase" are distinct concepts and there is a uniquely applicable underlying historic and physics basis for the term "single-phase" that is independent of how it’s measured.
 
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rbalex

Moderator
Staff member
Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
I did not assume everyone agreed with it. It was the definition I used to go along with my response. My improper use of the word stipulation did not reflect my intent.
Yeah, I'll give you credit for that - sorry I acknowleded this so late. Even "cutting & pasting" takes a lot of time, especially when inserting math terms in other threads.
 

Smart $

Esteemed Member
Location
Ohio
... The simple technically correct answer is up to two if we make some simplifying assumptions and consider simple voltages. ...
Following this nonsensical "guideline", a US standard 3? 4W wye secondary transformer output has twelve phases. :lol:
 

mivey

Senior Member
Following this nonsensical "guideline", a US standard 3? 4W wye secondary transformer output has twelve phases. :lol:
Talk to Besoeker, he can help you understand how to get more than three phases from a three-phase supply as he does it all the time in real-world applications.
 

Smart $

Esteemed Member
Location
Ohio
Talk to Besoeker, he can help you understand how to get more than three phases from a three-phase supply as he does it all the time in real-world applications.
I'm well aware of how to manipulate connections, equipment, and devices to get more than three phases (all twelve, and more if I want). However, what we are discussing is predicated by conventional naming schemas. There is no need to go into it further, for it is most doubtful you will sway the multitudes accepting that convention. I know you understand that. For what reason(s) you continue to rehash the issue, I haven't a clue... nor do I care [to know].
 

mike7330

Senior Member
Location
North America
OK, I'm done saying all I have to say on the matter. Rhetoric may continue as normal.

OK, I'm done saying all I have to say on the matter. Rhetoric may continue as normal.

"OK, I'm done saying all I have to say on the matter. Rhetoric may continue as normal"

Oh How true a statment!!!!
 

ritelec

Senior Member
Location
Jersey
Can I change my answer to 1 phase?




LOL...............naugh ............I'll stick with "other".


What's behind door #2 Bob?

A genuine simulated Indian beaver coat...............
see they don't have beavers in India so they have to simulate them.
 

ritelec

Senior Member
Location
Jersey
tick tick tick tick..............

What's behind door #3 Bob?


A personally autographed picture of Randy Mantooth, and Bob Dylan's new unlisted phone number....



tick tick tick tick..............
 

mivey

Senior Member
I voted zero for the reasons stated in a prior post (no alternating wave present = no phase). I also noted that the transformer can be a source for more than one phase for the reasons also stated in a prior post (using the technically-correct definition of phase, more than one phase can be present)

But for the record, I am not a proponent of changing the transformer label. It is a single-phase transformer.

A simple labeling rule could be: "Only voltage phases will be considered for labeling purposes, and multiple phases that can be paralleled or that are opposing pairs will be counted as one phase in total."



The reason for calling it a single-phase transformer was based on work done back in the 1860's and is the following:


Combining two available forces from a center-tapped transformer produces a larger resultant force in most circuit applications when the two forces are in-phase, in-series. These combined forces will act as one combined larger series force so we call it single-phase. A more descriptive label would be "series additive single-phase".

The "single-phase" label is not because it is a pure single-phase system (i.e. a two-wire source) but that the two smaller combined phases result in a larger single phase. Considering one phase to be the return of the other (possible since they are opposing pairs) equates the combination to a larger single-phase system, but it is still a system containing two smaller phases. Both systems can be produced by one center-tapped winding, in the same manner that the quadrature, or four-phase system, can be produced by two center-tapped windings.
 

realolman

Senior Member
....A simple labeling rule could be: "Only voltage phases will be considered for labeling purposes, and multiple phases that can be paralleled or that are opposing pairs will be counted as one phase in total."

I think PPE is needed to read that:)
 
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