Why is residential wiring known as single phase?

[T.M.Haja Sahib]

No, this is incorrect. The DIFFERENCE, not the SUM of V1n and V2n should equal 240. V12 = V1n - V2n. It is really that simple.

Okay,your basis for taking the difference not the sum is based on

V12 = V1n - V2n or

V12 = V1n - (V2n)or

V12 = V1n - (-Vn2)or

V12 = V1n + Vn2

Here Vn2=-V2n=-V*sin(wt+180)=-[-(V*sin(wt)]=V*sin(wt).Also V1n=V*sin(wt).So the
two load voltages are in phase.

 

[T.M.Haja Sahib]

If the windings can be paralleled are they 'in-phase'? YES or NO

I think the discussion is reaching a crescendo.

 

[Besoeker]

Nope you changed the discussion. I agree V2n=-Vn2

But that is not what I asked about, I really and truly do not care how something appears, based on some absolutely irrelevant change in an arbitrary reference point.

I want a simple answer based on the actual construction of a specific transformer.
If the windings can be paralleled are they 'in-phase'? YES or NO

No need to shout, old chap!
Yes, they have to be in phase to be paralleled. I don't think that was ever disputed.
But you have already agreed that they are not connected that way for residential wiring.
It's overwhelmingly used as a series connection which results in 120-0-120 with the 120s being mutually displaced by 180 degrees when measured wrt the COMMON neutral.
I would call that different phases.

 

[T.M.Haja Sahib]

What's to interpret?
120Vdc is usually taken to mean mean.
120Vac is usually taken to mean root mean square.

Just common knowledge. At least for those in the electrical field.

Let me give a clue.

There are two values under each head and I am requesting with due respect to check your understanding about the differences between A.C and D.C Voltages with respect to those values.

 

[Besoeker]

Let me give a clue.

There are two values under each head and I am requesting with due respect to check your understanding about the differences between A.C and D.C Voltages with respect to those values.

Let me get this right.
You want to check my understanding of the differences between AC and DC?
Is that what you mean?

 

[jim dungar]

...Yes, they have to be in phase to be paralleled.

Wow a single, absolutely with no other possibility, answer.
I am not yet into the interconnection of the windings, I am trying to get agreement on the fundamentals of the winding construction and the terminal designations. You have stated the two windings are 'in-phase'. Can I assume you also agree this is because of the way the transformer has been fabricated?

Per standard industry practices, as we previously discussed the terminals on these winding are X1, X2 and X3, X4.
I am trying to to not get caught up with directions so I am trying to avoid the "-" sign, so with your permission I will use "~" instead,
and thus list the windings as X1~X2 and X3~X4.

Without knowing anything else about the transformer, except the simple the fact the windings can be paralleled, then we should say the voltage and current relationships of winding X1~X2 are equal to those of X3~X4?

 

[Besoeker]

Wow a single, absolutely with no other possibility, answer.

I'm an old fellow with a lot of years experience. Would you honestly expect me to dispute anything that obvious?

I am not yet into the interconnection of the windings, I am trying to get agreement on the fundamentals of the winding construction and the terminal designations. You have stated the two windings are 'in-phase'. Can I assume you also agree this is because of the way the transformer has been fabricated?

Already been agree.

Per standard industry practices, as we previously discussed the terminals on these winding are X1, X2 and X3, X4.

Yes. With X1 & X3 being the starts respectively.

Without knowing anything else about the transformer, except the simple the fact the windings can be paralleled, then we should say the voltage and current relationships of winding X1~X2 are equal to those of X3~X4?

The voltage measured between X1 and X2 would be in phase with that measured between X3 and X4 provided they wire measured that way round.
Without knowing the type of load on each, you can't say definitively that the currents will be so.

 

[rattus]

Okay,your basis for taking the difference not the sum is based on

V12 = V1n - V2n or

V12 = V1n - (V2n)or

V12 = V1n - (-Vn2)or

V12 = V1n + Vn2

Here Vn2=-V2n=-V*sin(wt+180)=-[-(V*sin(wt)]=V*sin(wt).Also V1n=V*sin(wt). So the two load voltages are in phase.

No. V2n is the load voltage not Vn2, and we measure the "difference in potential" between L1 and L2. We can do this with instantaneous values or with phasors. We cannot do it with RMS values.

 

[jim dungar]

The voltage measured between X1 and X2 would be in phase with that measured between X3 and X4 provided they wire measured that way round.

Again I am speaking strictly about two un-connected un-loaded windings. I am not talking about measurement reference issues. I am talking about electro-magnetics and the physical construction of the transformer.

Then would it also be correct to say, that based on the construction of the transformer and following industry standards for terminal identification; given identical loading, if current is flowing out of X1 then current would also be flowing out of X3 (remembering the windings are not yet interconnected)?

 

[jim dungar]

I'm an old fellow with a lot of years experience. Would you honestly expect me to dispute anything that obvious?

You no.
Others?

 

[Besoeker]

Again I am speaking strictly about two un-connected un-loaded windings. I am not talking about measurement reference issues. I am talking about electro-magnetics and the physical construction of the transformer.

You did mention current in your post #966.

Then would it also be correct to say, that based on the construction of the transformer and following industry standards for terminal identification; given identical loading, if current is flowing out of X1 then current would also be flowing out of X3 (remembering the windings are not yet interconnected)?

Quite.

 

[jim dungar]

You did mention current in your post #966.

I was trying to get establish the realtionship between the windings.

Quite.

Can I summarize this then as: the real world construction of the transformer directly impacts the relationship between its windings and if the individual secondary windings can be connected in parallel they must be "in-phase"?

 

[rbalex]

Pure spin.

Once again you demonstrate your refusal to accept subtle differences between terms; such as "in-sync" or "in-phase." If you wish to assert there is no essential difference between synchronism and phase because you can't tell the difference on your oscilloscope; that's fine, you're entitled to your opinion-you're simply wrong.

Just because you don't seem to know the "subtle" difference between definition and description, doesn't mean it's “spin” to say you only offer descriptions rather than definitions, nor is it “spin” to say those descriptions are compatible with the definitions of phase I have offered or accepted from rattus. I do recognize the inability to measure definition or description on your oscilloscope puts you at a severe disadvantage; I apologize.

In the context of our discussion, from Webster’s Collegiate Dictionary, 11th edition (the “official” NFPA dictionary for otherwise undefined terms:

Definition a: a statement expressing the essential nature of something

Description a: an act of describing; specifically: discourse intended to give a mental image of something experienced

​

(In your case, I suppose we should replace "mental" with "oscilloscope.")

​

The website these various definitions link to (merriam-webster.com) uses the same definitions as Webster’s Collegiate Dictionary, 11th edition.

If you wish to cite alternate relevant definitions, feel free. But you haven't done it yet.

Keep dreaming.

I guess I will - as long as you keep releasing rabbits.

 

[pfalcon]

Phase definition

Phase definition

Since we are starting all discussions from

Ideal sinusoidal 60hz Vac
|240| or |120|
One cycle described as "0<=T<360" permitting radians or grads when labeled. Permitting a symbol other than T when readily obvious or labeled.

Why don't we all just ignore all the subtle distinctions between Joe's dictionary, Pete's dictionary, etc and get back to:

When AN and BN referenced at N are traced then V_an and V_bn display as:
Classic waveforms where P_an = +|V| @ T=90 and P_bn = -|V| @ T=90

 

[Besoeker]

I was trying to get establish the realtionship between the windings.

Which had already been agreed.

Can I summarize this then as: the real world construction of the transformer directly impacts the relationship between its windings and if the individual secondary windings can be connected in parallel they must be "in-phase"?

I don't believe that the arrangement of the windings was disputed.

 

[jim dungar]

Which had already been agreed.


I don't believe that the arrangement of the windings was disputed.

Based on these unconnected windings, is there any other correct answer other than 'as built, they are in phase'?

Continuing this thought process, is it acceptable to say the physical construction of the transformer provides an absolute answer as to the relationship between unconnected windings?

 

[Besoeker]

Based on these unconnected windings, is there any other correct answer other than 'as built, they are in phase'?

Continuing this thought process, is it acceptable to say the physical construction of the transformer provides an absolute answer as to the relationship between unconnected windings?

This has already been agreed in posts 936, 963, 967 and 967.And probably quite a few others.

 

[jim dungar]

This has already been agreed in posts 936, 963, 967 and 967.And probably quite a few others.

Was not trying to be a complete pest. I just wanted common ground on the fact it is possible to have an absolute answer based on the physical construction of a transformer.

Mivey seems to disagree

Do you not realize what you are calling the "real world" is a relative concept?

 

[jim dungar]

This has already been agreed in posts 936, 963, 967 and 967.And probably quite a few others.

Sticking with this specific transformer:
Winding X1~X2 is in phase with X3~X4.
If we follow the industry standard interconnections, they can be interconnected as:
paralleled with X1&X3~X2&X4,
series with X1~X2&X3~X4

We still have not connected any loads, nor have we tried to measure any voltages. All we know is the physical construction of the transformer.
Does simply making either of these connections change the previously agreed upon 'in phase' relationship of the windings?

 

[Besoeker]

Was not trying to be a complete pest. I just wanted common ground on the fact it is possible to have an absolute answer based on the physical construction of a transformer.

Agreement on that has been established.