Why is residential wiring known as single phase?

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Besoeker

Senior Member
Location
UK
Does the range example I have often cited, have a common conductor between the two loads? Is it the neutral of the voltages?
Fair point.
But would you call a hot a common?



Other than to say Vbn = -Vnb?
Don't believe I ever posted that. Others might have.

Actually I was trying to address the points I raised in a previous postings.

Although now that you bring it up. You posted a nice graph and current values for a 3-load circuit. I don't think I saw your 2-load results?
Would you like me to re-submit without the line to line load?
David and I discussed his results, which brought up the issue of a node with two currents entering but none leaving.
From my days in education all those decades ago, I seem to recall that it was often presented that way with the sum of the currents being zero per good old Gustav K.

Hundreds, going on thousands, of posts and I have yet to see a single one saying these circuits, like the rectifiers you are rightly proud of, cannot work. I said there appears to be a displacement based on the way you choose to reference your wiring (not the actual wiring itself). Choose a different reference and there appears to be no displacement. Are you saying my notations, showing 0? displacment, on your diagram, are incorrect?

Kind words, sir Jim. Without that 180deg displacement, they could not work.
 

Rick Christopherson

Senior Member
I'm also a moderately practical fellow.

To this:

Julybatch08042.jpg


in a weekend. Including the painting, the laminate floor, a new commode (not shown), the plumbing for it etc. The taps and waste for the basin were done the following weekend.

Simple point. I don't do just theory.
I would recommend a 15 gauge pneumatic nailer to help pull the baseboards tighter to the wall.

If you're curious what I do in my spare time, this took a little longer than a weekend. The engineering alone took a week, and the construction took about 3 months. Most of that time was spent waiting for the $6000 of custom hardware to come back from the machine shops. (And of course, it is electrical related. It is powered by a 3-phase (12-volt DC brushless) servo motor that I had to jury-rig controls for to interface with the PWM controller. :cool:)

TableComposite-sm.jpg
 
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T.M.Haja Sahib

Guest
I'm afraid it is your reasoning that went astray from the building.



It doesn't matter if 'N' is grounded or not - its' voltage is 0V. So is L1's, so is L2's, etc. Voltage is the electric potential difference between TWO points. Saying N has 0V is meaningless because you are only referencing ONE point is the system.



You are still missing that fact that a vector has MAGNITUDE and DIRECTION. You are ignoring the DIRECTION component. The voltage vector from L1 to N has the same DIRECTION as the voltage vector from N to L2. So if the voltage vector from L1 to N is 120<0V, then the voltage vector from N to L2 is also 120<0. The sum (not the difference) of these two vectors gives the voltage from L1 to L2. Vl1-n + Vl2-2 = 120<0 + 120<0 = 240<0.

It should also be clear that if the voltage vector from L1 to N has a value of 120<0V, then the voltage vector from N to L1 would be the reverse of it. In other words Vn-l1=120<180V, which is the same as -120<0V.

Do you say that voltage vectors V1-N and V2-N are acting simultaneously on the respective loads?
Are V1-N and V2-N instantaneous or RMS voltage vectors?
Do you agree that instantaneous voltage vectors are only relevant to the present discussion?
 
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T.M.Haja Sahib

Guest
I'm also a moderately practical fellow.

This:

Junebatch07027.jpg


To this:

Julybatch08042.jpg


in a weekend. Including the painting, the laminate floor, a new commode (not shown), the plumbing for it etc. The taps and waste for the basin were done the following weekend.
You may also have appeared in the above completed work with thumbs up..:D
 
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T.M.Haja Sahib

Guest
See post #227.
We alone, have used this arrangement for huge numbers of power electronic applications.
You are grossly mistaken.Whatever AC voltages you depicted there and elsewhere are all RMS values,not instantaneous.The present discussion is about instantaneous voltages and currents on 240V/120V single phase system and how that would lead to relevant RMS values of voltages and currents.........
 
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T.M.Haja Sahib

Guest
Don't you think I might might be more likely than you to know what we have built and shipped?
If so,please explain in brief how in phase instantaneous voltage and current, and out of phase instantaneous voltage and current are utilized in the operation of the device.
 

Besoeker

Senior Member
Location
UK
If so,please explain in brief how in phase instantaneous voltage and current, and out of phase instantaneous voltage and current are utilized in the operation of the device.
Hold on a minute......lets' back up a few......

You asked me what the circuits were.

I gave you this in post #288
See post #227 (which was the circuit arrangement).
We alone, have used this arrangement for huge numbers of power electronic applications.

To which you responded:
You are grossly mistaken.
So what exactly is it about my post #228 that you think justifies you accusing me of being grossly mistaken?

I can, of course, explain to you how the circuit works - after all, I designed it. But would there be any point my doing so if I am, in your opinion, grossly mistaken?
In short, would you believe me?
 
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T.M.Haja Sahib

Guest
So what exactly is it about my post #228 that you think justifies you accusing me of being grossly mistaken?
You mistook RMS values for instantaneous values and falsely asserted that 240V/120V single phase system is a two phase system on the basis of its RMS voltages designation 120V-0-120V and tried to justify it through your unrelated post #228.
 

Besoeker

Senior Member
Location
UK
You mistook RMS values for instantaneous values
I absolutely did not. In fact, you should have been able to determine that from the waveforms I posted.
So, I'm afraid you are mistaken and ought to withdraw that comment forthwith.

and falsely asserted that 240V/120V single phase system is a two phase system on the basis of its RMS voltages designation 120V-0-120V.
I have asserted that, for a 120-0-120 system, Van and Vbn are mutually displaced by 180deg. I continue to assert that simple fact.
 
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T.M.Haja Sahib

Guest
I have asserted that, for a 120-0-120 system, Van and Vbn are mutually displaced by 180deg. I continue to assert that simple fact.
By Van and Vbn do you mean instantaneous voltage vector values?
 

Besoeker

Senior Member
Location
UK
tried to justify it through your unrelated post #228.
Post #288 was a simple answer to your question "What are they?"
A simple statement of the facts as they are.
We have supplied huge numbers of PCBs with this 50V-0-50Vcircuit arrangement.
The two halves HAVE to be in anti-phase for it to work.
 
T

T.M.Haja Sahib

Guest
Post #288 was a simple answer to your question "What are they?"
A simple statement of the facts as they are.
We have supplied huge numbers of PCBs with this 50V-0-50Vcircuit arrangement.
The two halves HAVE to be in anti-phase for it to work.
Please do not try to mislead,The center tapped transformer in your post # 288 is entirely different from the center tapped transformer under discussion here in that your transformer secondary windings were wound in the opposite direction,one clockwise and the other anticlockwise so that 180 degree shift is possible.
 
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