On 7/24/2018 9:53 AM, trader_4 wrote:
Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?

The transformer for my house has a single phase input.Â* The output of the transformer is single phase as well.Â* I don't have a two-phase generator on my utility pole.

On Tuesday, July 24, 2018 at 11:28:39 AM UTC-4, Bubba wrote:
On 7/24/2018 9:53 AM, trader_4 wrote:
Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?

The transformer for my house has a single phase input.Â* The output of the transformer is single phase as well.Â* I don't have a two-phase generator on my utility pole.

There you have it, typical. Instead of responding to the simple questions
that go to the heart of the matter, just diversion. Others can note that
I responded to your oscilloscope connection question. Note that I also
gave you an opportunity to define for us what makes a system one phase,
two phase, N phase and then explain why residential doesn't meet the
definition of two phase. If you can't define it, then it becomes
arbitrary. Which is kind of what I and the moderator at the forum said,
it's just semantics.

On 07/23/2018 09:01 PM, wrote:

[snip]

Can you take your 2-of-3 phase and connect directly to a heat
element ? like the home 230 volt oven or clothes dryer ?
John T.

That sounds like how you get 208V.

208V is the sum of two 120V that are 120deg out of phase.

240V is the sum of two 120V that are 180deg out of phase.

480V is the sum of two 277V that are 120deg out of phase.

On Tue, 24 Jul 2018 02:45:45 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 10:14:18 PM UTC-4, wrote:
On Mon, 23 Jul 2018 17:47:02 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 8:24:43 PM UTC-4, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you? I really didn't expect I'd be waking anyone up by responding to a 7 year old post.

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

I even found a presentation a power industry engineer made at
a conference where he made the case that to correctly analyze a split-phase
system you have to treat it like what it is, a system with two phases.

The other argument is that if I start with a 3 phase system going into
a building, everyone agrees that there are 3 phases there, right? You can see
them on an oscilloscope. Now let;s remove one. How many phases now?
Two. Now instead of the phases being 120 apart, let's move one so that
they are 180 apart. How many phases now? Two. And if you look at it on a
a scope, it looks exactly like a split-phase gsystem going into the
same building and it behaves exactly like it. Electrically you can't
distinguish one from the other, they are the same thing.

That's my case, others will probably draw different conclusions.

There is single phase, 2 phase (that I doubt anyone here has ever
seen) and 3 phase. If you only use 2 legs of a 3 phase circuit, it is
single phase.

You have to start with the electrical engineering
definition of phase. It's simply the relationship between two periodic
waveforms. That's how we got the term three phase power to begin with.
It's based on the fact that the power is being generated as three separate
waveforms which are separated by 120 degrees.

Here is a good discussion going back and forth:

https://forum.allaboutcircuits.com/t...-phase.105861/


I agree with Wbahn, the group moderator there, he's saying it's about semantics.
And note whenever anyone is challenged as to why it can't be called two phase,
it all falls back to arguments, like "but two phase was 90 deg phase difference
and it doesn't exist anymore". When challenged along the lines of how you
define phase, why if you change 90 to 180, which is just one of the many
possibilities, it suddenly can't be called two phases anymore, they have
no electrical engineering answer, no definition, it's just that they
say it isn't. Change the phase angle
from 90 to 95, would it still be two phases? Why when it reaches 180 is
it no longer two phases? When it's at 185, would it be two phases again?

The argument Wbahn makes about a single shaft generator, instead of
supplying 3 phase, make one that supplies 2 phases, at the 90
deg if you like. Two windings, differing by 90 deg, supplying two
hots with a common neutral. Would that be two phases? If not,
why not? And if yes, then why isn't it two phases if I change the
phase angle to 180? If you agree that there are two phases still
there, then that is indistinguishable from the split-phase service
that enters your house. It's all about semantics and you have to
start with the definition of phase. Phase is simply the relationship
between two periodic waveforms.



Here, from MIT, an introduction to power systems, where they start out
with the simple case of a power system with two phases.
Note it's only about two voltage sources connected to two
loads, with two voltage sources that can be at any phase angle.
Nothing about where the voltage source originated from or what the phase angle
is. Nothing about magic happening at 180 degrees, where it's no longer
a two phase system. It's the completely general electrical engineering
case of what defines a two phase power system and how you analyze it.

https://ocw.mit.edu/courses/electric...061S11_ch3.pdf

Make those two voltage sources be the two sides of the transformer on the
pole at your house and it;s the split-phase service that serves your house.







Where you ground that does not change the number of phases.
In fact 3 phase center tapped delta is just your regular single phase
center tapped transformer connected to a delta primary with another
transformer (or two) providing the 3d phase.
OTOH if you corner grounded that delta you would have 2 (hot)
ungrounded conductors and a neutral with 2 pole breakers but it is
clearly still 3 phase.
Two phase is a totally different breed of cat with 2 phases (4 wires)
90 degrees out of phase. This will usually be 2 transformers center
tapped with the center taps grounded (5 wire).
Split phase is a type of motor winding, perhaps the most common for AC
compressors and other applications that use a start capacitor and no
run capacitor. The "phase" is "split" by a start winding 90 degrees
out of phase with the run winding.

How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.


It is single phase. There is only one secondary winding derived from a
single phase primary. The fact that you center tap that winding and
ground that tap does not magically add a phase.
I suppose the unknowing can call it anything they want but
professionals call your typical home service 120/240 single phase.

If I used your logic, a string of Christmas tree lights is "100 split
phases" because I would see a separate little 1.2v wave form across
each of the 100 bulbs on a scope and each one would be 180 degrees out
of phase from the bulb on the other side of the common lead on the
scope.

On Tue, 24 Jul 2018 06:29:01 -0400, Ed's Electric
wrote:

On 07/23/2018 08:24 PM, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?

OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you?

No, professionals call it single-phase.Â* Unless you want people to think you voted for Hillary, you should use the proper terminology.




;-)

On Tue, 24 Jul 2018 04:05:27 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 6:29:06 AM UTC-4, Ed's Electric wrote:
On 07/23/2018 08:24 PM, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?

OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you?

No, professionals call it single-phase.Â* Unless you want people to think you voted for Hillary, you should use the proper terminology.



Guess this manufacturer of panels, a former GE subsidiary, isn't professional?


http://www.geindustrial.com/products...ngle-phase-usa


PowerMark Gold* Single Phase - USA

PowerMark Gold - Single Phase - US

Homesphere

This product qualifies for HomeSphere** builder incentives.



PowerMark Gold load centers lower your costs by making installation faster and easier, increasing application flexibility and reducing inventory requirements. At the same time, they deliver obvious and significant advances in design, function and quality.
Features and Benefits

40-225 Amps main breaker
2 - 42 feeder circuits
22kAIC main breaker, series rated 22/10
Sturdy copper bus and galvanized box increase durability and reliability
Reduces total cost through faster, easier installation; enhanced application flexibility; and reduced inventory requirements
Solid neutrals for quick, easy, secure terminations
Available with white front



Or Square D:

Are I-Line panels available as single phase?
Issue:
Does Square D offer I-line panelboards in 1-phase?

Product Line:
Distribution panelboards

Environment:
I-line panelboards

Cause:
Product features.

Resolution:
Yes. Order a standard I-Line panel and only order breakers that are phased A-C.


Or Siemens?


https://w3.usa.siemens.com/powerdist...01-ALL-web.pdf

C o n t e n t s
Load Centers
Catalog Numbering System 1-2
Siemens PL and ES Series Load Centers„¢ Introduction 1-3
WireGuide„¢ Load Centers and Breakers 1-3
PL Series Load Centers Features and Product Offering 1-4 €“ 1-5
PL Series Single Phase Main Lug & Main Breaker Load Centers 1-6
PL Series Single Phase Special Load Centers 1-7
PL Series Three Phase Main Lug & Main Breaker Load Centers 1-8
PL Series Three Phase Unassembled Load Centers 1-9
ES Series Load Centers Features and Product Offering 1-10 €“ 1-11
ES Series Single Phase Main Lug & Main Breaker Load Centers 1-12
ES Series Single Phase Special Load Centers 1-14
ES Series Three Phase Main Lug & Main Breaker Load Centers 1-15




Let me guess, you voted for Trump?


Where did you see them call their products anything but single phase
or 3 phase?

On Tue, 24 Jul 2018 06:53:13 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 7:43:54 AM UTC-4, Bubba wrote:
On 7/24/2018 5:45 AM, trader_4 wrote:
How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.

Grab a dual-trace oscilloscope.

Connect the Scope Common lead to transformer L1

Connect Scope Trace 1 lead to the transformer center tap

Connect Scope Trace 2 lead to transformer L2


You'll observe two screen traces in perfect sync that vary only in amplitude.Â* Only a Hillary voter would mistake it for two-phase.

Did you read the link I posted to the discussion on that other forum?

https://forum.allaboutcircuits.com/t...-phase.105861/

The group moderator, Wbahn posted this:

Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?



Now run them to a house and tie them together so that you have 120VAC between the common and either of the other lines and 240VAC between the two lines. Would it still be reasonable to call this two-phase power?

Bubba?



Could you tell the difference between that situation and the one in which the wires coming to the house are from a center-tapped transformer?

Bubba?


If not, then wouldn't it be reasonable to use the same name for either?
(that was Wbahns final question)

Bubba?


And what he described would still show exactly the same thing on the scope
as the test you described. In all the above, if we changed the phase
difference to 90, would it then be two phase? How about to 179 deg?
In engineering we don't make it up case by case, we analyze the general
case. 180 is just one special case, where it's easy to generate two
voltage sources that are 180 deg out of phase with each other. Or go
take a look at the MIT electrical engineering course in power systems
where they show the mathematics of what
they call two phase power. There are simply two voltage sources
driving two loads. They do the analysis for a 90 deg phase difference,
but you could just as well do the same analysis for a difference of 70
degrees or 180 degrees. The same analysis, the same math applies,
because to the system, it is the same thing.

It's like Wbahn says, it's a matter of semantics and convention.

If you feel differently, then give us your definition of two phase,
3 phase, and N phase power and show us why split-phase is not also
two phases? The only way I see it's not would be to rule that special case
out by *definition*, which is back to the semantics. In that case,
if you can site the electrical body, authority, organization that
has done that, I'm sure we'd all like to see it.

From your discussion group
"So I would put forward the argument that the secondary is a center
tapped transformer providing 120v each side of the center(with center
hard wired to "earth"and providing the "neutral connection") and 220v
across the whole winding. This does NOT constitute a "2 phase" system"

Don't let electronIC engineers confuse the terminology used by
electricAL professionals. We use specific terminology to avoid
confusion and perhaps save lives. Homeowners and electronics geeks can
call things whatever they want but they only sound stupid when they
talk to the people who do this stuff for a living.

On Tue, 24 Jul 2018 11:28:29 -0400, Bubba
wrote:

On 7/24/2018 9:53 AM, trader_4 wrote:
Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?

The transformer for my house has a single phase input.Â* The output of the transformer is single phase as well.Â* I don't have a two-phase generator on my utility pole.


Trader thinks "SDS" is the predecessor of Antifa. ;-)

On Tue, 24 Jul 2018 08:57:29 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 11:28:39 AM UTC-4, Bubba wrote:
On 7/24/2018 9:53 AM, trader_4 wrote:
Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?

The transformer for my house has a single phase input.Â* The output of the transformer is single phase as well.Â* I don't have a two-phase generator on my utility pole.

There you have it, typical. Instead of responding to the simple questions
that go to the heart of the matter, just diversion. Others can note that
I responded to your oscilloscope connection question. Note that I also
gave you an opportunity to define for us what makes a system one phase,
two phase, N phase and then explain why residential doesn't meet the
definition of two phase. If you can't define it, then it becomes
arbitrary. Which is kind of what I and the moderator at the forum said,
it's just semantics.

When there is already something called "2 phase" applying that term to
a single phase circuit is silly.
I suppose you will want to call 3 p center tap delta "4 phase".

trader_4 posted for all of us...



On Monday, July 23, 2018 at 5:02:39 PM UTC-4, Walt's Electric wrote:
On 7/23/2018 7:04 AM, wrote:
If this were a 2 phase panel, such as almost all residential panels are, it would have 2 hot lines and one neutral. In this case if the loads are balanced the current in the neutral will be zero. With unbalanced loads the current in the neutral is the difference between the 2 hot lines. Because the current in one is 180 degrees out of phase with the other the current from one cancels out the current from the other. Best practice is to try to
keep the loads balanced as much as possible.

I've never seen a two-phase residential panel at lowes or home depot.* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


Oh no, here we go again.

Exactly...

--
Tekkie

On Tue, 24 Jul 2018 15:26:18 -0400, Tekkie®
wrote:

trader_4 posted for all of us...



On Monday, July 23, 2018 at 5:02:39 PM UTC-4, Walt's Electric wrote:
On 7/23/2018 7:04 AM, wrote:
If this were a 2 phase panel, such as almost all residential panels are, it would have 2 hot lines and one neutral. In this case if the loads are balanced the current in the neutral will be zero. With unbalanced loads the current in the neutral is the difference between the 2 hot lines. Because the current in one is 180
degrees out of phase with the other the current from one cancels out the current from the other. Best practice is to try to
keep the loads balanced as much as possible.

I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


Oh no, here we go again.

Exactly...

I guess we are ready for the old NEMA 5-15 ground pin orientation
argument again. ;-)

On 7/24/2018 9:54 AM, trader_4 wrote:
On Tuesday, July 24, 2018 at 8:55:23 AM UTC-4, Bubba wrote:
On 07/24/2018 07:47 AM, BurfordTJustice wrote:
LOL!! 3 pointer!!
Thanks Coach!

Yes, thanking the Russian troll who creates dozens off OT, divisive,
stupid threads a day is a good way to add to your credibility.
Birds of a feather....

Be that as it may ;-) , at least Burford understands the difference between single and two-phase...and he is typically on the "right" side of a political argument.

On 7/24/2018 11:57 AM, trader_4 wrote:
There you have it, typical. Instead of responding to the simple questions
that go to the heart of the matter, just diversion. Others can note that
I responded to your oscilloscope connection question. Note that I also
gave you an opportunity to define for us what makes a system one phase,
two phase, N phase and then explain why residential doesn't meet the
definition of two phase. If you can't define it, then it becomes
arbitrary. Which is kind of what I and the moderator at the forum said,
it's just semantics.

Sometimes the authorities/experts are wrong.Â* For example, your boy Slick Willy Clinton once claimed that a blow job was not sex...despite the fact that a blow job is more formally known as oral sex.

So was your boy lying or telling the truth?

On Tuesday, July 24, 2018 at 12:41:18 PM UTC-4, wrote:
On Tue, 24 Jul 2018 02:45:45 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 10:14:18 PM UTC-4, wrote:
On Mon, 23 Jul 2018 17:47:02 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 8:24:43 PM UTC-4, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you? I really didn't expect I'd be waking anyone up by responding to a 7 year old post.

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase..

I even found a presentation a power industry engineer made at
a conference where he made the case that to correctly analyze a split-phase
system you have to treat it like what it is, a system with two phases..

The other argument is that if I start with a 3 phase system going into
a building, everyone agrees that there are 3 phases there, right? You can see
them on an oscilloscope. Now let;s remove one. How many phases now?
Two. Now instead of the phases being 120 apart, let's move one so that
they are 180 apart. How many phases now? Two. And if you look at it on a
a scope, it looks exactly like a split-phase gsystem going into the
same building and it behaves exactly like it. Electrically you can't
distinguish one from the other, they are the same thing.

That's my case, others will probably draw different conclusions.

There is single phase, 2 phase (that I doubt anyone here has ever
seen) and 3 phase. If you only use 2 legs of a 3 phase circuit, it is
single phase.

You have to start with the electrical engineering
definition of phase. It's simply the relationship between two periodic
waveforms. That's how we got the term three phase power to begin with.
It's based on the fact that the power is being generated as three separate
waveforms which are separated by 120 degrees.

Here is a good discussion going back and forth:

https://forum.allaboutcircuits.com/t...-phase.105861/


I agree with Wbahn, the group moderator there, he's saying it's about semantics.
And note whenever anyone is challenged as to why it can't be called two phase,
it all falls back to arguments, like "but two phase was 90 deg phase difference
and it doesn't exist anymore". When challenged along the lines of how you
define phase, why if you change 90 to 180, which is just one of the many
possibilities, it suddenly can't be called two phases anymore, they have
no electrical engineering answer, no definition, it's just that they
say it isn't. Change the phase angle
from 90 to 95, would it still be two phases? Why when it reaches 180 is
it no longer two phases? When it's at 185, would it be two phases again?

The argument Wbahn makes about a single shaft generator, instead of
supplying 3 phase, make one that supplies 2 phases, at the 90
deg if you like. Two windings, differing by 90 deg, supplying two
hots with a common neutral. Would that be two phases? If not,
why not? And if yes, then why isn't it two phases if I change the
phase angle to 180? If you agree that there are two phases still
there, then that is indistinguishable from the split-phase service
that enters your house. It's all about semantics and you have to
start with the definition of phase. Phase is simply the relationship
between two periodic waveforms.



Here, from MIT, an introduction to power systems, where they start out
with the simple case of a power system with two phases.
Note it's only about two voltage sources connected to two
loads, with two voltage sources that can be at any phase angle.
Nothing about where the voltage source originated from or what the phase angle
is. Nothing about magic happening at 180 degrees, where it's no longer
a two phase system. It's the completely general electrical engineering
case of what defines a two phase power system and how you analyze it.

https://ocw.mit.edu/courses/electric...061S11_ch3.pdf

Make those two voltage sources be the two sides of the transformer on the
pole at your house and it;s the split-phase service that serves your house.







Where you ground that does not change the number of phases.
In fact 3 phase center tapped delta is just your regular single phase
center tapped transformer connected to a delta primary with another
transformer (or two) providing the 3d phase.
OTOH if you corner grounded that delta you would have 2 (hot)
ungrounded conductors and a neutral with 2 pole breakers but it is
clearly still 3 phase.
Two phase is a totally different breed of cat with 2 phases (4 wires)
90 degrees out of phase. This will usually be 2 transformers center
tapped with the center taps grounded (5 wire).
Split phase is a type of motor winding, perhaps the most common for AC
compressors and other applications that use a start capacitor and no
run capacitor. The "phase" is "split" by a start winding 90 degrees
out of phase with the run winding.

How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.


It is single phase. There is only one secondary winding derived from a
single phase primary. The fact that you center tap that winding and
ground that tap does not magically add a phase.

Yes it does, it creates two voltage sources that are 180 deg out of
phase with each other. Why didn't you address the example in that other
forum? I take two single winding generators, connect them on a single
shaft at the power station. One winding is 180 deg out of phase with
the other, they share a common neutral. Now you have two windings,
does that make it two phase?




I suppose the unknowing can call it anything they want but
professionals call your typical home service 120/240 single phase.

Do you ever read what I post? From my first post:

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

So, I really don't understand the problem here.

And then we heard from someone who at least thinks he's a *professional*,
Ed's Electric, saying:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."


I provided links to Siemens, Square D, etc. where they call their panels used
for split-phase service "single phase". Funny I didn't see you correcting
that guy, but here you are all over me, when I agreed that I would CALL IT
split-phase service, because that most accurately describes what it is.
I've said I would not call it two
phase service, because that is not the convention. But that doesn't change
how you ANALYZE it or what's there. This is like arguing that you have
to only describe what we commonly call tissues as Kleenex. Or maybe as
"tissues", that you can't describe them as a very soft, thin paper product
that;s made from trees and used to blow your nose. I'm sure there are
industry specs, details that more accurately describe tissues too, if
you look into it. So, we can't say that tissues are really that, you
can only say Kleenex because that's what the most common used term is?
It's exactly what the poster in that other forum said, it's a question
of semantics.



If I used your logic, a string of Christmas tree lights is "100 split
phases" because I would see a separate little 1.2v wave form across
each of the 100 bulbs on a scope and each one would be 180 degrees out
of phase from the bulb on the other side of the common lead on the
scope.

If you define what the voltages you're looking at in that circuit,
the polarity, V1 across bulb one, V2 across bulb two, V3 across
four bulbs, etc, you could attach a scope and show the various
waveforms. Some would be 1.2V, some would be 4.8V, some would
have one polarity, some would have the other depending on how
you defines the polarity of the measurement points and you could display
them on a scope. You could do it for a class in electrical basics.
Then ask the class to analyze the relationships of those waveforms on
a test. If a student was asked about your two bulb example, to
explain what he sees in the picture from the scope and he answered:

Both are 60 hz sinusoidal waveforms, both are 1.2V, one is 180 degrees
out of phase with the other, is he wrong? Is that an incorrect answer?


And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

On Tuesday, July 24, 2018 at 12:41:47 PM UTC-4, wrote:
On Tue, 24 Jul 2018 06:29:01 -0400, Ed's Electric
wrote:

On 07/23/2018 08:24 PM, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?

OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you?

No, professionals call it single-phase.Â* Unless you want people to think you voted for Hillary, you should use the proper terminology.




;-)

I guess you didn't look at the links I provided where Siemens, Square D and
other manufacturers of panels call their split-phase panels "single phase".
I guess there are no professionals there.....

On Tuesday, July 24, 2018 at 12:44:44 PM UTC-4, wrote:
On Tue, 24 Jul 2018 04:05:27 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 6:29:06 AM UTC-4, Ed's Electric wrote:
On 07/23/2018 08:24 PM, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?

OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you?

No, professionals call it single-phase.Â* Unless you want people to think you voted for Hillary, you should use the proper terminology.



Guess this manufacturer of panels, a former GE subsidiary, isn't professional?


http://www.geindustrial.com/products...ngle-phase-usa


PowerMark Gold* Single Phase - USA

PowerMark Gold - Single Phase - US

Homesphere

This product qualifies for HomeSphere** builder incentives.



PowerMark Gold load centers lower your costs by making installation faster and easier, increasing application flexibility and reducing inventory requirements. At the same time, they deliver obvious and significant advances in design, function and quality.
Features and Benefits

40-225 Amps main breaker
2 - 42 feeder circuits
22kAIC main breaker, series rated 22/10
Sturdy copper bus and galvanized box increase durability and reliability
Reduces total cost through faster, easier installation; enhanced application flexibility; and reduced inventory requirements
Solid neutrals for quick, easy, secure terminations
Available with white front



Or Square D:

Are I-Line panels available as single phase?
Issue:
Does Square D offer I-line panelboards in 1-phase?

Product Line:
Distribution panelboards

Environment:
I-line panelboards

Cause:
Product features.

Resolution:
Yes. Order a standard I-Line panel and only order breakers that are phased A-C.


Or Siemens?


https://w3.usa.siemens.com/powerdist...01-ALL-web.pdf

C o n t e n t s
Load Centers
Catalog Numbering System 1-2
Siemens PL and ES Series Load Centers„¢ Introduction 1-3
WireGuide„¢ Load Centers and Breakers 1-3
PL Series Load Centers Features and Product Offering 1-4 €“ 1-5
PL Series Single Phase Main Lug & Main Breaker Load Centers 1-6
PL Series Single Phase Special Load Centers 1-7
PL Series Three Phase Main Lug & Main Breaker Load Centers 1-8
PL Series Three Phase Unassembled Load Centers 1-9
ES Series Load Centers Features and Product Offering 1-10 €“ 1-11
ES Series Single Phase Main Lug & Main Breaker Load Centers 1-12
ES Series Single Phase Special Load Centers 1-14
ES Series Three Phase Main Lug & Main Breaker Load Centers 1-15




Let me guess, you voted for Trump?


Where did you see them call their products anything but single phase
or 3 phase?


Do you ever read what I post before going at it?

"We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase."

On Tuesday, July 24, 2018 at 12:53:33 PM UTC-4, wrote:
On Tue, 24 Jul 2018 06:53:13 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 7:43:54 AM UTC-4, Bubba wrote:
On 7/24/2018 5:45 AM, trader_4 wrote:
How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.

Grab a dual-trace oscilloscope.

Connect the Scope Common lead to transformer L1

Connect Scope Trace 1 lead to the transformer center tap

Connect Scope Trace 2 lead to transformer L2


You'll observe two screen traces in perfect sync that vary only in amplitude.Â* Only a Hillary voter would mistake it for two-phase.

Did you read the link I posted to the discussion on that other forum?

https://forum.allaboutcircuits.com/t...-phase.105861/

The group moderator, Wbahn posted this:

Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?



Now run them to a house and tie them together so that you have 120VAC between the common and either of the other lines and 240VAC between the two lines. Would it still be reasonable to call this two-phase power?

Bubba?



Could you tell the difference between that situation and the one in which the wires coming to the house are from a center-tapped transformer?

Bubba?


If not, then wouldn't it be reasonable to use the same name for either?
(that was Wbahns final question)

Bubba?


And what he described would still show exactly the same thing on the scope
as the test you described. In all the above, if we changed the phase
difference to 90, would it then be two phase? How about to 179 deg?
In engineering we don't make it up case by case, we analyze the general
case. 180 is just one special case, where it's easy to generate two
voltage sources that are 180 deg out of phase with each other. Or go
take a look at the MIT electrical engineering course in power systems
where they show the mathematics of what
they call two phase power. There are simply two voltage sources
driving two loads. They do the analysis for a 90 deg phase difference,
but you could just as well do the same analysis for a difference of 70
degrees or 180 degrees. The same analysis, the same math applies,
because to the system, it is the same thing.

It's like Wbahn says, it's a matter of semantics and convention.

If you feel differently, then give us your definition of two phase,
3 phase, and N phase power and show us why split-phase is not also
two phases? The only way I see it's not would be to rule that special case
out by *definition*, which is back to the semantics. In that case,
if you can site the electrical body, authority, organization that
has done that, I'm sure we'd all like to see it.

From your discussion group
"So I would put forward the argument that the secondary is a center
tapped transformer providing 120v each side of the center(with center
hard wired to "earth"and providing the "neutral connection") and 220v
across the whole winding. This does NOT constitute a "2 phase" system"

I didn't say there were not others there arguing the other side.
Funny thing though, none of these "professionals" are able to define
what single phase, two phase, three phase, N phase power means.





Don't let electronIC engineers confuse the terminology used by
electricAL professionals. We use specific terminology to avoid
confusion and perhaps save lives. Homeowners and electronics geeks can
call things whatever they want but they only sound stupid when they
talk to the people who do this stuff for a living.



Are you sure you want to now resort to disparaging electronic engineers
as not professional and stupid? Funny I didn't see you ripping into
this alleged "professional", Ed's Electric that posted:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."

You gave him a wink. I guess that was before you saw the links I provided
to Siemens, Square D, that show they call their panels single phase.
That;s what they call them in the product catalog, in the index, etc.
Doh!

On Tuesday, July 24, 2018 at 1:45:53 PM UTC-4, wrote:
On Tue, 24 Jul 2018 08:57:29 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 11:28:39 AM UTC-4, Bubba wrote:
On 7/24/2018 9:53 AM, trader_4 wrote:
Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?

The transformer for my house has a single phase input.Â* The output of the transformer is single phase as well.Â* I don't have a two-phase generator on my utility pole.

There you have it, typical. Instead of responding to the simple questions
that go to the heart of the matter, just diversion. Others can note that
I responded to your oscilloscope connection question. Note that I also
gave you an opportunity to define for us what makes a system one phase,
two phase, N phase and then explain why residential doesn't meet the
definition of two phase. If you can't define it, then it becomes
arbitrary. Which is kind of what I and the moderator at the forum said,
it's just semantics.

When there is already something called "2 phase" applying that term to
a single phase circuit is silly.
I suppose you will want to call 3 p center tap delta "4 phase".

Do you ever read what I actually post? From my first post on the matter
he


We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

Or respond to a direct question that goes to the core of the issue:

Give us your electrical engineering definition of one phase, two phase,
three phase and N phase power and then explain why split phase doesn't
meet the definition of two phase.

On Tuesday, July 24, 2018 at 6:09:19 PM UTC-4, Bubba wrote:
On 7/24/2018 9:54 AM, trader_4 wrote:
On Tuesday, July 24, 2018 at 8:55:23 AM UTC-4, Bubba wrote:
On 07/24/2018 07:47 AM, BurfordTJustice wrote:
LOL!! 3 pointer!!
Thanks Coach!

Yes, thanking the Russian troll who creates dozens off OT, divisive,
stupid threads a day is a good way to add to your credibility.
Birds of a feather....

Be that as it may ;-) , at least Burford understands the difference between single and two-phase...and he is typically on the "right" side of a political argument.

Then maybe BurpFart can give us the definitions of one phase, two phase,
three phase, N phase power and explain why split-phase into a house
doesn't meet the definition of two phase. So far, none of the others
here can.

On 07/24/2018 12:45 PM, wrote:

[snip]

I suppose you will want to call 3 p center tap delta "4 phase".

Isn't the center tap neutral, not a phase?

On 07/25/2018 10:14 AM, trader_4 wrote:

[snip]

And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

Whether you get 1 phase (and 2 different voltages) or 2 phases from a
center-tapped transformer depends on what point you use for a reference.
Using one end gives you 1 phase, using the center tap gives you 2.
Normally, it's the center tap that's grounded.

On Wed, 25 Jul 2018 08:14:37 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:41:18 PM UTC-4, wrote:
On Tue, 24 Jul 2018 02:45:45 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 10:14:18 PM UTC-4, wrote:
On Mon, 23 Jul 2018 17:47:02 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 8:24:43 PM UTC-4, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you? I really didn't expect I'd be waking anyone up by responding to a 7 year old post.

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

I even found a presentation a power industry engineer made at
a conference where he made the case that to correctly analyze a split-phase
system you have to treat it like what it is, a system with two phases.

The other argument is that if I start with a 3 phase system going into
a building, everyone agrees that there are 3 phases there, right? You can see
them on an oscilloscope. Now let;s remove one. How many phases now?
Two. Now instead of the phases being 120 apart, let's move one so that
they are 180 apart. How many phases now? Two. And if you look at it on a
a scope, it looks exactly like a split-phase gsystem going into the
same building and it behaves exactly like it. Electrically you can't
distinguish one from the other, they are the same thing.

That's my case, others will probably draw different conclusions.

There is single phase, 2 phase (that I doubt anyone here has ever
seen) and 3 phase. If you only use 2 legs of a 3 phase circuit, it is
single phase.

You have to start with the electrical engineering
definition of phase. It's simply the relationship between two periodic
waveforms. That's how we got the term three phase power to begin with.
It's based on the fact that the power is being generated as three separate
waveforms which are separated by 120 degrees.

Here is a good discussion going back and forth:

https://forum.allaboutcircuits.com/t...-phase.105861/


I agree with Wbahn, the group moderator there, he's saying it's about semantics.
And note whenever anyone is challenged as to why it can't be called two phase,
it all falls back to arguments, like "but two phase was 90 deg phase difference
and it doesn't exist anymore". When challenged along the lines of how you
define phase, why if you change 90 to 180, which is just one of the many
possibilities, it suddenly can't be called two phases anymore, they have
no electrical engineering answer, no definition, it's just that they
say it isn't. Change the phase angle
from 90 to 95, would it still be two phases? Why when it reaches 180 is
it no longer two phases? When it's at 185, would it be two phases again?

The argument Wbahn makes about a single shaft generator, instead of
supplying 3 phase, make one that supplies 2 phases, at the 90
deg if you like. Two windings, differing by 90 deg, supplying two
hots with a common neutral. Would that be two phases? If not,
why not? And if yes, then why isn't it two phases if I change the
phase angle to 180? If you agree that there are two phases still
there, then that is indistinguishable from the split-phase service
that enters your house. It's all about semantics and you have to
start with the definition of phase. Phase is simply the relationship
between two periodic waveforms.



Here, from MIT, an introduction to power systems, where they start out
with the simple case of a power system with two phases.
Note it's only about two voltage sources connected to two
loads, with two voltage sources that can be at any phase angle.
Nothing about where the voltage source originated from or what the phase angle
is. Nothing about magic happening at 180 degrees, where it's no longer
a two phase system. It's the completely general electrical engineering
case of what defines a two phase power system and how you analyze it.

https://ocw.mit.edu/courses/electric...061S11_ch3.pdf

Make those two voltage sources be the two sides of the transformer on the
pole at your house and it;s the split-phase service that serves your house.







Where you ground that does not change the number of phases.
In fact 3 phase center tapped delta is just your regular single phase
center tapped transformer connected to a delta primary with another
transformer (or two) providing the 3d phase.
OTOH if you corner grounded that delta you would have 2 (hot)
ungrounded conductors and a neutral with 2 pole breakers but it is
clearly still 3 phase.
Two phase is a totally different breed of cat with 2 phases (4 wires)
90 degrees out of phase. This will usually be 2 transformers center
tapped with the center taps grounded (5 wire).
Split phase is a type of motor winding, perhaps the most common for AC
compressors and other applications that use a start capacitor and no
run capacitor. The "phase" is "split" by a start winding 90 degrees
out of phase with the run winding.

How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.


It is single phase. There is only one secondary winding derived from a
single phase primary. The fact that you center tap that winding and
ground that tap does not magically add a phase.

Yes it does, it creates two voltage sources that are 180 deg out of
phase with each other. Why didn't you address the example in that other
forum? I take two single winding generators, connect them on a single
shaft at the power station. One winding is 180 deg out of phase with
the other, they share a common neutral. Now you have two windings,
does that make it two phase?




I suppose the unknowing can call it anything they want but
professionals call your typical home service 120/240 single phase.

Do you ever read what I post? From my first post:

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

So, I really don't understand the problem here.

And then we heard from someone who at least thinks he's a *professional*,
Ed's Electric, saying:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."


I provided links to Siemens, Square D, etc. where they call their panels used
for split-phase service "single phase". Funny I didn't see you correcting
that guy, but here you are all over me, when I agreed that I would CALL IT
split-phase service, because that most accurately describes what it is.
I've said I would not call it two
phase service, because that is not the convention. But that doesn't change
how you ANALYZE it or what's there. This is like arguing that you have
to only describe what we commonly call tissues as Kleenex. Or maybe as
"tissues", that you can't describe them as a very soft, thin paper product
that;s made from trees and used to blow your nose. I'm sure there are
industry specs, details that more accurately describe tissues too, if
you look into it. So, we can't say that tissues are really that, you
can only say Kleenex because that's what the most common used term is?
It's exactly what the poster in that other forum said, it's a question
of semantics.



If I used your logic, a string of Christmas tree lights is "100 split
phases" because I would see a separate little 1.2v wave form across
each of the 100 bulbs on a scope and each one would be 180 degrees out
of phase from the bulb on the other side of the common lead on the
scope.

If you define what the voltages you're looking at in that circuit,
the polarity, V1 across bulb one, V2 across bulb two, V3 across
four bulbs, etc, you could attach a scope and show the various
waveforms. Some would be 1.2V, some would be 4.8V, some would
have one polarity, some would have the other depending on how
you defines the polarity of the measurement points and you could display
them on a scope. You could do it for a class in electrical basics.
Then ask the class to analyze the relationships of those waveforms on
a test. If a student was asked about your two bulb example, to
explain what he sees in the picture from the scope and he answered:

Both are 60 hz sinusoidal waveforms, both are 1.2V, one is 180 degrees
out of phase with the other, is he wrong? Is that an incorrect answer?


And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't. They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.
I really don't care anymore. You can sound stupid if you want, your
choice but 120/240 is single phase to the people who do this for a
living. It is only homeowners and hacks who call it anything else.

On Wed, 25 Jul 2018 08:16:29 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:41:47 PM UTC-4, wrote:
On Tue, 24 Jul 2018 06:29:01 -0400, Ed's Electric
wrote:

On 07/23/2018 08:24 PM, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?

OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you?

No, professionals call it single-phase.Â* Unless you want people to think you voted for Hillary, you should use the proper terminology.




;-)

I guess you didn't look at the links I provided where Siemens, Square D and
other manufacturers of panels call their split-phase panels "single phase".
I guess there are no professionals there.....

I didn't see them say "split" anything. They just said what we have
been saying. A 120/240v panel is single phase.

On Wed, 25 Jul 2018 08:32:41 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:44:44 PM UTC-4, wrote:
On Tue, 24 Jul 2018 04:05:27 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 6:29:06 AM UTC-4, Ed's Electric wrote:
On 07/23/2018 08:24 PM, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?

OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you?

No, professionals call it single-phase.Â* Unless you want people to think you voted for Hillary, you should use the proper terminology.



Guess this manufacturer of panels, a former GE subsidiary, isn't professional?


http://www.geindustrial.com/products...ngle-phase-usa


PowerMark Gold* Single Phase - USA

PowerMark Gold - Single Phase - US

Homesphere

This product qualifies for HomeSphere** builder incentives.



PowerMark Gold load centers lower your costs by making installation faster and easier, increasing application flexibility and reducing inventory requirements. At the same time, they deliver obvious and significant advances in design, function and quality.
Features and Benefits

40-225 Amps main breaker
2 - 42 feeder circuits
22kAIC main breaker, series rated 22/10
Sturdy copper bus and galvanized box increase durability and reliability
Reduces total cost through faster, easier installation; enhanced application flexibility; and reduced inventory requirements
Solid neutrals for quick, easy, secure terminations
Available with white front



Or Square D:

Are I-Line panels available as single phase?
Issue:
Does Square D offer I-line panelboards in 1-phase?

Product Line:
Distribution panelboards

Environment:
I-line panelboards

Cause:
Product features.

Resolution:
Yes. Order a standard I-Line panel and only order breakers that are phased A-C.


Or Siemens?


https://w3.usa.siemens.com/powerdist...01-ALL-web.pdf

C o n t e n t s
Load Centers
Catalog Numbering System 1-2
Siemens PL and ES Series Load Centers„¢ Introduction 1-3
WireGuide„¢ Load Centers and Breakers 1-3
PL Series Load Centers Features and Product Offering 1-4 €“ 1-5
PL Series Single Phase Main Lug & Main Breaker Load Centers 1-6
PL Series Single Phase Special Load Centers 1-7
PL Series Three Phase Main Lug & Main Breaker Load Centers 1-8
PL Series Three Phase Unassembled Load Centers 1-9
ES Series Load Centers Features and Product Offering 1-10 €“ 1-11
ES Series Single Phase Main Lug & Main Breaker Load Centers 1-12
ES Series Single Phase Special Load Centers 1-14
ES Series Three Phase Main Lug & Main Breaker Load Centers 1-15




Let me guess, you voted for Trump?


Where did you see them call their products anything but single phase
or 3 phase?


Do you ever read what I post before going at it?

"We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase."

Maybe some people call the "hots" phases but not people who know what
they are talking about (and that might even include some 1& 2 family
"electricians") Those are "ungrounded conductors".

The term "split phase" already exists, it refers to a type of motor
winding.
The term "2 phase" also exists. It refers to a system with 2 separate
phases, 90 degrees from each other using 4 ungrounded conductors and a
center tapped neutral.
The fact that you center tap a phase does not create more phases, it
just establishes where the ground reference is.
Like I asked, would you call 3 phase delta with a center tapped
winding "4 phase".
Is corner grounded delta suddenly single phase (or "split/2 phase") It
would certainly look like it to the average untrained person. There
are 2 ungrounded conductors and a white neutral with a 2 pole service
disconnect.

On Wed, 25 Jul 2018 08:39:37 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:53:33 PM UTC-4, wrote:
On Tue, 24 Jul 2018 06:53:13 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 7:43:54 AM UTC-4, Bubba wrote:
On 7/24/2018 5:45 AM, trader_4 wrote:
How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.

Grab a dual-trace oscilloscope.

Connect the Scope Common lead to transformer L1

Connect Scope Trace 1 lead to the transformer center tap

Connect Scope Trace 2 lead to transformer L2


You'll observe two screen traces in perfect sync that vary only in amplitude.Â* Only a Hillary voter would mistake it for two-phase.

Did you read the link I posted to the discussion on that other forum?

https://forum.allaboutcircuits.com/t...-phase.105861/

The group moderator, Wbahn posted this:

Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?



Now run them to a house and tie them together so that you have 120VAC between the common and either of the other lines and 240VAC between the two lines. Would it still be reasonable to call this two-phase power?

Bubba?



Could you tell the difference between that situation and the one in which the wires coming to the house are from a center-tapped transformer?

Bubba?


If not, then wouldn't it be reasonable to use the same name for either?
(that was Wbahns final question)

Bubba?


And what he described would still show exactly the same thing on the scope
as the test you described. In all the above, if we changed the phase
difference to 90, would it then be two phase? How about to 179 deg?
In engineering we don't make it up case by case, we analyze the general
case. 180 is just one special case, where it's easy to generate two
voltage sources that are 180 deg out of phase with each other. Or go
take a look at the MIT electrical engineering course in power systems
where they show the mathematics of what
they call two phase power. There are simply two voltage sources
driving two loads. They do the analysis for a 90 deg phase difference,
but you could just as well do the same analysis for a difference of 70
degrees or 180 degrees. The same analysis, the same math applies,
because to the system, it is the same thing.

It's like Wbahn says, it's a matter of semantics and convention.

If you feel differently, then give us your definition of two phase,
3 phase, and N phase power and show us why split-phase is not also
two phases? The only way I see it's not would be to rule that special case
out by *definition*, which is back to the semantics. In that case,
if you can site the electrical body, authority, organization that
has done that, I'm sure we'd all like to see it.

From your discussion group
"So I would put forward the argument that the secondary is a center
tapped transformer providing 120v each side of the center(with center
hard wired to "earth"and providing the "neutral connection") and 220v
across the whole winding. This does NOT constitute a "2 phase" system"

I didn't say there were not others there arguing the other side.
Funny thing though, none of these "professionals" are able to define
what single phase, two phase, three phase, N phase power means.





Don't let electronIC engineers confuse the terminology used by
electricAL professionals. We use specific terminology to avoid
confusion and perhaps save lives. Homeowners and electronics geeks can
call things whatever they want but they only sound stupid when they
talk to the people who do this stuff for a living.



Are you sure you want to now resort to disparaging electronic engineers
as not professional and stupid? Funny I didn't see you ripping into
this alleged "professional", Ed's Electric that posted:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."

You gave him a wink. I guess that was before you saw the links I provided
to Siemens, Square D, that show they call their panels single phase.
That;s what they call them in the product catalog, in the index, etc.
Doh!



Your reference to the panel descriptions confirm what we say.
There are no "split phase" panels, nor are they calling any of them "2
phase". They sell single phase panels and 3 phase panels.

As for electronic engineers, they simply use different terminology.
They look at things from a different perspective. You will also find
the voltage drop charts they use are different too. It doesn't mean
they use different copper or wire sizes. They just apply different
conditions when they rate the wire. Electronics people generally make
lousy electricians. I have lived in both worlds and there is a vast
cultural divide between them,.

I have defined single phase to you several times but let's try it
again. It is a system derived from a single secondary winding of a
transformer. (or a single rotating field in a generator/alternator
stator). The fact that you ground the center tap of that secondary
does not change a thing as far as the number of phases in concerned.
There is still one sine wave generated (a single phase) and that does
not change no matter where you stand to look at it.

3 phase is derived from 3 separate secondary windings (although you
can delete one and it still works) with three distinct sine waves, 120
degrees out of phase with each other. It is necessary to start with a
3 phase primary too. That can be grounded at the center tap of one
transformer in a delta configuration, at the end tap of two adjacent
transformers of a delta configuration or at the end tap of all three
in a wye configuration.
You can even leave that ungrounded, typically as a delta.
It is still always going to be 3 phase.
Anything derived from a single secondary winding will be single phase,
center tapped or not.

2 phase is derived from 2 windings, 90 degrees out of phase with each
other.
Your 2 generators is a red herring but if you must, when you tie them
together, they are in phase with each other and that is still a single
phase. In fact when you do tie generators together, they will sync up,
if they don't burn each other out before they do. The grid does that
every day.

On Wed, 25 Jul 2018 11:36:10 -0500, notX
wrote:

On 07/24/2018 12:45 PM, wrote:

[snip]

I suppose you will want to call 3 p center tap delta "4 phase".

Isn't the center tap neutral, not a phase?


A phase refers to the angular displacement of the sine wave. Center
tapping a winding does not change the angular displacement. it is
still one sine wave, you are just looking at it from the middle.

Think about walking up a ramp. It is just one ramp with one slope but
when you are in the middle, one way is up and the other way is down.
The ramp did not change, only the place where you are standing.

On 7/25/2018 1:25 PM, wrote:
I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't. They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.
I really don't care anymore. You can sound stupid if you want, your
choice but 120/240 is single phase to the people who do this for a
living. It is only homeowners and hacks who call it anything else.

If a the transformer secondary had 2 equally spaced taps, would LymeBoi call it 3-phase?

On Wednesday, July 25, 2018 at 12:45:09 PM UTC-4, Sam E wrote:
On 07/25/2018 10:14 AM, trader_4 wrote:

[snip]

And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

Whether you get 1 phase (and 2 different voltages) or 2 phases from a
center-tapped transformer depends on what point you use for a reference.
Using one end gives you 1 phase, using the center tap gives you 2.
Normally, it's the center tap that's grounded.

I agree, that's a good point, but it is being used center tapped neutral
for what we're discussing.

On Wed, 25 Jul 2018 16:42:00 -0700 (PDT), trader_4
wrote:

On Wednesday, July 25, 2018 at 12:45:09 PM UTC-4, Sam E wrote:
On 07/25/2018 10:14 AM, trader_4 wrote:

[snip]

And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

Whether you get 1 phase (and 2 different voltages) or 2 phases from a
center-tapped transformer depends on what point you use for a reference.
Using one end gives you 1 phase, using the center tap gives you 2.
Normally, it's the center tap that's grounded.

I agree, that's a good point, but it is being used center tapped neutral
for what we're discussing.



Simply because you look at a single phase from a different spot does
not make it 2 phases.
If I give you a sandwich and cut it in half you don't have 2
sandwiches.

On Wednesday, July 25, 2018 at 2:04:26 PM UTC-4, wrote:
On Wed, 25 Jul 2018 08:39:37 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:53:33 PM UTC-4, wrote:
On Tue, 24 Jul 2018 06:53:13 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 7:43:54 AM UTC-4, Bubba wrote:
On 7/24/2018 5:45 AM, trader_4 wrote:
How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.

Grab a dual-trace oscilloscope.

Connect the Scope Common lead to transformer L1

Connect Scope Trace 1 lead to the transformer center tap

Connect Scope Trace 2 lead to transformer L2


You'll observe two screen traces in perfect sync that vary only in amplitude.Â* Only a Hillary voter would mistake it for two-phase.

Did you read the link I posted to the discussion on that other forum?

https://forum.allaboutcircuits.com/t...-phase.105861/

The group moderator, Wbahn posted this:

Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?



Now run them to a house and tie them together so that you have 120VAC between the common and either of the other lines and 240VAC between the two lines. Would it still be reasonable to call this two-phase power?

Bubba?



Could you tell the difference between that situation and the one in which the wires coming to the house are from a center-tapped transformer?

Bubba?


If not, then wouldn't it be reasonable to use the same name for either?
(that was Wbahns final question)

Bubba?


And what he described would still show exactly the same thing on the scope
as the test you described. In all the above, if we changed the phase
difference to 90, would it then be two phase? How about to 179 deg?
In engineering we don't make it up case by case, we analyze the general
case. 180 is just one special case, where it's easy to generate two
voltage sources that are 180 deg out of phase with each other. Or go
take a look at the MIT electrical engineering course in power systems
where they show the mathematics of what
they call two phase power. There are simply two voltage sources
driving two loads. They do the analysis for a 90 deg phase difference,
but you could just as well do the same analysis for a difference of 70
degrees or 180 degrees. The same analysis, the same math applies,
because to the system, it is the same thing.

It's like Wbahn says, it's a matter of semantics and convention.

If you feel differently, then give us your definition of two phase,
3 phase, and N phase power and show us why split-phase is not also
two phases? The only way I see it's not would be to rule that special case
out by *definition*, which is back to the semantics. In that case,
if you can site the electrical body, authority, organization that
has done that, I'm sure we'd all like to see it.

From your discussion group
"So I would put forward the argument that the secondary is a center
tapped transformer providing 120v each side of the center(with center
hard wired to "earth"and providing the "neutral connection") and 220v
across the whole winding. This does NOT constitute a "2 phase" system"

I didn't say there were not others there arguing the other side.
Funny thing though, none of these "professionals" are able to define
what single phase, two phase, three phase, N phase power means.





Don't let electronIC engineers confuse the terminology used by
electricAL professionals. We use specific terminology to avoid
confusion and perhaps save lives. Homeowners and electronics geeks can
call things whatever they want but they only sound stupid when they
talk to the people who do this stuff for a living.



Are you sure you want to now resort to disparaging electronic engineers
as not professional and stupid? Funny I didn't see you ripping into
this alleged "professional", Ed's Electric that posted:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."

You gave him a wink. I guess that was before you saw the links I provided
to Siemens, Square D, that show they call their panels single phase.
That;s what they call them in the product catalog, in the index, etc.
Doh!



Your reference to the panel descriptions confirm what we say.
There are no "split phase" panels, nor are they calling any of them "2
phase". They sell single phase panels and 3 phase panels.

Who;s the "we". Ed's Electric posted that no professional would
ever call it single phase. And you appeared to agree with him,
you gave him a wink.

Again, in my very first post, I said I would
not call them two phase either. But what they are called and what is
there, what you see, how you analyze it are not one and the same.

Here, I found the presentation I referred to. It was made by a power
system engineeing professor with a career going back to the 60's.
He consults on power system, the presentation was made at a power engineering
conference and it's published by the IEEE. He last worked for Milsoft
Utility Solutions, that does work for power utilities. He doesn't
sound like a stupid guy or a homeowner.

https://ieeexplore.ieee.org/document/4520128/

Abstract:
Distribution engineers have treated the standard "singlephase" distribution transformer connection as single phase because from the primary side of the transformer these connections are single phase and in the case of standard rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Which now brings into focus the reality that standard 120/240 secondary systems are not single phase line to ground systems, instead they are three wire systems with two phases and one ground wires. Further, the standard 120/240 secondary is different from the two phase primary system in that the secondary phases are separated by 180 degrees instead of three phases separated by 120 degrees. What all of this means is that analysis software and methods must now deal with an electrical system requiring a different set of algorithms than those used to model and analyze the primary system. This paper will describe the modeling and analysis of the single-phase center tap transformer serving 120 Volt and 240 Volt single-phase loads from a three-wire secondary.

W. H. Kersting
Milsoft Utility Solutions, USA
W. H. Kersting (SM'64, F'89, Life Fellow 2003) was born in Santa Fe, NM. He received the BSEE degree from New Mexico State University, Las Cruces, and the MSEE degree from Illinois Institute of Technology. He joined the faculty at New Mexico State University in 1962 and served as Professor of Electrical Engineering and Director of the Electric Utility Management Program until his retirement in 2002. He is currently a consultant for Milsoft Utility Solutions. He is also a partner in WH Power Consultants, Las Cruces, NM.


And he's saying pretty much what I'm saying, that yes it's derived
from a single phase, center tapped transformer, but to correctly
analyze it, model it, you treat it as having two phases. Note, he
didn't say to call it two phase power, neither did I.




As for electronic engineers, they simply use different terminology.
They look at things from a different perspective. You will also find
the voltage drop charts they use are different too. It doesn't mean
they use different copper or wire sizes. They just apply different
conditions when they rate the wire. Electronics people generally make
lousy electricians. I have lived in both worlds and there is a vast
cultural divide between them,.

I have defined single phase to you several times but let's try it
again. It is a system derived from a single secondary winding of a
transformer. (or a single rotating field in a generator/alternator
stator).

So, if I create the generator example where I use two windings in
the generator 180 out of phase on a single shaft, share a common
neutral, that's not single phase because it has two secondary windings?
I don't see the number of windings being the issue.


The fact that you ground the center tap of that secondary
does not change a thing as far as the number of phases in concerned.
There is still one sine wave generated (a single phase) and that does
not change no matter where you stand to look at it.

I agree that there is only one sine wave generated. What I don't get
and what you haven't explained is why if coming out of the generator
you had two hots 90 deg out of phase, that's two phase. I asked, but
never got answered from anyone here, supposed it's 170 deg instead?
Is that still two phase? If it's 190 deg is it two phase? Why if
it's 180 is it suddenly not? That's the problem. Science and engineering
likes rules, laws, explanations that fit the general case. And 180
would just seem to me to be one case of all the possible two phase
possibilities. And how exactly you generate it doesn't matter to
the box it's entering or how you analyze it. You can see that in
the MIT example two, they just used two ideal voltage sources, that
in their case were 90 degrees out. But you could use the same model,
same math to *analyze* 120 deg, or (oh no), 180 couldn't you?



I agree after looking more at those panel makers, that they do use the term single phase, but other power system component manufacturers also call it split-phase, including other divisions of the same power system component
manufacturer, eg Siemens




3 phase is derived from 3 separate secondary windings (although you
can delete one and it still works) with three distinct sine waves, 120
degrees out of phase with each other. It is necessary to start with a
3 phase primary too. That can be grounded at the center tap of one
transformer in a delta configuration, at the end tap of two adjacent
transformers of a delta configuration or at the end tap of all three
in a wye configuration.
You can even leave that ungrounded, typically as a delta.
It is still always going to be 3 phase.
Anything derived from a single secondary winding will be single phase,
center tapped or not.

2 phase is derived from 2 windings, 90 degrees out of phase with each
other.

But again, that's not what we're talking about. That is the historical
case of what it once was. I think you will admit they didn't have to
make it 90, suppose it was 100 or 70? Would that still be two phase?
So, what's so special, so different that 180 suddenly can't be analyzed,
looked at as consisting of two phases? Yes it's a trivial case, but if
179 or 181 can be called two phase, then why not 180?

On Wednesday, July 25, 2018 at 1:25:32 PM UTC-4, wrote:
On Wed, 25 Jul 2018 08:14:37 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:41:18 PM UTC-4, wrote:
On Tue, 24 Jul 2018 02:45:45 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 10:14:18 PM UTC-4, wrote:
On Mon, 23 Jul 2018 17:47:02 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 8:24:43 PM UTC-4, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you? I really didn't expect I'd be waking anyone up by responding to a 7 year old post.

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

I even found a presentation a power industry engineer made at
a conference where he made the case that to correctly analyze a split-phase
system you have to treat it like what it is, a system with two phases.

The other argument is that if I start with a 3 phase system going into
a building, everyone agrees that there are 3 phases there, right? You can see
them on an oscilloscope. Now let;s remove one. How many phases now?
Two. Now instead of the phases being 120 apart, let's move one so that
they are 180 apart. How many phases now? Two. And if you look at it on a
a scope, it looks exactly like a split-phase gsystem going into the
same building and it behaves exactly like it. Electrically you can't
distinguish one from the other, they are the same thing.

That's my case, others will probably draw different conclusions.

There is single phase, 2 phase (that I doubt anyone here has ever
seen) and 3 phase. If you only use 2 legs of a 3 phase circuit, it is
single phase.

You have to start with the electrical engineering
definition of phase. It's simply the relationship between two periodic
waveforms. That's how we got the term three phase power to begin with.
It's based on the fact that the power is being generated as three separate
waveforms which are separated by 120 degrees.

Here is a good discussion going back and forth:

https://forum.allaboutcircuits.com/t...-phase.105861/


I agree with Wbahn, the group moderator there, he's saying it's about semantics.
And note whenever anyone is challenged as to why it can't be called two phase,
it all falls back to arguments, like "but two phase was 90 deg phase difference
and it doesn't exist anymore". When challenged along the lines of how you
define phase, why if you change 90 to 180, which is just one of the many
possibilities, it suddenly can't be called two phases anymore, they have
no electrical engineering answer, no definition, it's just that they
say it isn't. Change the phase angle
from 90 to 95, would it still be two phases? Why when it reaches 180 is
it no longer two phases? When it's at 185, would it be two phases again?

The argument Wbahn makes about a single shaft generator, instead of
supplying 3 phase, make one that supplies 2 phases, at the 90
deg if you like. Two windings, differing by 90 deg, supplying two
hots with a common neutral. Would that be two phases? If not,
why not? And if yes, then why isn't it two phases if I change the
phase angle to 180? If you agree that there are two phases still
there, then that is indistinguishable from the split-phase service
that enters your house. It's all about semantics and you have to
start with the definition of phase. Phase is simply the relationship
between two periodic waveforms.



Here, from MIT, an introduction to power systems, where they start out
with the simple case of a power system with two phases.
Note it's only about two voltage sources connected to two
loads, with two voltage sources that can be at any phase angle.
Nothing about where the voltage source originated from or what the phase angle
is. Nothing about magic happening at 180 degrees, where it's no longer
a two phase system. It's the completely general electrical engineering
case of what defines a two phase power system and how you analyze it.

https://ocw.mit.edu/courses/electric...061S11_ch3.pdf

Make those two voltage sources be the two sides of the transformer on the
pole at your house and it;s the split-phase service that serves your house.







Where you ground that does not change the number of phases.
In fact 3 phase center tapped delta is just your regular single phase
center tapped transformer connected to a delta primary with another
transformer (or two) providing the 3d phase.
OTOH if you corner grounded that delta you would have 2 (hot)
ungrounded conductors and a neutral with 2 pole breakers but it is
clearly still 3 phase.
Two phase is a totally different breed of cat with 2 phases (4 wires)
90 degrees out of phase. This will usually be 2 transformers center
tapped with the center taps grounded (5 wire).
Split phase is a type of motor winding, perhaps the most common for AC
compressors and other applications that use a start capacitor and no
run capacitor. The "phase" is "split" by a start winding 90 degrees
out of phase with the run winding.

How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.


It is single phase. There is only one secondary winding derived from a
single phase primary. The fact that you center tap that winding and
ground that tap does not magically add a phase.

Yes it does, it creates two voltage sources that are 180 deg out of
phase with each other. Why didn't you address the example in that other
forum? I take two single winding generators, connect them on a single
shaft at the power station. One winding is 180 deg out of phase with
the other, they share a common neutral. Now you have two windings,
does that make it two phase?




I suppose the unknowing can call it anything they want but
professionals call your typical home service 120/240 single phase.

Do you ever read what I post? From my first post:

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

So, I really don't understand the problem here.

And then we heard from someone who at least thinks he's a *professional*,
Ed's Electric, saying:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."


I provided links to Siemens, Square D, etc. where they call their panels used
for split-phase service "single phase". Funny I didn't see you correcting
that guy, but here you are all over me, when I agreed that I would CALL IT
split-phase service, because that most accurately describes what it is.
I've said I would not call it two
phase service, because that is not the convention. But that doesn't change
how you ANALYZE it or what's there. This is like arguing that you have
to only describe what we commonly call tissues as Kleenex. Or maybe as
"tissues", that you can't describe them as a very soft, thin paper product
that;s made from trees and used to blow your nose. I'm sure there are
industry specs, details that more accurately describe tissues too, if
you look into it. So, we can't say that tissues are really that, you
can only say Kleenex because that's what the most common used term is?
It's exactly what the poster in that other forum said, it's a question
of semantics.



If I used your logic, a string of Christmas tree lights is "100 split
phases" because I would see a separate little 1.2v wave form across
each of the 100 bulbs on a scope and each one would be 180 degrees out
of phase from the bulb on the other side of the common lead on the
scope.

If you define what the voltages you're looking at in that circuit,
the polarity, V1 across bulb one, V2 across bulb two, V3 across
four bulbs, etc, you could attach a scope and show the various
waveforms. Some would be 1.2V, some would be 4.8V, some would
have one polarity, some would have the other depending on how
you defines the polarity of the measurement points and you could display
them on a scope. You could do it for a class in electrical basics.
Then ask the class to analyze the relationships of those waveforms on
a test. If a student was asked about your two bulb example, to
explain what he sees in the picture from the scope and he answered:

Both are 60 hz sinusoidal waveforms, both are 1.2V, one is 180 degrees
out of phase with the other, is he wrong? Is that an incorrect answer?


And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't.

Then why didn't you correct Ed's Electric when he said that professionals
never call it single phase? Instead you winked at him.


They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.
I really don't care anymore. You can sound stupid if you want, your
choice but 120/240 is single phase to the people who do this for a
living. It is only homeowners and hacks who call it anything else.

Guess the folks at Siemens surge protection, which is part of their
power business must be hacks:

https://w3.usa.siemens.com/powerdist...rst-surge.aspx

You are he
Siemens USA
Power Distribution
Product Portfolio
Surge Protection
FirstSurge„¢

Features & Benefits
UL 1449 Listed, Type 2, Surge Protective Device (SPD)

Rated for 120/240 split phase panels up to 400A

Surge Current Capacities:
- 60,000 A
- 100,000 A
- 140,000 A

3-stage commercial grade notification

These folks who make power conversion products are stupid too?

http://www.samlexamerica.com/support...Circuit s.pdf

120 / 240 VAC SINGLE
SPLIT PHASE &
MULTI-WIRE BRANCH
CIRCUITS
Excerpt from G4 InverCharge
Series Manual

1.1 Service Entrance Panel For 120 / 240 VAC Split Phase AC Power Distribution
Fig. 1 below illustrates the residential 120 / 240 VAC, Single Split Phase, 3- Pole, 4 Wire Grounding System, which was inherited from Edison's
early DC distribution networks.
120 / 240 VAC Split Phase Electrical power from the utility (called Service)is fed through an electrical power meter to a load center / breaker panel
for further distribution. This panel is called the Service Entrance Panel. This panel normally has the following components:

The center-tapped configuration of the secondary side of the Distribution Transformer provides following voltages to the Service Entrance Panel:
€¢ 120 VAC between the Hot Leg L1 (Phase A, Red wire) and the grounded, center tapped Neutral (White wire). The oscilloscope trace of the
voltage waveform between the Hot Leg L1 and Neutral shows the voltage rising in the Positive direction at the start of the waveform
€¢ 120 VAC between the Hot Leg L2 (Phase B, Black wire) and the grounded, center tapped Neutral (White wire). Please note that the
corresponding oscilloscope trace of the voltage waveform between the Hot Leg L2 and Neutral shows the voltage rising in the Negative
direction at the start of the waveform. This indicates that the two 120 VAC voltages are 180 degrees out of phase


I agree the panel makers that I saw all do call it single phase.
Which I have no problem with either, because I'm not arguing about
what it's called. That it's derived from one phase of what comes out
of the power plant, I agree, I'm fine with calling it single phase or
split phase. I'm just saying that doesn't mean that it doesn't look
and act just like a two phase, 180 system.

On Wed, 25 Jul 2018 17:30:00 -0700 (PDT), trader_4
wrote:

On Wednesday, July 25, 2018 at 2:04:26 PM UTC-4, wrote:
On Wed, 25 Jul 2018 08:39:37 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:53:33 PM UTC-4, wrote:
On Tue, 24 Jul 2018 06:53:13 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 7:43:54 AM UTC-4, Bubba wrote:
On 7/24/2018 5:45 AM, trader_4 wrote:
How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.

Grab a dual-trace oscilloscope.

Connect the Scope Common lead to transformer L1

Connect Scope Trace 1 lead to the transformer center tap

Connect Scope Trace 2 lead to transformer L2


You'll observe two screen traces in perfect sync that vary only in amplitude.Â* Only a Hillary voter would mistake it for two-phase.

Did you read the link I posted to the discussion on that other forum?

https://forum.allaboutcircuits.com/t...-phase.105861/

The group moderator, Wbahn posted this:

Take two generators built on a single shaft (the same way that three-phase generators are built on a single shaft) so that you get two 120VAC outputs that are 180 degrees out of phase. Would it be reasonable to call this two-phase power?

Bubba, what's your answer?



Now run them to a house and tie them together so that you have 120VAC between the common and either of the other lines and 240VAC between the two lines. Would it still be reasonable to call this two-phase power?

Bubba?



Could you tell the difference between that situation and the one in which the wires coming to the house are from a center-tapped transformer?

Bubba?


If not, then wouldn't it be reasonable to use the same name for either?
(that was Wbahns final question)

Bubba?


And what he described would still show exactly the same thing on the scope
as the test you described. In all the above, if we changed the phase
difference to 90, would it then be two phase? How about to 179 deg?
In engineering we don't make it up case by case, we analyze the general
case. 180 is just one special case, where it's easy to generate two
voltage sources that are 180 deg out of phase with each other. Or go
take a look at the MIT electrical engineering course in power systems
where they show the mathematics of what
they call two phase power. There are simply two voltage sources
driving two loads. They do the analysis for a 90 deg phase difference,
but you could just as well do the same analysis for a difference of 70
degrees or 180 degrees. The same analysis, the same math applies,
because to the system, it is the same thing.

It's like Wbahn says, it's a matter of semantics and convention.

If you feel differently, then give us your definition of two phase,
3 phase, and N phase power and show us why split-phase is not also
two phases? The only way I see it's not would be to rule that special case
out by *definition*, which is back to the semantics. In that case,
if you can site the electrical body, authority, organization that
has done that, I'm sure we'd all like to see it.

From your discussion group
"So I would put forward the argument that the secondary is a center
tapped transformer providing 120v each side of the center(with center
hard wired to "earth"and providing the "neutral connection") and 220v
across the whole winding. This does NOT constitute a "2 phase" system"

I didn't say there were not others there arguing the other side.
Funny thing though, none of these "professionals" are able to define
what single phase, two phase, three phase, N phase power means.





Don't let electronIC engineers confuse the terminology used by
electricAL professionals. We use specific terminology to avoid
confusion and perhaps save lives. Homeowners and electronics geeks can
call things whatever they want but they only sound stupid when they
talk to the people who do this stuff for a living.



Are you sure you want to now resort to disparaging electronic engineers
as not professional and stupid? Funny I didn't see you ripping into
this alleged "professional", Ed's Electric that posted:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."

You gave him a wink. I guess that was before you saw the links I provided
to Siemens, Square D, that show they call their panels single phase.
That;s what they call them in the product catalog, in the index, etc.
Doh!



Your reference to the panel descriptions confirm what we say.
There are no "split phase" panels, nor are they calling any of them "2
phase". They sell single phase panels and 3 phase panels.

Who;s the "we". Ed's Electric posted that no professional would
ever call it single phase. And you appeared to agree with him,
you gave him a wink.

Again, in my very first post, I said I would
not call them two phase either. But what they are called and what is
there, what you see, how you analyze it are not one and the same.

Here, I found the presentation I referred to. It was made by a power
system engineeing professor with a career going back to the 60's.
He consults on power system, the presentation was made at a power engineering
conference and it's published by the IEEE. He last worked for Milsoft
Utility Solutions, that does work for power utilities. He doesn't
sound like a stupid guy or a homeowner.

https://ieeexplore.ieee.org/document/4520128/

Abstract:
Distribution engineers have treated the standard "singlephase" distribution transformer connection as single phase because from the primary side of the transformer these connections are single phase and in the case of standard rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we
are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Which now brings into focus the reality that standard 120/240 secondary systems are not single phase line to ground systems, instead they are three wire systems with two phases and one ground wires. Further, the
standard 120/240 secondary is different from the two phase primary system in that the secondary phases are separated by 180 degrees instead of three phases separated by 120 degrees. What all of this means is that analysis software and methods must now deal with an electrical system requiring a different set of algorithms than those
used
to model and analyze the primary system. This paper will describe the modeling and analysis of the single-phase center tap transformer serving 120 Volt and 240 Volt single-phase loads from a three-wire secondary.

W. H. Kersting
Milsoft Utility Solutions, USA
W. H. Kersting (SM'64, F'89, Life Fellow 2003) was born in Santa Fe, NM. He received the BSEE degree from New Mexico State University, Las Cruces, and the MSEE degree from Illinois Institute of Technology. He joined the faculty at New Mexico State University in 1962 and served as Professor of Electrical Engineering and Director of
the Electric Utility Management Program until his retirement in 2002. He is currently a consultant for Milsoft Utility Solutions. He is also a partner in WH Power Consultants, Las Cruces, NM.


And he's saying pretty much what I'm saying, that yes it's derived
from a single phase, center tapped transformer, but to correctly
analyze it, model it, you treat it as having two phases. Note, he
didn't say to call it two phase power, neither did I.




As for electronic engineers, they simply use different terminology.
They look at things from a different perspective. You will also find
the voltage drop charts they use are different too. It doesn't mean
they use different copper or wire sizes. They just apply different
conditions when they rate the wire. Electronics people generally make
lousy electricians. I have lived in both worlds and there is a vast
cultural divide between them,.

I have defined single phase to you several times but let's try it
again. It is a system derived from a single secondary winding of a
transformer. (or a single rotating field in a generator/alternator
stator).

So, if I create the generator example where I use two windings in
the generator 180 out of phase on a single shaft, share a common
neutral, that's not single phase because it has two secondary windings?
I don't see the number of windings being the issue.


The fact that you ground the center tap of that secondary
does not change a thing as far as the number of phases in concerned.
There is still one sine wave generated (a single phase) and that does
not change no matter where you stand to look at it.

I agree that there is only one sine wave generated. What I don't get
and what you haven't explained is why if coming out of the generator
you had two hots 90 deg out of phase, that's two phase. I asked, but
never got answered from anyone here, supposed it's 170 deg instead?
Is that still two phase? If it's 190 deg is it two phase? Why if
it's 180 is it suddenly not? That's the problem. Science and engineering
likes rules, laws, explanations that fit the general case. And 180
would just seem to me to be one case of all the possible two phase
possibilities. And how exactly you generate it doesn't matter to
the box it's entering or how you analyze it. You can see that in
the MIT example two, they just used two ideal voltage sources, that
in their case were 90 degrees out. But you could use the same model,
same math to *analyze* 120 deg, or (oh no), 180 couldn't you?



I agree after looking more at those panel makers, that they do use the term single phase, but other power system component manufacturers also call it split-phase, including other divisions of the same power system component
manufacturer, eg Siemens




3 phase is derived from 3 separate secondary windings (although you
can delete one and it still works) with three distinct sine waves, 120
degrees out of phase with each other. It is necessary to start with a
3 phase primary too. That can be grounded at the center tap of one
transformer in a delta configuration, at the end tap of two adjacent
transformers of a delta configuration or at the end tap of all three
in a wye configuration.
You can even leave that ungrounded, typically as a delta.
It is still always going to be 3 phase.
Anything derived from a single secondary winding will be single phase,
center tapped or not.

2 phase is derived from 2 windings, 90 degrees out of phase with each
other.

But again, that's not what we're talking about. That is the historical
case of what it once was. I think you will admit they didn't have to
make it 90, suppose it was 100 or 70? Would that still be two phase?
So, what's so special, so different that 180 suddenly can't be analyzed,
looked at as consisting of two phases? Yes it's a trivial case, but if
179 or 181 can be called two phase, then why not 180?

It is still single phase, it will always be single phase.
Where you happen to be standing when you look at that sine wave may
change but as soon as you hook up 2 sources derived from a single
phase input, you end up with one sine wave when you look at it from
end to end. Changing your view might make it look different but it is
still one sine wave.

BTW you still have not shown me a panel manufacturer saying split
phase. They may say split bus but that is a whole different thing,
pretty much out of use when we stopped using fuses.

I am not sure what the professor is trying to "model" with his math
but that does not change what he is looking at.

You can say anything you want, just be aware professions in the
electrical trades will snicker when they hear you call 120/240
anything but single phase. Folks in the inspector community also shun
the word phase to describe the ungrounded conductors in a single phase
system because they deal with an electrical code that is adopted as
law and in laws, words matter.

On Wed, 25 Jul 2018 17:33:57 -0700 (PDT), trader_4
wrote:

On Wednesday, July 25, 2018 at 1:25:32 PM UTC-4, wrote:
On Wed, 25 Jul 2018 08:14:37 -0700 (PDT), trader_4
wrote:

On Tuesday, July 24, 2018 at 12:41:18 PM UTC-4, wrote:
On Tue, 24 Jul 2018 02:45:45 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 10:14:18 PM UTC-4, wrote:
On Mon, 23 Jul 2018 17:47:02 -0700 (PDT), trader_4
wrote:

On Monday, July 23, 2018 at 8:24:43 PM UTC-4, wrote:
I've never seen a two-phase residential panel at lowes or home depot.Â* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


OK, It has been 45 years since I have worked as an electrician. Perhaps the proper term should be dual phase or split phase. Does that work for you? I really didn't expect I'd be waking anyone up by responding to a 7 year old post.

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

I even found a presentation a power industry engineer made at
a conference where he made the case that to correctly analyze a split-phase
system you have to treat it like what it is, a system with two phases.

The other argument is that if I start with a 3 phase system going into
a building, everyone agrees that there are 3 phases there, right? You can see
them on an oscilloscope. Now let;s remove one. How many phases now?
Two. Now instead of the phases being 120 apart, let's move one so that
they are 180 apart. How many phases now? Two. And if you look at it on a
a scope, it looks exactly like a split-phase gsystem going into the
same building and it behaves exactly like it. Electrically you can't
distinguish one from the other, they are the same thing.

That's my case, others will probably draw different conclusions.

There is single phase, 2 phase (that I doubt anyone here has ever
seen) and 3 phase. If you only use 2 legs of a 3 phase circuit, it is
single phase.

You have to start with the electrical engineering
definition of phase. It's simply the relationship between two periodic
waveforms. That's how we got the term three phase power to begin with.
It's based on the fact that the power is being generated as three separate
waveforms which are separated by 120 degrees.

Here is a good discussion going back and forth:

https://forum.allaboutcircuits.com/t...-phase.105861/


I agree with Wbahn, the group moderator there, he's saying it's about semantics.
And note whenever anyone is challenged as to why it can't be called two phase,
it all falls back to arguments, like "but two phase was 90 deg phase difference
and it doesn't exist anymore". When challenged along the lines of how you
define phase, why if you change 90 to 180, which is just one of the many
possibilities, it suddenly can't be called two phases anymore, they have
no electrical engineering answer, no definition, it's just that they
say it isn't. Change the phase angle
from 90 to 95, would it still be two phases? Why when it reaches 180 is
it no longer two phases? When it's at 185, would it be two phases again?

The argument Wbahn makes about a single shaft generator, instead of
supplying 3 phase, make one that supplies 2 phases, at the 90
deg if you like. Two windings, differing by 90 deg, supplying two
hots with a common neutral. Would that be two phases? If not,
why not? And if yes, then why isn't it two phases if I change the
phase angle to 180? If you agree that there are two phases still
there, then that is indistinguishable from the split-phase service
that enters your house. It's all about semantics and you have to
start with the definition of phase. Phase is simply the relationship
between two periodic waveforms.



Here, from MIT, an introduction to power systems, where they start out
with the simple case of a power system with two phases.
Note it's only about two voltage sources connected to two
loads, with two voltage sources that can be at any phase angle.
Nothing about where the voltage source originated from or what the phase angle
is. Nothing about magic happening at 180 degrees, where it's no longer
a two phase system. It's the completely general electrical engineering
case of what defines a two phase power system and how you analyze it.

https://ocw.mit.edu/courses/electric...061S11_ch3.pdf

Make those two voltage sources be the two sides of the transformer on the
pole at your house and it;s the split-phase service that serves your house.







Where you ground that does not change the number of phases.
In fact 3 phase center tapped delta is just your regular single phase
center tapped transformer connected to a delta primary with another
transformer (or two) providing the 3d phase.
OTOH if you corner grounded that delta you would have 2 (hot)
ungrounded conductors and a neutral with 2 pole breakers but it is
clearly still 3 phase.
Two phase is a totally different breed of cat with 2 phases (4 wires)
90 degrees out of phase. This will usually be 2 transformers center
tapped with the center taps grounded (5 wire).
Split phase is a type of motor winding, perhaps the most common for AC
compressors and other applications that use a start capacitor and no
run capacitor. The "phase" is "split" by a start winding 90 degrees
out of phase with the run winding.

How you generate it doesn't matter. When this came up last time, I
even gave you a presentation made by a power engineer at a power industry
conference, about how split-phase service needs to be analyzed as a
two phase system, because that is actually what it is. I believe it
was also published, because I found it online. I don't think he got
laughed out of the room, but at the very least it was a power industry
source that said exactly what I'm saying. I just looked for it again,
couldn't find it. I'll look again later.


It is single phase. There is only one secondary winding derived from a
single phase primary. The fact that you center tap that winding and
ground that tap does not magically add a phase.

Yes it does, it creates two voltage sources that are 180 deg out of
phase with each other. Why didn't you address the example in that other
forum? I take two single winding generators, connect them on a single
shaft at the power station. One winding is 180 deg out of phase with
the other, they share a common neutral. Now you have two windings,
does that make it two phase?




I suppose the unknowing can call it anything they want but
professionals call your typical home service 120/240 single phase.

Do you ever read what I post? From my first post:

We went through this round and round a few years ago. I was somewhere close
to your position. I said something along the lines that there are in fact
two phases present, 180 degrees apart. But that they are derived from one
of the three phases coming down the street and commonly referred to as
split-phase. But when you spit-something, what do you get? Two things.
I wouldn't call it a two phase panel though, that's not the common term
for it. But it is very common to refer to each of the hots as a phase.

So, I really don't understand the problem here.

And then we heard from someone who at least thinks he's a *professional*,
Ed's Electric, saying:

"No, professionals call it single-phase. Unless you want people to think you voted for Hillary, you should use the proper terminology."


I provided links to Siemens, Square D, etc. where they call their panels used
for split-phase service "single phase". Funny I didn't see you correcting
that guy, but here you are all over me, when I agreed that I would CALL IT
split-phase service, because that most accurately describes what it is.
I've said I would not call it two
phase service, because that is not the convention. But that doesn't change
how you ANALYZE it or what's there. This is like arguing that you have
to only describe what we commonly call tissues as Kleenex. Or maybe as
"tissues", that you can't describe them as a very soft, thin paper product
that;s made from trees and used to blow your nose. I'm sure there are
industry specs, details that more accurately describe tissues too, if
you look into it. So, we can't say that tissues are really that, you
can only say Kleenex because that's what the most common used term is?
It's exactly what the poster in that other forum said, it's a question
of semantics.



If I used your logic, a string of Christmas tree lights is "100 split
phases" because I would see a separate little 1.2v wave form across
each of the 100 bulbs on a scope and each one would be 180 degrees out
of phase from the bulb on the other side of the common lead on the
scope.

If you define what the voltages you're looking at in that circuit,
the polarity, V1 across bulb one, V2 across bulb two, V3 across
four bulbs, etc, you could attach a scope and show the various
waveforms. Some would be 1.2V, some would be 4.8V, some would
have one polarity, some would have the other depending on how
you defines the polarity of the measurement points and you could display
them on a scope. You could do it for a class in electrical basics.
Then ask the class to analyze the relationships of those waveforms on
a test. If a student was asked about your two bulb example, to
explain what he sees in the picture from the scope and he answered:

Both are 60 hz sinusoidal waveforms, both are 1.2V, one is 180 degrees
out of phase with the other, is he wrong? Is that an incorrect answer?


And note I've asked others here to give their definition of single phase,
two phase, three phase and N phase power. Tell us how split-phase isn't
really two phase, using your definition. So far, no one has been able to
do it.

I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't.

Then why didn't you correct Ed's Electric when he said that professionals
never call it single phase? Instead you winked at him.


He said "No, professionals call it single-phase. Unless you want
people to think you voted for Hillary, you should use the proper
terminology."
Punctuation matters too.

Note the period between "No" and the next sentence,

They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.
I really don't care anymore. You can sound stupid if you want, your
choice but 120/240 is single phase to the people who do this for a
living. It is only homeowners and hacks who call it anything else.

Guess the folks at Siemens surge protection, which is part of their
power business must be hacks:

https://w3.usa.siemens.com/powerdist...rst-surge.aspx

You are he
Siemens USA
Power Distribution
Product Portfolio
Surge Protection
FirstSurge„¢

Features & Benefits
UL 1449 Listed, Type 2, Surge Protective Device (SPD)

Rated for 120/240 split phase panels up to 400A

Surge Current Capacities:
- 60,000 A
- 100,000 A
- 140,000 A

3-stage commercial grade notification

These folks who make power conversion products are stupid too?

http://www.samlexamerica.com/support...Circuit s.pdf

120 / 240 VAC SINGLE
SPLIT PHASE &
MULTI-WIRE BRANCH
CIRCUITS
Excerpt from G4 InverCharge
Series Manual

1.1 Service Entrance Panel For 120 / 240 VAC Split Phase AC Power Distribution
Fig. 1 below illustrates the residential 120 / 240 VAC, Single Split Phase, 3- Pole, 4 Wire Grounding System, which was inherited from Edison's
early DC distribution networks.
120 / 240 VAC Split Phase Electrical power from the utility (called Service)is fed through an electrical power meter to a load center / breaker panel
for further distribution. This panel is called the Service Entrance Panel. This panel normally has the following components:

The center-tapped configuration of the secondary side of the Distribution Transformer provides following voltages to the Service Entrance Panel:
€¢ 120 VAC between the Hot Leg L1 (Phase A, Red wire) and the grounded, center tapped Neutral (White wire). The oscilloscope trace of the
voltage waveform between the Hot Leg L1 and Neutral shows the voltage rising in the Positive direction at the start of the waveform
€¢ 120 VAC between the Hot Leg L2 (Phase B, Black wire) and the grounded, center tapped Neutral (White wire). Please note that the
corresponding oscilloscope trace of the voltage waveform between the Hot Leg L2 and Neutral shows the voltage rising in the Negative
direction at the start of the waveform. This indicates that the two 120 VAC voltages are 180 degrees out of phase


I agree the panel makers that I saw all do call it single phase.
Which I have no problem with either, because I'm not arguing about
what it's called. That it's derived from one phase of what comes out
of the power plant, I agree, I'm fine with calling it single phase or
split phase. I'm just saying that doesn't mean that it doesn't look
and act just like a two phase, 180 system.

VIJAY SHARMA is not an electrician and he seems to live in India. I am
not sure I think his "white paper" accurately reflects American
nomenclature for circuits here. Just the fact that he calls "2 phase"
a "180 degree system" seems to show he may not really understand what
he is talking about all the time.
"2 phase" has a 90 degree phase angle difference.

On 07/25/2018 08:30 PM, trader_4 wrote:
Again, in my very first post, I said I would
not call them two phase either. But what they are called and what is
there, what you see, how you analyze it are not one and the same.


The second phase you are reporting is a fake, which doesn't surprise me.Â* There's a lot of fake news out there.


Imagine a secondary transformer winding with a continuously variable location tap. You attach an oscilloscope probe to the tap and attach the scope common to L1.

Starting with the tap at the beginning of L1, slowly slide the tap along the secondary winding and note the scope trace.Â* You will see the amplitude change but the phase angle will remain constant.

I repeat, no matter where you position the tap along the winding, the phase angle stays the same.Â* Single phase.


Stop reporting fake science!

On 07/25/2018 02:28 PM, Bubba wrote:
On 7/25/2018 1:25 PM, wrote:
I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't. They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.

The fact that the word "phase" applies to one system (that one with the
phases 90 degrees apart) doesn't mean it doesn't apply to another.

I really don't care anymore. You can sound stupid if you want, your
choice but 120/240 is single phase to the people who do this for a
living. It is only homeowners and hacks who call it anything else.

If a the transformer secondary had 2 equally spaced taps, would LymeBoi
call it 3-phase

Consider that you can only have one neutral.

On 07/26/2018 09:58 AM, Sam E wrote:
On 07/25/2018 02:28 PM, Bubba wrote:
On 7/25/2018 1:25 PM, wrote:
I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't. They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.

The fact that the word "phase" applies to one system (that one with the phases 90 degrees apart) doesn't mean it doesn't apply to another.

I really don't care anymore. You can sound stupid if you want, your
choice but 120/240 is single phase to the people who do this for a
living. It is only homeowners and hacks who call it anything else.

If a the transformer secondary had 2 equally spaced taps, would LymeBoi call it 3-phase

Consider that you can only have one neutral.


Or do we even need a neutral?Â* Does a 3-phase delta system have a neutral?

posted for all of us...



On Tue, 24 Jul 2018 15:26:18 -0400, Tekkie®
wrote:

trader_4 posted for all of us...



On Monday, July 23, 2018 at 5:02:39 PM UTC-4, Walt's Electric wrote:
On 7/23/2018 7:04 AM, wrote:
If this were a 2 phase panel, such as almost all residential panels are, it would have 2 hot lines and one neutral. In this case if the loads are balanced the current in the neutral will be zero. With unbalanced loads the current in the neutral is the difference between the 2 hot lines. Because the current in one is 180
degrees out of phase with the other the current from one cancels out the current from the other. Best practice is to try to
keep the loads balanced as much as possible.

I've never seen a two-phase residential panel at lowes or home depot..* Since they're so common, would you provide a link to one at homedepot.com or lowes.com?


Oh no, here we go again.

Exactly...

I guess we are ready for the old NEMA 5-15 ground pin orientation
argument again. ;-)

Let's hope Oren will post his picture on how to do it!

--
Tekkie

On 07/26/2018 12:12 PM, Buck wrote:

[snip]

Consider that you can only have one neutral.


Or do we even need a neutral?Â* Does a 3-phase delta system have a neutral?
OK. No more than one neutral. That includes the delta with no neutral.

--

On Thu, 26 Jul 2018 08:58:52 -0500, Sam E
wrote:

On 07/25/2018 02:28 PM, Bubba wrote:
On 7/25/2018 1:25 PM, wrote:
I can't tell you in simple terms why a nectarine isn't a peach either
but they are not the same.
Did you see the term "split phase" in those panel manufacturer's
descriptions? I didn't. They had single phase and 3 phase. They didn't
say "2 phase" either since that is really a thing, having absolutely
NOTHING to do with 120/240.

The fact that the word "phase" applies to one system (that one with the
phases 90 degrees apart) doesn't mean it doesn't apply to another.

Simply choosing to call ungrounded conductors "phases" does not make
it so. This came from 3 phase where each ungrounded conductor does
represent a phase. When you are in single phase, it doesn't.
People are simply trying to rationalize that when you take a single
phase 240v circuit and cut it in half, you now seem to have 2 phases.
If I walk half way up a ramp, it may look like 2 ramps, one going up
and one going down but it is still just one ramp.
Even when you gang together 2 or more sources, in series, once they
are connected, they are still just one, single phase system and when
you look at it end to end, it will just be one sine wave.

On Thu, 26 Jul 2018 13:12:26 -0400, Buck wrote:

Consider that you can only have one neutral.


Or do we even need a neutral?Â* Does a 3-phase delta system have a neutral?

Yes or no, depending on whether we ground it or not. That is one
reason why the NFPA really resisted using the term neutral and prefers
"grounded conductor". In a center tapped 240/120 delta, the grounded
conductor is a neutral, handling the unbalanced load from the center
tapped transformer but in corner grounded delta there is no more
unbalanced current on the white wire than on any ungrounded conductor.

There is also ungrounded delta, used in some critical industrial
applications because of it's fault tolerance and also in those high
voltage transmission lines. The medium voltage distribution going down
your street (13kv - 26kv) may be delta but it is more likely to be
wye. If there is only one primary, it is certainly wye.
This is typical wye distribution
http://gfretwell.com/electrical/transformer.jpg