On Friday, December 6, 2013 5:22:39 PM UTC-5, Fred McKenzie wrote:
In article ,

Emma Genius wrote:



Here's what my genius mind came up with.



First I obtained a standard D-cell battery pack that holds 2 batteries in

series.



Next I installed a center tap between the two batteries in the battery pack.



So now I have a series battery pack with three terminals:



L1 is the (-) negative terminal on battery A

N is the center or neutral tap between battery A and B

L2 is the (+) positive terminal on battery B



So to prove I have 2-phase DC, I connected a dual-trace oscilloscope as

follows:



The reference leads from both probes were connected to the center neutral

tap.

Probe A was connected to L1

Probe B was connected to L2



As I expected, the scope showed a 1.5 volt positive phase trace and a 1.5

volt negative phase trace.



Clearly I have 3 volt 2 phase DC.



The only thing left to do is submit my paper to IEEE.



This discussion seems to keep going on, continued from prior identical

threads on other newsgroups. Each person is repeating the same thing

over and over. It is clear that I'm not the only one with too much time

on their hands!



Yes, everyone (should) agree with the basic idea of phase.

Yes, they should, but only a few have even tried to define it.


Yes, the

grids of push-pull tubes are 180 degrees apart in phase, as are the

plates. Yes, the two leads of a simple transformer secondary are 180

degrees apart in phase, regardless of whether there is a center tap or

not.



Not true. If a transformer has only two leads, they are *not* 180 degrees out of phase because there is just a single circuit. You can't see two waveforms
on a scope, because there aren't two.

Going back to what started all this, someone just said that the
two hot legs of a split-phase service are 180 deg apart. krw said
that was flat out wrong, that they are just "opposites" Aside from
the fact that "opposites" is not exactly an engineering term, what
about your push-pull example? Is it not correct to say the output
is 180 degrees apart from the input?




The argument seems to hinge on whether the power grid uses the same

definition of phase. Of course it does. But then you confuse "split

phase" of a 3-phase power system with the obvious fact that a

center-tapped transformer secondary has each side 180 degrees apart from

the other. Big deal.

It's not a big deal. It's just that you then have a 3 wire circuit
with two phases present that are 180 deg apart. You can see it on a
scope.


You are still referring to the one phase of a 3

phase power distribution system, that is split into two voltages by

center-tapping a local distribution transformer.



Who is the you? And just because it's common to refer to something
as one thing, does that make it so? If everyone calls a peanut a
nut, does it make it one? My guess would be that those stuck on
the other side of this call it single phase because the PRIMARY
of the transformer is on a single phase. That doesn't change the
physics of what is on the secondary side. Also, in your experience,
can you cite an example where you split something and still have
just one thing? It is called "split-phase".



I think this discussion is comparable to two political parties refusing

to acknowledge their positions are just two ways of looking at the same

thing. If they agreed, there would be no need for two parties!



Fred

If you believe the last nonsense, I can see why you're totally confused.