All that sounds fine, however when you are referring to residential and
commercial electrical services in the US, they are generally referred to as
single phase and three phase



"Mark Lloyd" wrote in message
...
On Wed, 31 Jan 2007 23:11:50 -0500, wrote:


service panels are a 3 wire single phase system. It is very common to
incorrectly refer to this as "two phase". Follow the link for an
explanation. http://en.wikipedia.org/wiki/Split_phase

That does SAY that, but fails to consider that the word "phase"
already has a meaning.

BTW, what definition of "phase" are you using?


I suppose you can call single phase AC two phase you want but it will
only tag you as an amateur around electrical professionals.

Of course it has NOTHING to do with what I want. It has to do with
what the WORD "phase" actually means.

BTW, I never said I don't call it "split phase". I just said it was 2
phase also.

Just to be sure we're still talking about the same thing, it's AC from
a center-tapped transformer secondary with the center tap grounded?

Are you using a definition of "phase" that DOESN'T apply to the
120/240VAC electrical system? What it that definition?

BTW, here is one definition:

************************************************** *******

3. A measure of how far some cyclic behavior, such as wave motion,
has proceeded through its cycle, measured in degrees or radians. At
the beginning of the phase, its value is zero; at one quarter of its
cycle, its phase is 90 degrees (?/2 radians); halfway through the
cycle its value is 180 degrees (? radians), and so on. ? The phase
angle between two waves is a measure of their difference in phase. Two
waves of the same frequency that are perfectly in phase have phase
angle zero; if one wave is ahead of the other by a quarter cycle, its
phase angle 90 degrees (?/2 radians); waves that are perfectly out of
phase have phase angle 180 degrees (? radians), and so on. See more at
wave.

************************************************** ********

Source: American Heritage Science Dictionary (c) 2002

Of course it's a lot easier to understand than to explain.

AC is definitely "cyclic behavior", and when you examine the 2
nongrounded conductors at he same time you see the cycle at 2
different points. You can measure the voltage between the HOT wires of
2 different 120V outlets (120V hot to neutral). You get either 0V or
240V. That's enough to tell you something's going on.

120V is not the same as 120V (measured at different outlets). What's
different about it?
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy