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wrote:
On Mon, 27 Dec 2004 12:21:18 -0500, "Pop" wrote:

Lil' Dave wrote:

"Tekkie" wrote in message
l.net...

Lil' Dave posted for all of us....

...

I looked at the "flower pot" that feed the power pole from the
transformer pole. There are 3 wires. 1 wire is not
insulated. 2
wires are insulated. These wires go to the meter on the power
pole.
Explain 3 phase power entry point when there are only 2 power
wires... I don't need a search engine to determine the number
of
phases provided by the power company at this location. A
common
neutral or ground is not another phase by any measure.

...

Everybody's wrong: Normal household power is called "split
phase", where there will be 3 wires, two hot, and one neutral.
Evan many electricians will call it 2-phase, but it's not because
of the angular difference in split phase which is 180 degrees.
Three phase is more precisely used in power distribution grids,
factories and other high voltage situation, now low voltage as in
residential power. 120/240 is considered "low" voltage in this
arena.
Try looking up "split phase" +power" . When reading, one
must be careful WHAT he is reading about, when you get into 1, 2,
3, etc. phase situations and star and delta methodologies.

Quote:
Split phase

From Wikipedia, the free encyclopedia.

Split phase is a mains electrical supply system mainly used in
America (where it is usually and incorrectly referred to as two
phase). It is used occasionally in the UK in distribution
situations where only two 11 kilovolt phases are available, but
it is rarely taken into buildings.

A transformer providing split phase has a single phase input, and
the output is centre-tapped with the neutral on the centre tap.

This means that there are two phase conductors both equidistant

from the neutral. Therefore (provided the balance is good),

appliances can be directly supplied with the normal voltage with
some of the advantages of higher voltages, such as smaller cables
and/or lower losses. It also means that appliances can be
supplied that need double the normal voltage, so it is WIDELY
USED for high power or European equipment in the USA.

Thank you for explaining it, I usually get messed up since my
background is from the 3-phase industrial shop.

But to be an antagnoist, since the phases are truely opposite of each
other(180 degrees), then it can be referred as two-phases, since they
aren't in phase with eachother.

Sorry antagonist. That is incorrect. The "phases" as you describe, are
still in sync with each other. Their voltage potential from
neutral/center tap is indeed *opposite*, but still "in phase".

--
Tony
I don't need an anti-static workplace... since I have no potential.