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Mr. Luddite

On 3/24/2014 5:40 PM, wrote:
On Mon, 24 Mar 2014 16:53:46 -0400, "Mr. Luddite"
wrote:

I understand and I didn't say it was accurate. However, as the other
poster pointed out there is sometimes some confusion as to what a home
service is called since you *do* have two hot legs 180 degrees out of
phase. The "split phase" isn't a reference to how a motor is wound in
this case. It's a reference to the center tapped, 240v service
producing two hot legs 180 degrees out of phase referenced to neutral.

The terminology used to describe it has been a subject of debate for years.

That is why code officials are trying to straighten it out every
chance they get ;-)

I am not an electrician. I've found over the years that terminology
used in the NFPA codes sometimes differ somewhat from what we use in
engineering even though we are talking the same thing. I also sometimes
found that some industrial applications are not defined or even covered
in the code book. If an issue arose that was questionable I had a EE PE
check it over and stamp the final power and control system drawings.

Last winter I got involved in a project building a performance venue
stage and it's wiring. The building had a dedicated 3 phase power
distribution panel that had previously been used for when the building
had been a large machine shop. I used it to distribute several 120vac,
20 amp feeds to the stage, overhead stage lights, PA system, house
lights, etc., but because I am not up to speed on current code
requirements for things like ground fault protection devices and another
new one that I can't remember the name of, I asked a friend who has been
a licensed master electrician for 26 years to review what my plans were
to make sure I didn't violate any codes and to ensure it was safe to use.

As far as residential house power is concerned, to me it is single phase
(at whatever high voltage is used locally) up to the primary of the
transformer. The secondary has two "hot" legs from the center tapped
transformer that are 180 degrees out of phase with each other referenced
to neutral or ground. In my world that is two phases, "zero" and "180"
relative to neutral or ground. :-)