On Tue, 30 Jan 2007 21:01:59 -0500, wrote:

On Tue, 30 Jan 2007 13:54:52 -0600, Mark Lloyd
wrote:

Actually most sub panels do use 2 hot legs (240v and 120v),
don't confuse that with the term, "single phase". That is really one
"phase", center tapped to give you two 120v circuits.

It can be one phase or two, depending on your reference point.
However, either way it's not three.

This is still singe phase. The fact that it is center tapped does not
add a phase.

Making that center tap the reference point (which seems logical since
it's grounded) and examining the voltages on the other 2 conductors,
you now have 2 points out of phase with other. 2 phases.

I even looked up the definition of "phase" again. Nothing about it
excludes 180-degree separation.

"Two phase" does exist but most people will never see it.
That has the phases shifted by 90 degrees and uses 4 circuit
conductors..

I haven't really seen it, but have read about it.

That's definitely 2 phase. That does not limit "2 phase" to that. That
would be like saying that the definition of "money" is "$15" (allowing
no other amounts to qualify).

There's also 4-phase, and I have seen that but only for driving
stepper motors.
--
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