On Mon, 10 Aug 2015 19:23:55 +0000 (UTC), John McCoy
wrote:

krw wrote in news:lsmhsah7vnp9eh2vp4utnonsv59pb7ai3m@
4ax.com:

On Mon, 10 Aug 2015 14:53:43 +0000 (UTC), John McCoy
wrote:

phorbin wrote in
:

I don't know nuthin about this but

http://www.leeson.com/TechnicalInformation/sphase.html

From an electrical engineering perspective, that article is
wrong (and it shows how guys like Lew can get confused on
the subject).

All of the motor designs shown there, except for the shaded
pole motor, are split-phase motors. Any single phase motor
with a starting or auxilliary winding is a split-phase motor,
because the phase of the starting/auxilliary winding is not
the same as the main winding. That's why they're called
split-phase motors, because they have two windings with
different phases.

Actually, the shaded pole motor is also a split phase motor. The
shading coil is the other phase. ;-)

Well, in a sense that's correct, altho by extension that
definition would mean all single phase motors are split-phase,
since you have to have something offset from line phase or
they'll never start rotating. It's not the most useful
definition :-)

Yes, you need some offset but it could be a multi-phase (or
DC/universal) motor rather than splitting the one phase. It might be
true that all single-phase induction motors are split-phase. Can't
think of a counterexample right now.

In engineering practice, tho, split-phase means split off
from the line, as opposed to being induced (as is the case
for the shaded pole motor).

That's a distinction that's not universal.