David Nebenzahl wrote:
On 2/2/2009 6:40 PM Pete C. spake thus:

David Nebenzahl wrote:

The question from the person in Peru about wiring for 230 volts raises a
question: in places that use 230/240 volts for household current (i.e.,
most of the world), how is that power brought into the house?

Here, we have 2 "legs" of 120 volts each (two hots and a neutral)
of opposite phases, so that you can either tap 120 from either leg
or 240 between them.

They aren't "opposite phases", they are opposite polarity as they are
the center tapped (center is neutral) output of a single phase
distribution transformer.

Yes, same phase, opposite polarity. My bad.


I think you were right. The transformer on the power pole produces two
phases from one phase. Because the difference is pi radians, the
polarities will be opposite when polarities exist.