On Tuesday, November 26, 2013 3:26:15 PM UTC-5, wrote:
On Tue, 26 Nov 2013 11:49:22 -0800 (PST), TimR

wrote:



After bud's excellent explanation, we can see that Danny is almost right..



The ground IS a parallel path for return, but most of the current will flow along the neutral wire.



If there's not a neutral wire, then..........no don't go there. Yet.



Back to that single phase feeding the house from the transformer secondary for a second.



The center tap of that transformer is bonded to ground. That gives us a zero reference. But that technically is not necessary. Your house would work fine without it. Your oven would still "see" 240 volts and your lights 120. The problem is you might have a voltage difference between some of your equipment and ground.



But transformers are not limited to one tap. This secondary could easily be tapped at 60, 120, 180 and 240 volts referenced from tap to "low" terminal.



Do I now have 4-phase power? Do I have four legs out of phase?



At a certain point we have to stop all of the "phase" BS and just say

this is single phase. Anything else is just wrong. Split phase refers

to the way some motors are wound and two phase is something else

altogether (4 wires with 2 phases 90 degrees out)

Standard 120/240v service is single phase that just happens to be

grounded on the center tap.

Tell that to the IEEE power engineers. From the absract of a paper presented
at a recent IEEE conference of power engineers:

http://ieeexplore.ieee.org/xpl/artic...number=4520128

"Distribution engineers have treated the standard "singlephase" distribution transformer connection as single phase because from the primary side of the transformer these connections are single phase and in the case of standard rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Which now brings into focus the reality that standard 120/240 secondary systems are not single phase line to ground systems, instead they are three wire systems with two phases and one ground wires. Further, the standard 120/240 secondary is different from the two phase primary system in that the secondary phases are separated by 180 degrees instead of three phases separated by 120 degrees."


I'm still waiting for you to explain your definition of the word phase.
Should be easy, as it's a very basic engineering term. If you know what
it is, then why can't you define it?