In Euro/china power is the 240/250 supplied on one phase. My frame of reference is that we send 120 on single phase conductor. Our 240 is 120 on each of two phases. It seems to me that I have read that Euro/china and actually many other countries 240/250 can't be separated in that way. Any light shone (pun intended)on this question will be greatly appreciated. Yes I am new to this site and value the apparent depth and breadth of knowledge. I have a fair knowledge of electricity but not enough to act like I know stuff. Not on this forum. I have read many of the post. Again thank you for your input.

TOO NOT KNOW ONCE IS UNDERSTANDABLE, TO NOT KNOW TWICE IS LAZINESS. )

 

American household standard is still single phase.

Its just split with the center tap of a 240 VAC circuit connected as the common/earth ground instead of having one end as the common/earth ground for that set of lines.

 

Yes, N.A., Both Canada & US is single phase 240 with earth grounded centre tap declared as neutral, most of the rest of the world is also 240v single phase, except originating from a one phase of a 3phase supply, one phase and a star point grounded neutral.
Some of Asia such as Japan is 100v and 200v standard.
Max.