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That would be like the 240V circuit of the center tapped transformer yes. It does not have much to do with the relationship between the 2 120V legs created from the center tap.
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A 204vac(rms) CT xfmr is one (single) coil, they add a tap in the center. The single coil has only one dot on it.
It's like taking a tension spring, adding a dot to one end to designate DC coil direction, then stretching the coil in the middle (elastic deformation) enough to clip on a tap wire.
A tap is a voltage divider, nothig more than that. A CT just so happens to be in the center, which yields two 120v and one 240v source.
Add more taps and you get more voltages, the issue for AC is, a tap that is not in the middle will have voltage less than 120v and then on flip cycle more than 120. The Diff at any tap location across 1 full sine cycle ALWAYS = the xrfmr ends, and in this case, 240vac.
(+120v) - (-120v) = 240
(+60) - (-180v) = 240v
(+30v) - (-210v) = 240v
A tap is nothing special, but a CT is kinda the only tap that is user "friendly" when it comes to power delivery to a home.
Europe uses mostly 240c 50Hz, no taps.
120v is "safer" than 240v.
120v has big disadvantage in terms of efficiency, because at same kVA the 120 is wasting a lot more power than 240v is. Eletric batt EV's are way more efficient than gas vehicles, and if we wanted to save on wasted power we should do away with these 240v CT xfrmers and just use 240vac. Toasters, microwaves, etc, would all waste less power if they were using 240v instead of 120v.
Pros & Cons.