On 09/04/2021 20:39, Andy Burns wrote:
Fredxx wrote:

Â*From a pedantic POV, the USA has 120V between live and neutral. It
can also have 240V or 208V depending on the supply. 208V being from 2
legs of their 3-phase supply.


Not wuite, they have 3-phases in the street but their transformers (pole
pigs) have centre tapped secondary so it gives +110V/N/-110V to the
house, most circuits use a single live (hot) to neutral, but heavy duty
stuff like tumble driers use both hots

https://youtu.be/jMmUoZh3Hq4

1) First all the guy in the video is correct.

2) The voltage is 120V but also 240V or 208V depending on the supply.

https://en.wikipedia.org/wiki/Mains_electricity
"In the United States[14][15] and Canada,[16] national standards specify
that the nominal voltage at the source should be 120 V and allow a range
of 114 V to 126 V (RMS) (ˆ’5% to +5%). Historically 110 V, 115 V and 117
V have been used at different times and places in North America. Mains
power is sometimes spoken of as 110 V; however, 120 V is the nominal
voltage."

3) 208V or 240V is supplied to homes. 240V split either side of
ground/neutral is the most common but many domestic builds simply supply
2 phases and not every home has it's dedicated transformer. It's
obviously cheaper for a one large transformer supply a block of flats
and houses. Many appliances will have a 208/220/240V label. I can find
very little with Google, but this is an article with an explanation:

https://www.researchgate.net/post/Co...r-110-or-220-V

Obviously: 208 = sqrt(3) * 120

HTH