[laumars]

It’s a good design but I disagree that it improves on all the safety features. For starts the child proof safety shutters are still only optional in some regions.

> except the polarity isn't fixed, that's its one theoretical disadvantage

Polarity isn’t fixed on any mains sockets. That’s why the A in AC stands for “alternating”

[wrycoder]

And yet there is a big difference between the hot and neutral conductors in a 120V outlet in the US. The neutral remains close to ground potential, and is actually bonded to earth at the breaker panel.

[laumars]

I’ll admit that my understanding of these things is rather superficial. I might understand more than the average person but that’s not exactly a high bar to set.

However I always understood potential to be different to polarity. And that AC (which, to my knowledge, all electric grids globally carry) is the literal oscillation of polarity. What am I missing/misunderstanding from the GPs post?

[kuschku]

English isn’t my native language, so I mixed up those two terms.

But that’s what I meant, the UK and US plugs (as well as switzerland I think?) theoretically have one pin always be hot, one always be neutral.

With Schuko, you can reverse the plug, and it'll still work, which is on the one hand awesome when you've got a tight space and want more plugs to fit, but can also require higher costs, as you've always got to switch both wires instead of just switching the hot one (although this is best practices everywhere, as you can never know how well the electrician followed specs when wiring your apartment 90 years ago).

[laumars]

Ahh I see. Thanks for the clarification

[wrycoder]

The transformer on the pole delivers 240V rms center tapped, with the center tap being connected to ground at the pole. The center tap wire is actually uninsulated, and the two hots are wrapped around it for support. The center tap is connected to the neutral bus at the breaker panel.

Half the breakers are connected to one hot, and half are connected to the other hot. For 120V you wire hot/neutral to the receptacle, while for 240V you wire hot/hot. (Plus ground, of course.)

In the EU, receptacles are wired hot/hot, and there is no neutral conductor.

[kuschku]

What? That's wrong.

The typical EU configuration:

The transformer delivers a neutral and three phases, in a star configuration.

That means you've got L1, L2, L3, N and GND.

N to any L is 230V, any L to any other L is 380V.

That also means a typical grounded socket has e.g., L1, N and GND, so a neutral and a hot.

A high-power socket or e.g. a stove will have GND, N, L1, L2, L3.

My stove has the oven running on L1 and N in a 230V hot/neutral and the stove at L2 and L3 in a 400V hot/hot configuration.

(Belgium is the exception, having phases at 113V off the center point, so sockets are in hot/hot to get 230V between the phases)