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The US (and CA) runs on 240V as well, it's just split in half for smaller appliances. See requisite Technology Connections video:

* https://www.youtube.com/watch?v=jMmUoZh3Hq4

My stove and clothes dryer are certainly not 120V.

⬐ tjoff

In the same way that 240V countries run on 400V as well then?

⬐ Kirby64

Sort of. Outside of industrial or businesses, my understanding is that it is rare to see multi-phase power (400V) used in power applications. You may get 3 phases into your house, but the phases are used separately (each at 240V) for most things in residential.

⬐ tjoff

Stoves are pretty much always at three phases unless it is something like a small summer-house

Washing machines too I've heard.

⬐ throw0101c

> In the same way that 240V countries run on 400V as well then?

400V is not sent to your home (AFAICT) in 240V-based countries. There is no connection at any box in a typical home where you can connect two wires to get 400V. It could be distributed in three-phase 400V on the street, but most homes do not have three-phases delivered, generally only hot+neutral.

In US/CA homes there are two wires (L1+L2) that give you a 240V, and that 240V is used for larger equipment. There just happens to be a third (N) that allows for 120V as well.

Are there typically any 400V appliances in a (e.g.) EU home?

There's a lot of misconceptions about US electricity. This video does a nice job at pointing out the good and the bad.

https://www.youtube.com/watch?v=jMmUoZh3Hq4&ab_channel=Techn...

There's probably a large overlap between software people and people who subscribe to Technology Connections: https://www.youtube.com/watch?v=jMmUoZh3Hq4

Relevant video: Technology Connections, "The US electrical system is not 120V", where there is a (long) discussion of how the breaker panel works and how you get 240V.

https://www.youtube.com/watch?v=jMmUoZh3Hq4

⬐ teddyh

By the same definition, the European electrical system is not 240V, it’s 380V.

⬐ frosted-flakes

Europe does not have split phase electrical service. Three-phase service is ultimately how the US system works, same as Europe; it's just that entire neighbourhoods or streets will run off a single 240 V phase rather than each house getting all three phases (industrial buildings commonly have three-phase service).

⬐ jacquesm

> Europe does not have split phase electrical service.

This is incorrect in many places. Yes, you will have three phase electrical service pulled right into the distribution panel, but in many places all you will receive is a single phase because only one of the three possible fuses is installed.

If you want three phase hookup you just pay your utility company a small fee, they come out to install the extra two fuses and in some cases they'll upgrade your consumption meter to three phase.

> Three-phase service is ultimately how the US system works, same as Europe; it's just that entire neighbourhoods or streets will run off a single 240 V phase rather than each house getting all three phases (industrial buildings commonly have three-phase service).

In the US plenty of the last leg of the distribution network is single phase, in the EU it is almost everywhere three phase, except for some rural areas in former East block countries. Typically a step down transformer will take the distribution voltage and reduce it to something the residents can use directly, houses are then alternating in which of the three fuses is placed (R/S/T) to ensure relatively even distribution of the load.

Here you see a three phase domestic hookup (for instance because of an electric range):

https://www.superflink.nl/media/wysiwyg/1-of-3-fase-aansluit...

and here a single phase one:

https://www.circuitsonline.net/forum/file/58210/forum-post

In this case the 'S' leg of the transformer is used to power the dwelling.

⬐ frosted-flakes

What you describe is not split phase. Split phase is where one 240V phase is split into two 120V legs offset 180°, with a center-tapped 0V neutral.

⬐ jacquesm

See my comment elsewhere in this thread where I think I pretty much exhaustively treated the subject.

And no, that particular version of 'split phase' is not +120V and -120V, this is not DC that we are talking about. Europe used to have a lot of that kind of split phase but we 'phased it out' to use a cheap pun.

So now the term single phase is used to indicate what you typically get delivered to your house and we don't further subdivide it. This is good because it means you can run much thinner wire due to reduced current. You do get a bigger whack if you accidentally end up touching the phase or if there is an internal short in an ungrounded device that exposes that phase to the outside (this should never happen). In North America 240 V center tapped off a single drop transformer is the norm for residential delivery.

⬐ frosted-flakes

I should have said two 120V legs offset 180°.

⬐ jacquesm

That's accurate. In NL until the 70's we had two levels of delivery, 127V (phase to ground, transformer in 'star' configuration) and 220V (phase to phase, transformer in 'delta' configuration). The latter is interesting because it doesn't actually have a neutral wire at all.

The former was close enough that you could get away with plugging in US or Japanese devices, but if there was anything synchronous in there you'd be out of luck (50 Hz vs 60 Hz). Then 220V became the standard and now it is all 240.

Interesting tidbit: there was so much inertia from older systems that needed upgrading in this that it took until 2004 until the last of it (the 127->220V change) was finally done.

⬐ jacquesm

This is an incorrect interpretation of the differences between the two systems.

In the EU the 380V (now nominally 400V) relates to tri-phase, the 240V to the voltage between a phase and ground.

Tri-phase power in the United States is available to residential consumers and very light industry (say a small farm) at a number of different voltages up to 480V.

The 240V in the united states is between two 'lives' that are both 120V and that are usually delivered on a center tapped transformer with the center being the neutral. Adding those two together gives you the 240V, but it all comes from a single phase, it's just a center tapped transformer with a 240V winding as the secondary.

You can easily see this when you look at your typical drop transformer that will take a 10KV low voltage distribution line to domestic voltages, where three phase power is required you'll see three transformers in a bank, one for each phase. A typical residence will have only one because in North America single phase power is the norm for distribution.

https://www.mytpu.org/wp-content/uploads/wires.jpg

Is pretty typical in NA.

So a typical drop will have a distribution neutral and a single distribution phase going in to the transformer and three wires coming back out: L1, N and L2 with L1 and L2 being the outside legs of the winding. In your distribution panel you then add your residential ground.

⬐ jacquesm

bugfix: the 240V to the voltage between a phase and ground

This is possible, but more likely is a phase-to-phase in a delta configured transformer. In that case there is no ground delivered to the distribution panel, just two phases (or three).

https://m.youtube.com/watch?v=jMmUoZh3Hq4

⬐ colejohnson66

I haven’t watched the video yet, so I don’t know if he addresses this, but: considering many devices with a switching PSU support “universal” voltage, plugging a US style plug into a 220/240V source would probably be fine.

Enjoy https://youtu.be/jMmUoZh3Hq4 .