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Comment by aldonius | Hacker News Reader

> I'm also happy to see systems like this that run without exotic water cooling and 240V power.

Always funny to see 240V power described as exotic (or at least exotic-adjacent). It's the standard across practically the entire world except North and Central America!

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They actually distribute 240V in USAmerica, one neutral wire and two opposite-phase 120V wires. Outlets in homes are 120V but wiring 240V is not difficult.

https://en.wikipedia.org/wiki/Split-phase_electric_power

This is different from Europe where we usually distribute 3 phases 130V.

> but wiring 240V is not difficult.

Most homes don't have more than a few 240v circuits, and they are usually always dedicated to a single device. My house has 4: range, oven, drier, water heater, all with only a single outlet. The concept of wiring split-phase 240V is not difficult, but getting 4-conductor 12-gauge wiring run to a new location in an existing building is not exactly easy.

So, the power delivery type/format _isn't_ exotic, but the ability to use it in arbitrary locations in a [residential] building, compared to 120V being in every room (though perhaps not 120V/20A in every room)

I have 4 a well, but in my case it's Range/oven, Dryer, Water heater, and a 240v outlet in my garage that would be great for either recharging an electric vehicle or powering high voltage tools like a welder/plasma cutter.

Sure, but wiring 240v is still not difficult -- even in the States. The physical act of wiring 240v is on par with that of wiring 120v.

3 phases 230v you mean?

> In Europe, three-phase 230/400 V is most commonly used. However, 130/225 V, three-wire, two-phase electric power discontinued systems called B1 are used to run old installations in small groups of houses when only two of the three-phase high-voltage conductors are used.

I know how to wikipedia too! They said usually, not "in some really rare cases"

To be clear the water cooling part is what I meant to be 'exotic'. 240V is pretty prevalent in datacenters or network closets when specced, but is rarely seen outside of large appliance installs in US homes and small offices.

Every home in the US with an electric stove or water heater is using 240v electricity. It isn't really very exotic. 3 phase power to homes IS very exotic though and I'm not sure why it would be useful in homes.

3 phase power is near universal inncentral and northern europe. And it's useful for powering saunas, electric warm water or bigger tools

why? The benefits of 3-phase power are really only used by factories with lots of large electric motors. 3 phase has no benefit for resistance heating.

You can move more power per conductor with three conductors than with two.

As a sidenote, my apartment has a 3x63A main fuse. Three-phase is everywhere here. Really convenient for ev charging too.

Delivering 100 amps over 240 volt is not an issue.

And welding .. nice when you have to use it.

In Norway, I understand that electric ranges are commonly cabled up with 3-phase wire that's about the size of a not-special extension cord here in the States. They accomplish this by using 400v.

Meanwhile, also here in the States: The wiring for my very normal (240v) electric range is the size of a baby's arm and might be even stiffer. (That last claim may be a bit hyperbolic: I've bent at least my share of 6/3 wire, but I don't think I've ever bent a baby's arm.)

The 400v is the important part. Not common at all in US homes but is very common in US factories.

Charging electric vehicles.

That would actually be 230V in most countries to be nitpicky. And the split-phase nature of 240V in the US (or 200V here in Japan) does make it somewhat more exotic. I guess building codes may be more expensive when you've got two hot wires?

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