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Comment by bityard | Hacker News Reader

The US grid (the last-mile bits anyway) isn't 110 volts, it's 220. It's just our houses that are wired for (mostly) 110 V.

Edit: I would love to see some sort of hybrid 110/220 V residential wiring/plug standard take hold in the US. It would require more expensive cable in the walls (since you need one additional conductor) and plugs, but it's totally doable. Most electrical products and appliances made these days are easily converted between 110/220, or run just fine on either.

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There is NEMA 14, which has hot,hot,neutral,ground, but I don't think anything lower than 20amps is available, and that's a locking one, 30 amps is available without locks, but 30 amps at 220v is a lot of power for household outlets. You'd need larger wire in the walls, not just more of them.

Any sort of outlet upgrade would need a really good plan for how to make it viable, because even if 100% of new construction used the new outlet, it would be decades before you could sell devices that relied on it.

You could include a second cable with the teapot, and wire it to work with 110 or 220 depending on which cable is used. This is already reasonably common. I have plenty of useless European cables laying around to prove it.

I have a 20A 220 circuit for an electric kettle with multiple 6-15Rs. It has a 20A gfci breaker.

> The US grid (the last-mile bits anyway) isn't 110 volts, it's 220. It's just our houses that are wired for (mostly) 110 V.

Similarly, in most of continental Europe phase-to-phase is 400V but most outlets are 230V. E.g. in my apartment only the stove has a 400V three-phase (4-wire) connection.

but 3phase (120degrees) is a lot better for powering motors than the 2 phase one in the US

3-phase is available in USA, but it's typically not provided to residences.

of course, the heavy motors/industrial equipment loves 3 phase AC. Higher voltages allow lower losses in the conductors, hence less copper needed everywhere incl. small motors as the current us lower through and through.

I kinda like that all but a couple outlets in my house can't kill me.

Also, I boil my water on an induction stove plugged into 50 amps at 220 volts. I'm not waiting around, to put it mildly.

30A at 400V is how we roll in the EU.

Wow. A typical induction hob in the UK is 32A at 230V. 230V is of course the nominal voltage of a single phase, although in practice in the UK the voltage is closer to 240V.

That's only 7.35kW of power. Do you have significantly more powerful cookers?

400V is only used for stoves or instant water heaters, but e.g. our stove uses 11kW actually.

If you don’t have these amounts of energy available, the temperature your instant water heater can reach or the speed with which you can cook obviously suffers (which I suspect is one of the reasons why americans prefer gas stoves so much).

the 3phase is used for motors - a lot more efficient (and the better power factor) than the single phase ones.

For industrial applications definitely, but at home there's few people who power motors with triphase or five phase power.

these are 3-phase stoves, they require a certified electrician to install, because they don't have plugs and there's no wall socket - just a place into which you can easily connect cables.

That makes sense. In the UK you can buy induction hobs that plug into sockets, but they are limited to a measly 3.7kW or there abouts. A nicer 32A induction hob needs hardwired (single phase).

You can have upgrade your domestic supply to three phrase, but AFAICT it's uncommon. Perhaps with electric cars and induction hobs replacing natural gas and petrol, it will become more common.

110v can easily kill you. It's a little harder to get a good solid connection through your body and into the ground than 220v. But it certainly can and does happen.

Amps kill, not volts. Hence high voltage low amp Tesla coil spark shows.

Thats not quite accurate- it is true that high amp current is deadly in many scenarios, but it takes both amps and volts to kill. High amp, high voltage current is a killer for sure, but high current at sufficiently tiny voltages is not necessarily deadly. Similarly, high voltage at low currents is usually not deadly (but can be very painful).

High voltage from a Tesla coil not only has low average current, but is subject to the skin effect. So while it can still cause a painful shock to your superficial sensory nerves, not much of that energy ends up in contact with the motor nerves.

TL,DR: you probably don't want to be shocked by a big Tesla coil, even though it won't kill you.

Your comment is completely irrelevant to wall sockets because they can all supply more than a tenth of an amp.

You need to be introduced to a classic: https://www.youtube.com/watch?v=XDf2nhfxVzg

Never heard of anyone getting killed by the 230V power in Europe. A few people I know touched it and it does hurt.

Perhaps it's because all houses have residual current devices which trigger much faster than fuses if current leaks to earth (eg through a person).

You could just run US-style appliance circuits to your kitchen, etc. Those are sometimes three conductor and other times four conductor.

However, I doubt it'd pass inspection if they were easily accessible from the counter-top.

If you're going to flout building codes anyway, it'd probably be easier/more practical to just run circuits with foreign outlets instead. Also, it might be easier to find appropriate GFCI breakers.

Use 6-15R or 6-20R. I think it would pass inspection because most safety requirements around gfci and afci don’t apply to 240V circuits

They do now, but only when accessible by a person. Even car charging station outlets do (even though every car charging station has gfci built in...)

Ah looks like this was a change in 2017. With any outlet there’s no guarantee what will end up plugged in so it’s logical to require it even if the purpose is an EV charger.

Thanks!

EU is on 50hz AC, where as the US is on 60hz. It would work fine for purely resistive appliances, and possibly devices with switching mode power supplies, but some devices would be unhappy plugging in to the wrong frequency at 220V.

I'm not sure about the phase alignment but that may be an issue as well. US is split phase, but Europe has 220 on a single conductor?

it's 230 (+-10%) nominal not 220. At my house it's around 235. It's 230v phase/live to neutral and 400V between live wires in 3phase. Nowadays 3-phase (120degree between each) is a commodity.

In my part of USA the typical voltage between the two sides of a breaker box is 240V. It actually moves around a bit below that value, but doesn't seem to ever exceed 240V. I think most consumer devices have the circuitry necessary to survive such variation, but I have seen some (expensive) professional equipment fried in an instant...

Thanks for that. Sounds wonderful compared to the typical 200 amp, split phase service we commonly have in the US.

How many non-switching power supplies will care either?

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