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Comment by pkulak | Hacker News Reader

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.

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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).

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.

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