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My car charger can boil water really fast [video]

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Re: My car charger can boil water really fast [video]

#61

Post by quesera »

jchw wrote: post #60
quesera wrote: post #56

Earlier quoted context omitted.

Hmm, yeah! I hadn't thought much about the differences between UK and US 240VAC service. In the US, it's 240V 60Hz, split-phase with center-tapped neutral, and an independent ground wire. In the UK, it's 240V 50Hz, single-phase with independent neutral and ground. Frequency difference should be within design tolerance. and if my EE memory serves, the phase difference should be acceptable -- just measured from a diffe…

Basically my concern is, ordinarily the potential from neutral to ground would be roughly 0V with some slack. In this case, though, the potential from neutral to ground would necessarily be 120V. I have no idea what the implications of that may be, but it seems important.

I think it works if the US neutral is left unused (terminated in the electrical box).

E.g, something like this:

  (US proposed)    (UK kettle)     (UK standard)
  (2-phase)      ┌─────────────┐   (1-phase)
                 │             │
  L1 120V 0° ────┼─ Hot(240V) ─┼── Hot 240V 1ph
                 │             │
  Neutral ───X   │             │
                 │             │
  L2 120V 180° ──┼─ Neutral ───┼── Neutral
                 │             │
                 │             │
  GND ───────────┼─ GND ───────┼── GND
                 │             │
                 └─────────────┘
I think this is right, but I'm not 100%. The kettle should get what it needs, but I'm less certain whether a GFCI or ArcFCI breaker would have opinions that must be accounted for. I'll check with someone more qualified than myself to be sure!

Re: My car charger can boil water really fast [video]

#62

Post by jchw »

quesera wrote: post #61
jchw wrote: post #60

Earlier quoted context omitted.

Basically my concern is, ordinarily the potential from neutral to ground would be roughly 0V with some slack. In this case, though, the potential from neutral to ground would necessarily be 120V. I have no idea what the implications of that may be, but it seems important.

I think it works if the US neutral is left unused (terminated in the electrical box). E.g, something like this: (US proposed) (UK kettle) (UK standard) (2-phase) ┌─────────────┐ (1-phase) │ │ L1 120V 0° ────┼─ Hot(240V) ─┼── Hot 240V 1ph │ │ Neutral ───X │ │ │ │ L2 120V 180° ──┼─ Neutral ───┼── Neutral │ │ │ │ GND ───────────┼─ GND ───────┼── GND │ │ └─────────────┘ I think this is right, but I'm not 100%. The kettle…

Yes I understand. But what I'm saying is, normally neutral and ground would have roughly 0V potential, but in this case the UK neutral and UK ground will have 120V potential between them, because the US 120V second phase will have 120V potential to ground. (It bears noting that I am just a random guy and not any kind of expert. No formal education or credentials relating to electricity whatsoever.)

Re: My car charger can boil water really fast [video]

#63

Post by quesera »

jchw wrote: post #62
quesera wrote: post #61

Earlier quoted context omitted.

I think it works if the US neutral is left unused (terminated in the electrical box). E.g, something like this: (US proposed) (UK kettle) (UK standard) (2-phase) ┌─────────────┐ (1-phase) │ │ L1 120V 0° ────┼─ Hot(240V) ─┼── Hot 240V 1ph │ │ Neutral ───X │ │ │ │ L2 120V 180° ──┼─ Neutral ───┼── Neutral │ │ │ │ GND ───────────┼─ GND ───────┼── GND │ │ └─────────────┘ I think this is right, but I'm not 100%. The kettle…

Yes I understand. But what I'm saying is, normally neutral and ground would have roughly 0V potential, but in this case the UK neutral and UK ground will have 120V potential between them, because the US 120V second phase will have 120V potential to ground. (It bears noting that I am just a random guy and not any kind of expert. No formal education or credentials relating to electricity whatsoever.)

I think you're thinking about it on the kettle side, and I was thinking on the breaker side.

I think the kettle side would not care. It may be a ground fault in UK wires, but the kettle has no reason to detect it, and nothing sensitive enough inside to care. If I'm wrong, I'd expect to know shortly after starting the very first use. :)

Re: My car charger can boil water really fast [video]

#64

Post by js2 »

quesera wrote: post #63
jchw wrote: post #62

Earlier quoted context omitted.

Yes I understand. But what I'm saying is, normally neutral and ground would have roughly 0V potential, but in this case the UK neutral and UK ground will have 120V potential between them, because the US 120V second phase will have 120V potential to ground. (It bears noting that I am just a random guy and not any kind of expert. No formal education or credentials relating to electricity whatsoever.)

I think you're thinking about it on the kettle side, and I was thinking on the breaker side. I think the kettle side would not care. It may be a ground fault in UK wires, but the kettle has no reason to detect it, and nothing sensitive enough inside to care. If I'm wrong, I'd expect to know shortly after starting the very first use. :)

You guys know he talks about this 4 minutes into the video, right?

See also: https://diy.stackexchange.com/a/315031

Re: My car charger can boil water really fast [video]

#65

Post by quesera »

js2 wrote: post #64
quesera wrote: post #63

Earlier quoted context omitted.

I think you're thinking about it on the kettle side, and I was thinking on the breaker side. I think the kettle side would not care. It may be a ground fault in UK wires, but the kettle has no reason to detect it, and nothing sensitive enough inside to care. If I'm wrong, I'd expect to know shortly after starting the very first use. :)

You guys know he talks about this 4 minutes into the video, right? See also: https://diy.stackexchange.com/a/315031

Err, well, from the title, I expected it to be a garage experimentation video without practical information. Thanks for the correction. :)

Video was published last week and reaches the same conclusions as this thread. Timely, and reassuring! Thanks for the SE link too.

Re: My car charger can boil water really fast [video]

#66

Post by crote »

emchammer wrote: post #43
crote wrote: post #31

Earlier quoted context omitted.

Sure, but over in 230V-land 3500W hot plates are completely standard, and can plug into any regular wall socket. Same with microwaves and hot-air ovens: just put it anywhere on your kitchen countertop and plug it into the nearest socket. We do also have a "kitchen plug" for high-powered appliances. Those go up to 7.3kW in their regular dual-single-phase 16A version, 11kW when wired with three phases (quite common in…

What is the specific standard for domestic 16 A and 25 A 3-phase plugs you’re referring to?

Perilex.

Re: My car charger can boil water really fast [video]

#67

Post by crote »

jchw wrote: post #60
quesera wrote: post #56

Earlier quoted context omitted.

Hmm, yeah! I hadn't thought much about the differences between UK and US 240VAC service. In the US, it's 240V 60Hz, split-phase with center-tapped neutral, and an independent ground wire. In the UK, it's 240V 50Hz, single-phase with independent neutral and ground. Frequency difference should be within design tolerance. and if my EE memory serves, the phase difference should be acceptable -- just measured from a diffe…

Basically my concern is, ordinarily the potential from neutral to ground would be roughly 0V with some slack. In this case, though, the potential from neutral to ground would necessarily be 120V. I have no idea what the implications of that may be, but it seems important.

Go for a German kettle instead of a British one. Schuko wall plugs are reversible, so there will be no assumptions about neutral vs. ground.

Both live and neutral wires have to be treated as if they were both live, because 50% of the time they'll be swapped around.

Re: My car charger can boil water really fast [video]

#68

Post by jchw »

js2 wrote: post #64
quesera wrote: post #63

Earlier quoted context omitted.

I think you're thinking about it on the kettle side, and I was thinking on the breaker side. I think the kettle side would not care. It may be a ground fault in UK wires, but the kettle has no reason to detect it, and nothing sensitive enough inside to care. If I'm wrong, I'd expect to know shortly after starting the very first use. :)

You guys know he talks about this 4 minutes into the video, right? See also: https://diy.stackexchange.com/a/315031

I watched the video already before this HN thread, being a Technology Connections subscriber, but I genuinely forgot or missed that it discussed that aspect. I'm not surprised, though.

Re: My car charger can boil water really fast [video]

#69

Post by herbst »

Mistletoe wrote: post #40
throw0101c wrote: post #9

He mentions induction 'hot plates' towards the end, and says that they're limited to the same 1800W and 120V as kettles, but there are "commercial" portable induction stoves that are 220V and can go up to 3500 and 5000W; e.g.: * https://www.vevor.ca/induction-cooktop-c_10592/vevor-portabl... * https://www.trueinduction.com/Commercial-Single-Induction-Co... Just need a NEMA 6 plug (GFCI/AFCI per code as well probably)…

I swear Vevor makes everything.

It's a Chinese reseller, with some quality control maybe but surely some great service attached to it. But you'll find 90% without vevor Logo on AliExpress.

Still big fan and regular customer, very surprised to see they have a .ca too and likely more.

Re: My car charger can boil water really fast [video]

#70

Post by juliangmp »

maccard wrote: post #39
jchw wrote: post #11

Earlier quoted context omitted.

This begs the question, and I've genuinely thought this before, of why we don't just strap a battery to a kettle and end this silly debate. If it takes 5 minutes to boil a cup of water in a 1000 watt kettle, that's somewhere around 80Wh... I guess it would be kind of expensive, but couldn't you make a pretty fast kettle with some number of high discharge battery cells? (Well honestly, I guess the real answer is outsi…

That seems a terrible waste of batteries to me. A boiling water tap seems like a better idea to me - electric heater with a pressurised insulated vessel that just dispenses from your tap.

I've seen those around, even with an integrated carbonator to get sparkling water right from the tap. They're neat but also ridiculously expensive
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