Personally I would just wire some NEMA 240V outlet and then have a separate adapter with a pigtail of that receptacle type and a workbox with the UK receptacle. It's a little unwieldy, but it puts the questionable hackery outside the realm of the building inspection at least.
Whether it's actually safe I though, that I am curious. Obviously the kettle can get the 240V potential it expects, but the neutral is center tapped out of the split phase transformer, right? Not sure how people wire this. (Doesn't the neutral wind up having to be one of the hots instead?)
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 different zero reference point. The neutral from the wall would be unused, and the ground would be wired as usual.
I'll think this through thoroughly though, I was definitely glossing over those details, so thank you!
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 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!
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. :)
> Most UK kettles are not 3000W, and most of the ones that are, are junk. Y
They may not be 3 kW, but even the most basic of them are 2200W [0], and 3000W ones are readily available are not much more expensive [1]. They're also not really junk - they're a lump of plastic, a hot plate and a thermistor - the difference between a £8 one and a £80 one is almost all aesthetics.
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.
Whether it's actually safe I though, that I am curious. Obviously the kettle can get the 240V potential it expects, but the neutral is center tapped out of the split phase transformer, right? Not sure how people wire this. (Doesn't the neutral wind up having to be one of the hots instead?)