I've been reading through old posts about people wanting to use European kettles and other appliances on a 240v US circuit. Forget the 50hz/60hz frequency difference for resistive loads and universal power supplies, and any legal/code issues -- I'm speaking purely from a safety and lab/testing scenario, are there really any grounding issues with the L1/L2 to ground voltage being 120v rather than an EU 230v L/N arrangement?

First, it should be no issue for any 2 pin Euro plug devices that are ungrounded since no ground is involved. Even if it was something like a Schuko plug with ground, Schuko plugs are unpolarized so the plug could be inserted in either direction, mixing up line & neutral, so neutral and ground couldn't be bonded in the appliance.

Second, I'm struggling to understand how it would be any different then grounding a US 240v appliance such as an EVSE with a NEMA 6-50 outlet -- any failure from either L1 or L2 to ground will result in 120v potential.

I could only see using an EU 230v appliance being a problem on a US 240v circuit if the neutral were bonded to the ground somewhere in the appliance. I've tested many appliances in the US and EU and have never come across one that measures any continuity between the appliance case and neutral. Further, wouldn't this arrangement trip a GFCI or RCD unexpectedly?

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    \$\begingroup\$ For appliances like a toaster with a metal housing where do you think the metal housing is connected up in a EU toaster? (I don't really know. I'm asking.) Do they leave the metal housing to float and then unconnected to either N or L? That would not be safe should a failure inside the unit cause an L-wire to touch the housing. So I think the housing will be tied to N. But if you now make N = L1 in the US, doesn't that mean the metal housing is now hot in the US? You do seem to be saying your experience is that the metal case is left floating. So I'm asking, not telling. \$\endgroup\$ Nov 8, 2023 at 0:34
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    \$\begingroup\$ @periblepsis EU plugs are unpolarized as far as I know so not possible to hook anything to only neutral. It's 50/50 if it gets live or neutral. I guess these devices always use a ground or else a fault could be very bad. \$\endgroup\$ Nov 8, 2023 at 1:01
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    \$\begingroup\$ if you find an appliance that has PE bonded to one of its live mains terminals, don't use it either in US or EU. \$\endgroup\$
    – tobalt
    Nov 8, 2023 at 1:54
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    \$\begingroup\$ @opencir I'll give this Q a +1 because now I'm curious. First, curious because there are so many different governing authorities in the EU and I'm interested in an education about their commonalities and vagaries. Second, because you've made me curious just generally about the situation with appliances with metal surfaces like toasters in the EU. I'm sure the authorities are just as concerned about safety and fire hazards as they are in Canada and the US, if not more so. But I'm mostly ignorant about it. \$\endgroup\$ Nov 8, 2023 at 2:00
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    \$\begingroup\$ I'm really confused what all this fuzz in the comments is about. Quite obviously metal cases are connected to PE. (If not doubly insulated and thus not necessary to protect) what else should they be connected to? Can't be phase, that would be fatal, can't be neutral, since no way to tell from phase. And even with such a way, what would be the point in having PE if we're not using it as protective earth? \$\endgroup\$ Nov 8, 2023 at 2:30


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