5 ms·
At least in Sweden, all houses have a 3-phase, 400V supply. This is very different from the US which just supplies one phase to each house even if the supply it
by lutorm 6y ago
At least in Sweden, all houses have a 3-phase, 400V supply. This is very different from the US which just supplies one phase to each house even if the supply itself is 3-phase. This is why you commonly see 200+A main breakers on a house in the US whereas in Sweden, 25A is a pretty common main breaker size.
(It's as if the US grid characteristics were decided by the copper vendors... ;-)
- selectodude 6y ago>It's as if the US grid characteristics were decided by the copper vendors... It was designed without an issue with copper usage. Europe had very little development and quit a bit of rationing while building out the grid post-WW2. The US had no such issue and spent no time working within those constraints.
- nickff 6y agoWell, you have to consider that the USA (and Canada) were on the bleeding edge of technology when they adopted electrical grids. They were left with a... legacy, including the type-A plug and 110V single-phase power to residences. In your case, I believe each prong of your two-prong plug gets a different phase, so you have 3 possible pairs of phases to power each circuit from. This has the advantage of requiring smaller wires, but the disadvantage of increasing the risk if one is electrocuted.
- ghouse 6y ago> 110V single-phase power to residences. The US is 120V, or split-phase 240 V. Depending where you are, it's allowed to be ±5% at the meter. NEC guidelines say no more than 3% voltage drop from there.
- nickff 6y agoYeah, I got the number wrong, 120/220 always messes me up; will leave previous comment as-is so that yours makes sense.
- lucioperca 6y agoYou might have 208V and not 240V if you have two 120V phases 120 degree apart.
- nemetroid 6y agoNo, one prong gets a phase and one prong gets the neutral, resulting in 230 V. Only equipment designed for 400 V gets two (or three) phases.
- heftig 6y agoHouse-wide RCDs are also standard so if any current is not returned through neutral the circuit will be broken.
- gumby 6y ago> but the disadvantage of increasing the risk if one is electrocuted. Avoiding this was one of the design parameters of the "Schucho" plug design that is reasonably standard across Europe. You'll note the three prong plug has a longer ground that makes a connection before any hot one does. The US three prong is supposed to work that way too but the ground pin isn't long enough. I continue to be amazed how many devices still ship with only two prong plugs (everywhere: Europe, North America, Australia...) even if those prongs are polarized.
- kalleboo 6y ago> I continue to be amazed how many devices still ship with only two prong plugs (everywhere: Europe, North America, Australia...) even if those prongs are polarized Because most devices these days have plastic cases (Class II double insulated), so there's nothing metal to touch to get shocked even in the case of a fault. That coupled with how GFCI/RCDs are being widely adopted as well leads to grounding not being as important.
- kelnos 6y agoI'm (mostly) with you on the plastic casing, but in general (in the US at least) you only see GFCI in kitchens and bathrooms. Meanwhile I'm sitting 2 feet away from a nearly completely metal lamp with a two-prong plug.
- lucioperca 6y agoFind this very scary not having RCD on some plugs even with 120 Volts. Sure 240v with RCD will give you a massive shock but still will very unlikely kill you. No RCD on the other hand can be fatal on 120V: https://edition.cnn.com/2017/07/18/health/teen-bathtub-electrocuted-text-trnd/index.html https://edition.cnn.com/2017/07/18/health/teen-bathtub-elect...
- jhoechtl 6y agoIts Schuko, short for SCHutzKOntak, "contacts and ground".
- mcv 6y agoNot just Sweden. In Netherland, 3x25A is also pretty standard. To our surprise, our house turned out to have 1x35A, so when we got a big induction cooker, we had to upgrade to 3x35A.