5 ms·

It's probably the most remarkable difference. It's interesting how houses are wired for 10-20A of current everywhere, regardless of voltage. You'd assume that s

It's probably the most remarkable difference. It's interesting how houses are wired for 10-20A of current everywhere, regardless of voltage. You'd assume that since European houses are mostly wired for 16A then US houses would be wired for 32A (or the other way around, if you know US houses wired for 15A, you would assume the European wires for 8A). But curiously that's not the case. Ignoring the UK with their 13A/30A rings for a moment, since their wiring is unique.

eutectic 3y ago
Resistive losses are related to current (I^2 R), so you need thicker wires to deliver the same power at a lower voltage. I guess it was decided that it wasn't worth the expense.
- wongarsu 3y ago
  Sure, obviously. But you'd expect power requirements to be more or less the same, and the ideal wire diameter to be dependent on voltage. But instead what happened is that the wire diameter is more or less constant, and Europe just uses more powerful electrical devices.
  - rootusrootus 3y ago
    > Europe just uses more powerful electrical devices Aside from kettles? I guess maybe some people have electric heaters? What else pulls enough power that the extra voltage will matter? Vacuums maybe, but no, those are limited to 1600W.
    - wongarsu 3y ago
      Just looking up my local (German) retailer: - Irons are commonly 2000-3200W (3200W is 14.5A at 220V) - Portable Induction Stovetops are 3000W - Deep Fryers are 2000-3000W - Hair Dryers are 2000-2500W And of course some things are connected via 3-phase 400V (3 220V phases, because of the 120° phase offset that's 400V between any two phases) - actual oven + stovetop combinations, about 7000W for the stovetop, plus 1000W for the oven - many tankless water heaters, 5000W-24000W seems common The most impactful in day-to-day use are probably kettles and hair dryers, but with stovetops and water heaters there's probably a big difference in the prevalence in gas vs electrical, and tankless vs boiler simply due to wiring.
      - rootusrootus 3y ago
        That's a good list, thanks. I'd be interested to know what the experience is like between a 120V hair dryer and a 240V model. I don't have enough hair to worry about such things, but my wife does, and it seems like her hair dryer gets hot enough that she usually turns it down a bit anyway. The 'industrial' level appliances are probably less of an issue, because the wiring run is limited and you can customize it however you need to. I could go down and buy a 36kW electric tankless water heater today and wire it up without any difficulty. Though it would probably be worth upgrading my 200A panel in that case. Ranges sound like they're probably pretty similar. Typical modern electric ranges in the US are about 10kW. Three phases would be handy for reducing the cost of wiring, though. Cost me $1500 USD just for the wire when I ran four new circuits last year. Couple of them were 50A, which is partly why it was so expensive, but mostly it's just that copper is $$$. Any bigger than 60A and I'd switch to aluminum.
        wongarsu 3y ago
        I don't have first-hand experience with the difference in hair dryers either, but I imagine it's mostly air velocity? With more power you can turn more air scalding hot, meaning you can offer higher fan speeds without compromising temperature.
        fragmede 3y ago
        Also consider: your wife might not be the kind of woman who would use one on high. Pain tolerances among women, like men, vary.
rspoerri 3y ago
If you increase Ampere you must increase the width of the cable, or it will overheat. If you increase Voltage you must increase the insulation around the cable.
rootusrootus 3y ago
32A capable wiring is much more expensive. And if we are being honest, the number of modern appliances that need more than 1800W is very small outside of the kitchen. If it were a common problem people would be installing 6-20 receptacles, but that's pretty rare. I have exactly one, and it's in the garage.
sbradford26 3y ago
Largely this is resolved by US houses having a lot more circuits. My bathroom has a dedicated 20 amp (2.4 kW) circuit for the outlets and a separate 15 amp (1.8 kW) circuit for the lights. Every bedroom in my house has its own 15 amp breaker. The kitchen has 3 20 amp breakers for different wall outlets, a 15 amp breaker for the lights, then a 30 amp 240v (7.2 kW) breaker for the cooktop, and a 20 amp 240v (4.8 kW) breaker for the oven. For the a typical US house the standard feed into the house is 200 amps at 240v. So 48kW of power coming in we just segment it down a lot more.
- bialpio 3y ago
  It starts to become annoying when you have a home office for 2 people though. 2 PCs + 4 monitors and some random things in a room can start approaching the wattage limit. Especially given that I think it's not too common to have one circuit per room (anecdata: my house has one circuit for all outlets per story; not counting bathroom and kitchen which I believe are mandated by building code to be separate).
  - hajile 3y ago
    Lots of smaller (kw) circuits is safer than a few very large circuits. The NEC in the US actually stipulates that you must use different receptacle styles for higher ampacities specifically because it is less dangerous. If you run a small appliance on a 30-40amp circuit, you run the risk of that seemingly safe appliance pulling the full 40+ amps required to trip the breaker
    - bialpio 3y ago
      Not sure if I understand - can you clarify? Did you mean that a normally safe 1.5kW appliance runs the risk of cooking itself if it's connected to a 40amp circuit? If yes, then sure, that makes sense. > Lots of smaller (kw) circuits is safer than a few very large circuits. Not fully convinced about the safety aspect but it definitely feels more convenient (can selectively turn rooms off if you need to work on something) - if I'm ever opening the walls, I'm going to switch to that approach. At the very least, I want to have a dedicated 20amp circuit in the home office...

eutectic 3y ago

Resistive losses are related to current (I^2 R), so you need thicker wires to deliver the same power at a lower voltage. I guess it was decided that it wasn't worth the expense.

wongarsu 3y ago
Sure, obviously. But you'd expect power requirements to be more or less the same, and the ideal wire diameter to be dependent on voltage. But instead what happened is that the wire diameter is more or less constant, and Europe just uses more powerful electrical devices.
- rootusrootus 3y ago
  > Europe just uses more powerful electrical devices Aside from kettles? I guess maybe some people have electric heaters? What else pulls enough power that the extra voltage will matter? Vacuums maybe, but no, those are limited to 1600W.
  - wongarsu 3y ago
    Just looking up my local (German) retailer: - Irons are commonly 2000-3200W (3200W is 14.5A at 220V) - Portable Induction Stovetops are 3000W - Deep Fryers are 2000-3000W - Hair Dryers are 2000-2500W And of course some things are connected via 3-phase 400V (3 220V phases, because of the 120° phase offset that's 400V between any two phases) - actual oven + stovetop combinations, about 7000W for the stovetop, plus 1000W for the oven - many tankless water heaters, 5000W-24000W seems common The most impactful in day-to-day use are probably kettles and hair dryers, but with stovetops and water heaters there's probably a big difference in the prevalence in gas vs electrical, and tankless vs boiler simply due to wiring.
    - rootusrootus 3y ago
      That's a good list, thanks. I'd be interested to know what the experience is like between a 120V hair dryer and a 240V model. I don't have enough hair to worry about such things, but my wife does, and it seems like her hair dryer gets hot enough that she usually turns it down a bit anyway. The 'industrial' level appliances are probably less of an issue, because the wiring run is limited and you can customize it however you need to. I could go down and buy a 36kW electric tankless water heater today and wire it up without any difficulty. Though it would probably be worth upgrading my 200A panel in that case. Ranges sound like they're probably pretty similar. Typical modern electric ranges in the US are about 10kW. Three phases would be handy for reducing the cost of wiring, though. Cost me $1500 USD just for the wire when I ran four new circuits last year. Couple of them were 50A, which is partly why it was so expensive, but mostly it's just that copper is $$$. Any bigger than 60A and I'd switch to aluminum.
      - wongarsu 3y ago
        I don't have first-hand experience with the difference in hair dryers either, but I imagine it's mostly air velocity? With more power you can turn more air scalding hot, meaning you can offer higher fan speeds without compromising temperature.
      - fragmede 3y ago
        Also consider: your wife might not be the kind of woman who would use one on high. Pain tolerances among women, like men, vary.

rspoerri 3y ago

If you increase Ampere you must increase the width of the cable, or it will overheat. If you increase Voltage you must increase the insulation around the cable.

rootusrootus 3y ago

32A capable wiring is much more expensive. And if we are being honest, the number of modern appliances that need more than 1800W is very small outside of the kitchen. If it were a common problem people would be installing 6-20 receptacles, but that's pretty rare. I have exactly one, and it's in the garage.

sbradford26 3y ago

Largely this is resolved by US houses having a lot more circuits. My bathroom has a dedicated 20 amp (2.4 kW) circuit for the outlets and a separate 15 amp (1.8 kW) circuit for the lights. Every bedroom in my house has its own 15 amp breaker. The kitchen has 3 20 amp breakers for different wall outlets, a 15 amp breaker for the lights, then a 30 amp 240v (7.2 kW) breaker for the cooktop, and a 20 amp 240v (4.8 kW) breaker for the oven. For the a typical US house the standard feed into the house is 200 amps at 240v. So 48kW of power coming in we just segment it down a lot more.

bialpio 3y ago
It starts to become annoying when you have a home office for 2 people though. 2 PCs + 4 monitors and some random things in a room can start approaching the wattage limit. Especially given that I think it's not too common to have one circuit per room (anecdata: my house has one circuit for all outlets per story; not counting bathroom and kitchen which I believe are mandated by building code to be separate).
- hajile 3y ago
  Lots of smaller (kw) circuits is safer than a few very large circuits. The NEC in the US actually stipulates that you must use different receptacle styles for higher ampacities specifically because it is less dangerous. If you run a small appliance on a 30-40amp circuit, you run the risk of that seemingly safe appliance pulling the full 40+ amps required to trip the breaker
  - bialpio 3y ago
    Not sure if I understand - can you clarify? Did you mean that a normally safe 1.5kW appliance runs the risk of cooking itself if it's connected to a 40amp circuit? If yes, then sure, that makes sense. > Lots of smaller (kw) circuits is safer than a few very large circuits. Not fully convinced about the safety aspect but it definitely feels more convenient (can selectively turn rooms off if you need to work on something) - if I'm ever opening the walls, I'm going to switch to that approach. At the very least, I want to have a dedicated 20amp circuit in the home office...