3 ms·

As the sibling comment notes: The US/Canada are already split-phase 240v/120v systems. As near to 100% as makes no difference every single house is already wir

As the sibling comment notes: The US/Canada are already split-phase 240v/120v systems. As near to 100% as makes no difference every single house is already wired for 240v. In fact wired for it and using it: electric ranges, stoves, dryers, etc are all 240v. NEMA even defines 240v receptacles/plugs for normal amperage: NEMA 6-15 (two horizontal blades: meh face) and 6-20 (one vertical, one horizontal: wink with other eye closed). Unlike the common 240v dryer/large appliance cords that are huge and bulky 6-15 and 6-20 are about the same size as our current 120v plugs. They have the same compatibility as 5-15/5-20: The 15 amp version fits in the 20 amp receptacle but the 20 amp only fits 20 amp. And it is impossible to plug 120 into 240 or vice-versa. Everything made for 120v (to a rough approximation) is also rated for 240v. Unfortunately no one bothers to install the 6-15/6-20 plugs. There is nothing stopping any builder from doing it standard, especially in the kitchen. There is nothing stopping a homeowner/buyer from asking for it either. But no one does. Therefore there is no market for appliances that use these plugs. And thus no demand to wire for them. It would likely take a push from government, manufacturers, the NEC, etc to push for supporting 240v for common appliances. Start installing them in new homes. Offering the 240v version of electric kettles and such. Note: some European appliances can be wired up this way and will run fine because they tolerate 60Hz but not all of them.

zdragnar 1y ago
Eh, if we're going to be making big changes, might as well switch to the type C and type E plugs / sockets as well. They're safer, and the distinguishable nature from the type A / 120v devices currently in use (esp the ones that really can't handle 240).
- xenadu02 1y ago
  We already have plug standards here and they are good enough. Sure they're objectively worse but in practice the cases where it ever mattered are a rounding error. Better to encourage adoption of parts of our own existing standard then propose a wholesale change.
mauvehaus 1y ago
NEMA 6-15 and 6-20 seem to be pretty uncommon. This is no doubt in part because most stuff we run on 240 in the US is higher amperage anyway, and probably in part because some stuff also wants a neutral? The only NEMA 6 I have is on my table saw, and maybe the planer? Everything else is NEMA 14 (two hots, neutral, and ground). The upside of that is the bulb in your dryer, for example, can be a standard 120 volt bulb. I'd also like to note that the locking connectors plug and unplug a hell of a lot nicer than the non-locking ones, at least at the 30 amp size (which is common for a dryer). They just operate much more smoothly, presumably because they aren't relying on friction to keep them plugged in.
- xenadu02 1y ago
  > This is no doubt in part because most stuff we run on 240 in the US is higher amperage anyway, You've got the cause/effect backwards I think. The high amp stuff needs 240v to avoid ridiculous amp requirements. The lower power stuff just defaults to 120 because that's the most compatible leading to the chicken-and-egg problem. > probably in part because some stuff also wants a neutral? I've tried to come up with reasons this might matter but so far I can't. The Neutral (or really L2 in this scenario) is the reference plane. It moves in step with L1 and so when L2 is high (+120) L1 is low (-120), but from the POV of the reference that's just -240. Same for the other cycle half. In other words measuring voltage is relative in all cases. Unless you are measuring in relationship to the earth (an infinite sink for our purposes) you can't tell if you are seeing +120/-120 or +240/0. Perhaps there is something that relies directly on the voltage potential between Line and Ground, I just don't know of any. Most things that are sensitive to an actual ground reference are electronics which run on DC and are separated from the mains by their power supply anyway.
repiret 1y ago
> Unfortunately no one bothers to install the 6-15/6-20 plugs Almost no one, but I had a 6-15R put in my kitchen. Then I imported a 3kW tea kettle from the UK, lopped off the plug, and put on a 6-15P. And now my wife doesn’t have to wait very long for her hot water.

zdragnar 1y ago

Eh, if we're going to be making big changes, might as well switch to the type C and type E plugs / sockets as well. They're safer, and the distinguishable nature from the type A / 120v devices currently in use (esp the ones that really can't handle 240).

xenadu02 1y ago
We already have plug standards here and they are good enough. Sure they're objectively worse but in practice the cases where it ever mattered are a rounding error. Better to encourage adoption of parts of our own existing standard then propose a wholesale change.

mauvehaus 1y ago

NEMA 6-15 and 6-20 seem to be pretty uncommon. This is no doubt in part because most stuff we run on 240 in the US is higher amperage anyway, and probably in part because some stuff also wants a neutral? The only NEMA 6 I have is on my table saw, and maybe the planer? Everything else is NEMA 14 (two hots, neutral, and ground). The upside of that is the bulb in your dryer, for example, can be a standard 120 volt bulb. I'd also like to note that the locking connectors plug and unplug a hell of a lot nicer than the non-locking ones, at least at the 30 amp size (which is common for a dryer). They just operate much more smoothly, presumably because they aren't relying on friction to keep them plugged in.

xenadu02 1y ago
> This is no doubt in part because most stuff we run on 240 in the US is higher amperage anyway, You've got the cause/effect backwards I think. The high amp stuff needs 240v to avoid ridiculous amp requirements. The lower power stuff just defaults to 120 because that's the most compatible leading to the chicken-and-egg problem. > probably in part because some stuff also wants a neutral? I've tried to come up with reasons this might matter but so far I can't. The Neutral (or really L2 in this scenario) is the reference plane. It moves in step with L1 and so when L2 is high (+120) L1 is low (-120), but from the POV of the reference that's just -240. Same for the other cycle half. In other words measuring voltage is relative in all cases. Unless you are measuring in relationship to the earth (an infinite sink for our purposes) you can't tell if you are seeing +120/-120 or +240/0. Perhaps there is something that relies directly on the voltage potential between Line and Ground, I just don't know of any. Most things that are sensitive to an actual ground reference are electronics which run on DC and are separated from the mains by their power supply anyway.

repiret 1y ago

> Unfortunately no one bothers to install the 6-15/6-20 plugs Almost no one, but I had a 6-15R put in my kitchen. Then I imported a 3kW tea kettle from the UK, lopped off the plug, and put on a 6-15P. And now my wife doesn’t have to wait very long for her hot water.