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> Really all residential connections in the US are 220V split phase Really all modern residential connections in Europe are 400V three phase electric power, c
by jhoechtl 3y ago
> Really all residential connections in the US are 220V split phase
Really all modern residential connections in Europe are 400V three phase electric power, capable to immediately power an electric motor without the need of capacitors.
No matter how you put it, the US residential power grid is conceptionally lagging.
- dghlsakjg 3y agoYou do realize that the grid runs at a completely different voltage than what is actually delivered to standard residential service, right? It is entirely possible to get three phase, high-voltage power in North America, it just isn't run to individual houses unless specifically requested.
- kukkamario 3y ago400V three phase is wired to all houses at least here in Finland. All 3 phases are wired to the electric box and then that splits phases to normal sockets and for lighting etc. Ovens use three phases and detached houses usually have separate 3-phase plugs outside for running eg. heavy construction tools, like cement mixer and such. Oh right and sauna stove also needs all 3 phases obviously. Even apartments have that full 3-phases, but just for plugging in the oven and the sauna stove.
- chris_va 3y agoThere really isn't a huge advantage for 3 phase unless you are doing high-power DC rectification or trying to run a motor. The US grid is basically 3-phase everywhere, but it's neither needed nor cost-effective to run it into the home. Now, the 400V part is different. That would require less copper (but with a safety cost).
- pangolinja 3y ago[flagged]
- chris_va 3y ago... the infrastructure is high voltage 3-phase, same as EU. Also, stone tools are easier to replace :P
- mulmen 3y agoInventor syndrome. Same thing with our cell phone networks and space ships. When you invent something you end up with the most “archaic” version, by definition. But it seems to still be working. American pragmatism says there’s better places to allocate resources.
- deleted 3y ago[deleted]
- deaddodo 3y ago[flagged]
- pavlov 3y agoThe Nazi genocide in the East was explicitly modeled on the treatment of Native Americans in the 19th century. So, like voltage, it’s another case where Americans invented something and Europeans doubled down.
- catchnear4321 3y agoyes, but who invented the americans
- hot_gril 3y agoInteresting thing I learned, horses actually originated in the Americas. Some of them migrated to Asia, then the ones in the Americas died out before human civilization, so only the Old World civs had them. When Europeans brought horses to the Americas, they were bringing them back.
- 3y ago
- kukkamario 3y agoCurrently probably biggest advantage is electric car charging. It is easy and cheap to add high power fast charger when there is already 3 phases available. 400V between phases so 230V per phase. Safety is provided by making plugs not expose contacts while half plugged. US plugs are really unsafe compared to plugs used in most of the Europe.
- hinkley 3y agoThe last transformer between houses and the grid is 440v three phase. As I understand it the distribution networks all look pretty much the same, it’s only the last mile that differs. And thus consumer electronics. If you want to run a machine shop, it’s a pain but not impossible to get 440 three phase wired straight through to your business. But consumer “heavy” motors and induction stoves run on two phase 230V.
- saiya-jin 3y agoIts everywhere in Europe. I haven't seen nor heard about say a single oven not plugged into 400V. I've lived in 4 different countries in east & west, all the same. Even when traveling around a bit, I see those special plugs in convenient places, where you may expect to plug something powerful for some heavier work. Anything high power, you go for this plug. I'd imagine car charging would also benefit from this but not personally in that market yet.
- pmontra 3y agoThis HN thread is the first time I learned about 400 V to homes in Europe. My oven is 220 V. I just checked the manual. All my house is 220 V. I live in Italy. Plugs are usually Shuko for high power appliances (washing machine) and two smaller pins for low power (phone chargers.) By the way, Italy traditionally had a three pin in a line high power plug but more and more appliances are coming with Shuko plugs so wall socket are either bi-standard or just Shuko now.
- jaywee 3y agoThe 400V is between phases. 230V is between a phase and ground. Ie, you get 3 wires (phases) of 230V from the 400V connection. Btw, Europe standardized at 230/400V in the nineties. In Czechia we switched from 220V to 230V in 1993. Not sure when Italy did, but probably around the same time.
- chipsa 3y ago"Standardized". The allowable voltage for power is normally something like 6%. When they switched from the mis-mash of 220 and 240V to 230V, they specified the allowable voltage range was wide enough to encompass both of those, including the allowable voltage range for 240V. So largely it was just "Everything is 230V now, and try to make sure new stuff is actually 230V".
- tomatocracy 3y agoYes. “Standardising” to 230V +/-10%, allows for 220/230/240V +/-6% (the previous standards used in different countries) to all coexist without actually changing any equipment.
- kelnos 3y ago> detached houses usually have separate 3-phase plugs outside for running eg. heavy construction tools, like cement mixer and such. Is this sort of use common in Finland? It seems like kinda a waste of money and materials to install the infrastructure to allow everyone to run heavy construction equipment off their home's electrical supply.
- malermeister 3y agoI can't talk about Finland, but in Central Europe it's pretty common as there is a culture of house building. In the US, a developer typically buys an entire neighborhood's worth of land and builds a bunch of houses there to sell to individuals. Over here, the individuals will typically buy their own small plot of land and then have a house built there according to their specifications. You need to be able to run heavy construction equipment to do so.
- djhn 3y agoHow esle is the home going to get renovation work and upkeep done?
- Gravityloss 3y agoSince you need three phase 380V for the sauna and the kitchen anyway, and probably for the ground or air heat pump too... it doesn't cost almost anything to run a cable from the electrical box and installing a three phase socket. This shows a 32A 400V socket costs under 10 euros: https://www.taloon.com/voimapistorasia-pinta-bals-101-3pne-32a-400v-ip44 https://www.taloon.com/voimapistorasia-pinta-bals-101-3pne-3...
- Ekaros 3y agoIt is more efficient. Going from 4 wires to 5 is not a big deal if you then can have triple power. Or you can use thinner wires thus less material overall. The split phase is two lives, neutral and ground. 3-phase is 3 lives, neutral and ground.
- RedShift1 3y agoIn Europe the wiring in the ground is always 3 phase, they just connect only 1 phase. You can upgrade to 3 phase for a fee and then a guy comes and switches it over. They don't need to open up the streets or anything like that to get you 3 phase power.
- justincormack 3y agoNot always - I live in the countryside in the UK and we seem to have single phase sadly.
- youngtaff 3y agoTends we live in a row of cottages and the phase is split between us so every third house is on the same phase Pretty sure that’s standard for the UK
- Wildgoose 3y agoIt is. I remember when we had a power cut and when I went outside I could see that only a single phase had been lost - every third house had gone dark, the rest remaining lit. I reported it and it was sorted pretty quickly.
- gambiting 3y agoNearly everywhere in UK has only a single phase supply, it's how the grid in this country is designed.
- Symbiote 3y agoHouses in the UK are connected to a single phase, but a three phase supply is available if it's needed — the cable is in the street, though digging a new trench to connect to it is often costly. Larger users are presumably connected with three phases by default — that primary school in the middle of the housing estate, the retirement home that has several lifts, not-tiny shops, the small block of flats etc.
- Blackthorn 3y agoYou can request it all you want in North America, but you probably won't get it. A three phase converter is way more likely.
- mcpackieh 3y agoYou can get it if you're willing to pay for it, but you may not like the quoted price.
- Blackthorn 3y agoHaha, I can't get it at all here. It's not a matter of paying an absurd price that will get you a PhasePerfect for 10% of it. It's a matter of it just not being available at all.
- bluGill 3y agoHave you really asked? Generally it is possible if you pay, but expect to pay $100,000+ to get it. Most neighborhoods don't have the right wires to you pay paying for all new poles and wires to your neighborhood. That said, a few cities/states don't allow 3 phase to residences in their building code. However most do allow it, and so it is just a matter of convincing the power company to run it.
- bob1029 3y agoIf I had a periodic need for three phase power on-site, I would just purchase (or rent) a generator that can provide this style of output.
- mcpackieh 3y agoI think most home shops use phase converters, either rotary phase converters or variable frequency drives. With those you can create a third phase to run machines that need it, although obviously you won't have as much power available to you.
- cptcobalt 3y agoIn the US, the amount of three phase electricians that will work at a Residential home and not charge you an arm and a leg for it is vanishingly low, almost certainly not worth it.
- mitthrowaway2 3y agoThat's sort of a chicken-and-egg problem. If residential three-phase electricity were commonplace, electricians would all happily handle it at their standard rates, your air conditioners and refrigerators would all be running on it.
- MichaelZuo 3y agoNo? It clearly takes more training and has more liability since the consequences of a mistake are more serious. The average billable rate would inevitably be higher regardless.
- jrockway 3y agoWhat kinds of mistakes are harmless at 120V @ 100A vs 400V @ 30A?
- rootusrootus 3y agoTouching 120V with dry skin is nearly always harmless. 240V is considerably more exciting.
- Blackthorn 3y agoMaybe it's a little different for just a converter, but mine didn't have a problem installing a Phase Perfect and running a few three-phase outlets for it.
- b3orn 3y agoWait, there are special electricians for three-phase in the US, is this like an additional certification or are the normal ones scared of three phases?
- sokoloff 3y agoFar more common for 3-phase motor loads in residential areas (already an unusual requirement) is the point use of a rotary phase convertor or (more commonly now) variable frequency drive to run the 3-phase motor from the existing split-phase supply.
- Kirby64 3y agoHow many residential appliances benefit from three phase, and is the benefit outweighed by the additional cost of more copper for the additional wires? For example, a common big motor that needs a starter capacitor is a HVAC unit. Usually the copper to run those is extremely expensive, on the order of hundreds of dollars. Adding an additional wire may add an additional hundred dollars or more. By comparison, starter caps are quite cheap. $20 for a HVAC sized one. That also isn't counting any of the costs of three phase infrastructure for breakers etc. That also isn't even counting that many appliances are moving to inverter based technologies that don't utilize induction motors at all, such as induction hobs. Or, many appliances with no benefit from extra phases (resistive heating devices such as ovens, dryers, toasters, etc). Seems to me that the tradeoff is worth it.
- loandbehold 3y agoTransmitting same amount of power at higher voltage requires LESS copper.
- deleted 3y ago[deleted]
- kelnos 3y agoBut you need an extra conductor, no? Doesn't that make up for the reduced amount of copper in each one?
- nullc 3y agoFor three phase vs single face, the amount of copper doesn't go up since the current is shared across the additional conductors-- generally the amount of copper required is actually lower due to power factor improvements. However, for low capacity hops the cost of additional insulation and extra copper needed to achieve ampacity (for worst case fault currents-- the cable must have higher capacity than the breaker so the breaker trips first and with 3ph you have three over-provisioned conductors instead of two) may make it worse off.
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- quickthrowman 3y agoHere are the motor loads for a typical residence: -1/2 to 3/4 HP furnace fan - 3 to 5 ton AC unit Neither of these benefit from a 3-phase motor aside from not having to swap out $10 start/run capacitors, the conductors would be #8 for 3p and #6 for split phase. You can easily power a three-phase motor on a split-phase service with a VFD. You can get three-phase power in certain locations at a residence, but you pay a monthly connection charge and commercial rates.
- nvy 3y agoWhy are AC units measured in weight?
- kens 3y agoIt's actually an interesting unit: a ton of air conditioning is equal to the cooling that you get from melting a ton of ice per day. It has nothing to do with the weight of the air conditioner. Presumably this was useful in the olden days when businesses used ice for cooling and wanted to know what size of refrigeration unit they would need. One ton of cooling is defined as 12,000 BTU/hour. The "real" value is 11966; apparently it's coincidental that it is so close to a round number. (One ton of refrigeration is 3517 watts in metric.)
- sokoloff 3y agoI thought the conversion was exact. The latent heat of fusion of 1 pound of water at 0°C is 144 BTU. 144 BTU/lb * 2000 lb/ton / 24 hr is 12000 BTU/hr per ton exactly.
- kens 3y agoNo, the latent heat of fusion is 143.6 BTU/pound, not 144. It's just a coincidence that the energy to raise water one °F ÷ the energy to melt ice is almost 144.
- nvy 3y agoGood grief what an obtuse system of units.
- lol768 3y ago> Really all modern residential connections in Europe are 400V three phase electric power Not the case in the UK.
- kelnos 3y agoThe answers and comments on [0] would seem to suggest that's not true. Seems the power grid has the capability of delivering three phase power, but many (most?) homes in quite a few European countries don't actually have all three phases delivered. > No matter how you put it, the US residential power grid is conceptionally lagging. That's only the case if you believe the US is "missing out" on all that much with our split-phase setup. I don't think that's the case, really. Even for EV charging, using the 240V across the -120V and 120V lines is more or less fine. We've been doing the same thing with our electric stoves, water heaters, etc. for quite some time now. Certainly there are some things you can do with 3-phase that aren't really feasible with split-phase, but I don't think most people living in the US care too much. It's true that those who do are probably upset about it, though! Also consider that the US power system is trivially 3-phase! We just don't wire all those phases to homes, as we a) don't generally see the need to, b) chicken-and-egg problem suggests that most people wouldn't be able to use it anyway, since appliances made for the US wouldn't be able to take advantage of it. [0] https://electronics.stackexchange.com/questions/625353/is-3-phase-power-in-any-way-better-than-split-phase-power-in-a-residential-setti https://electronics.stackexchange.com/questions/625353/is-3-...
- microtonal 3y agoWe definitely had the wires for three phases coming into the house (Europe, NL) when we got a heat pump and induction cooking plate, the electricity company connected two additional phases in our utilities closet. I asked them, and the only thing they did was actually hooking it up. It was also free (there was a small cost, but the government subsidizes it to encourage that people switch to heat pumps).
- lazide 3y agoLong haul power transmission is almost always 3 phase AC in the US - it can be done using either 3 or 4 wires. It tends to better distribute loads and requires smaller conductors for the same power transmission level. Split phase is almost always the last mile to residential customers as it’s simpler and easier to reason about (less likely to have severely unbalanced phases too) and requires fewer conductors.
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- hajile 3y ago400v 3-phase in a house is crazy to me. I was hit with 480v once (someone cut my lockout and turned the power on). That stuff will outright kill you unless someone else is around to help. One of my favorite things about US residential power is that 120v is far less dangerous when homeowners (or worse, kids) accidentally do something they shouldn't.
- atonse 3y agoI read it as 400v coming into the house, not coming out of outlets... Like 220v is coming into the house in the US.
- deleted 3y ago[deleted]
- ohgodplsno 3y agoYou forget to take something crucial into account: the US's safety standards are laughable when it comes to electricity. The standard US plug is _begging_ for people to stuff things in it like say, knives, rarely if ever has an earth pin, has no shutters, is massively unsafe, the cable gauge is laughable, GFCI outlets are a miracle to find, and the building rules are... let's just say they're an invitation for house fires. Most european houses have a single 400v outlet: right in your kitchen, for the oven (which means the oven is going to be right in front of it.) The likelihood of a child playing with it is close to nil. As for adults, the vast majority of people are taught to just flip the breaker and work on it if needed. I promise you more people died of sticking metal into US outlets than from 400 volts.
- lazide 3y agoEU countries have their own history of terrible plugs and outlets, not that far back either. The 2 pin continental plug (when not shuttered, which old outlets aren’t) has all the same issues as the old US two prong plug - but twice the voltage! Modern US outlets are usually shuttered, and 3 prong grounded outlets have been the required standard since about 1969. Which is over 50 years ago.
- gumby 3y ago> No matter how you put it, the US residential power grid is conceptionally lagging. Not just conceptually == reliability is lower than that of its peers: https://www.statista.com/statistics/268155/ranking-of-the-20-countries-with-the-highest-quality-of-electricity-supply/ https://www.statista.com/statistics/268155/ranking-of-the-20... (if you don't have a statista account, US is at the bottom of this list at 98.6) State level data: https://www.eia.gov/electricity/data/eia861/ https://www.eia.gov/electricity/data/eia861/
- IcyWindows 3y agoI don't believe any country can have 100% reliability, so the data is suspect.
- gambiting 3y agoUK is in Europe and yet this isn't true here. Nearly all residential properties in this country are wired for single phase 220V. It's true on the continent though.
- chartpath 3y agoUK scored a massive own goal and are no longer part of Europe ;)
- gambiting 3y agoI assume that's tongue in cheek, but EU and Europe are two different entities - UK is still very much in Europe.
- KptMarchewa 3y agoIt never was. It's an island, while Europe is a continent.
- timc3 3y agoEurope is composed of several islands as well as the continent.
- rlpb 3y agoBy that logic Switzerland isn't in Europe either :)
- earthboundkid 3y agoIf Switzerland were in Europe then Germany would have marched through to get to France. They didn't therefore etc QED.
- sammorrowdrums 3y agoGood induction cookers and electric car chargers, heat pumps and things really do often require the high voltage for best function so this high voltage three-phase is also becoming standard for the energy transition. I had to upgrade my electricity meter and switch box (even though as mentioned three-phase to the house is already standard) recently in order to accommodate planned environmental upgrades.
- webmobdev 3y agoThree-phase power supply for residential use is common even in India.