[HN Gopher] Why does the USA use 110V and UK use 230-240V? (2014)
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Why does the USA use 110V and UK use 230-240V? (2014)
Author : dilawar
Score : 159 points
Date : 2023-08-29 09:48 UTC (13 hours ago)
(HTM) web link (electronics.stackexchange.com)
(TXT) w3m dump (electronics.stackexchange.com)
| mhandley wrote:
| As a Brit, the best thing about 230v is being able to run a 3kW
| kettle to make my tea. I took this for granted until I moved to
| the US.
| kccqzy wrote:
| It's possible to ask an electrician to install a 240V outlet in
| the US and then get a UK-spec kettle. You just need to make
| sure the kettle doesn't care about the frequency difference
| (probably not), and the hot-hot vs hot-neutral difference (also
| probably not).
| bluGill wrote:
| Possible, but the outlet will have a different plug. Most
| window air conditioners use that type of outlet, and some
| garages will have it for hobby equipment. I don't think you
| can legally install a UK (or EU) outlet in the US even though
| everything that plugs into it would be just fine on our 240V
| power (a few clocks won't work right, but they won't be
| harmed or harm anything)
| Kirby64 wrote:
| Presumably, you would chop off the plug on the UK/EU
| kettle, and replace it with your own NEMA 6-20 plug. No
| need to install a UK/EU plug in your house. Also works good
| in case you need to use some sort of weird industrial
| equipment that needs 240V.
| teamonkey wrote:
| Or just use a travel adapter
| TrueGeek wrote:
| The difference really is night and day between a US and UK
| kettle.
|
| The worst part of the British system though (although I don't
| think this has anything to do with voltage, IDK) is there is
| nowhere to plug-in your razor, hair clippers, hair dryer,
| toothbrush, curling iron, etc. etc.
| pmlnr wrote:
| That's building regulations, sadly. Sockets need to be
| multiple meters from splash zones, but there's an exception
| for shaver sockets, which have their own transformer, limited
| amps, and have a plug that looks very similar to the non-
| grounded EU plugs.
| tialaramex wrote:
| Yeah, both bathrooms in my (UK) home have such sockets, I
| don't actually use them, the electric toothbrush gets
| charged by this desk instead, but they exist.
|
| Regulations change over time, this home's bathrooms are all
| interior, with fans to evacuate moisture, and the toilets
| accordingly have internal overflow+, both these features
| were not legal when my parents home was built.
|
| + Historically for a residential toilet in the UK if the
| water rises above the intended maximum level in the tank,
| it just runs into a pipe to the outside of the building, in
| principle you can now see what's wrong and it's not
| dangerous... but, if you don't fix it promptly this results
| in a stain on the building exterior, as well as potentially
| wider water damage, plus it can freeze in mid-winter which
| isn't good. But wait, a toilet has a very obvious place to
| dump unwanted water, it's connected to the sewer and if
| _that_ is broken you 've got much more serious problems. So
| a modern toilet tank just re-uses the flush mechanism to
| dump excess water the same place as everything else. This
| elegant solution, already needed in some commercial
| applications, was I believe made legal in newer residential
| building regulations maybe in the 1980s.
| allendoerfer wrote:
| Thank you, now I have even more highly specific but
| useless information about British homes. It will sit next
| to my knowledge about why you guys (used to) have two
| faucets.
| Symbiote wrote:
| They still mostly choose to have two taps in the
| bathroom.
|
| Part of the reason I emigrated.
| rdsnsca wrote:
| You don't use GFCI's in the UK?
|
| https://www.canadianhomeinspection.com/home-reference-
| librar...
| blue_cookeh wrote:
| Yes - though we call them RCDs and they're typically
| located in the consumer unit. Up until recently they'd be
| shared across several circuits (a "split" or "dual" RCD
| consumer unit). Nowadays regs are pushing for each
| cicruit in the consumer unit to be protected individually
| by their own RCBO (almost the same thing as an RCD/GFCI)
| bemusedthrow75 wrote:
| No, we can still do that -- I have a dual-voltage shaver
| point next to my bathroom sink with my electric toothbrush
| plugged in.
|
| There's a famous, common 20VA fixture by Legrand with a
| distinctive symbol. I asked an electrician about this last
| year. Most electricians will still fit them.
|
| It won't supply a hairdryer or a pair of curling tongs,
| probably. Not that you really want such things in a bathroom
| or without an earth pin.
| TrueGeek wrote:
| Yeah, it's fine for me as all my stuff is rechargeable and
| cordless anyway. But my wife needs her hairdryer. In the US
| any plugs that could get wet are GFCI [1] so you just wait
| for it to dry out and then push the reset button.
|
| I've rarely had it happen in the bathroom, even with
| outlets right next to a sink. But I had an outlet at ground
| level outdoors that would trip during heavy storms
| sometimes. We fixed it by putting a physical cover over it.
|
| 1: https://en.wikipedia.org/wiki/Residual-current_device
| bemusedthrow75 wrote:
| Yes. New houses and rented properties in the UK have to
| have an RCD now as well. But we have the additional EU
| building codes.
| [deleted]
| the_mitsuhiko wrote:
| With induction stoves getting more popular that's less of an
| issue nowadays.
| swarnie wrote:
| Still, putting the stove on to make a cup of tea seems wrong.
| ikekkdcjkfke wrote:
| Nobody heard of Quooker?
| ThatMedicIsASpy wrote:
| yeah but it is 5 times faster than a kettle
| the_mitsuhiko wrote:
| That seems purely emotional. An induction stove heats
| faster than a kettle at almost the same efficiency.
| Tuna-Fish wrote:
| No, it really does not. A typical induction stove has
| ~2kW of power on each element, and is ~20% less efficient
| at heating water than the resistive kettle.
|
| This makes it about half as fast at boiling water.
| oblio wrote:
| You made me check and adjust my other comment:
|
| https://www.aeg.co.uk/kitchen/cooking/hobs/induction-
| hob/ikb...
|
| 3.7kW for the main element.
|
| Also, why would it be less efficient? Due to the
| distance?
| Tuna-Fish wrote:
| Note that the 3.7kW element can only provide all that to
| a single vessel if it covers the entire area of the
| element.
|
| The resistive element submerged in the water dumps very
| nearly 100% of energy into the water. The stove heating
| the kettle has many more sources of loss, but mostly that
| it first heats a piece of metal, which is not fully
| submerged in water.
| the_mitsuhiko wrote:
| In theory, in practice the induction heating on a regular
| pan is faster than my kettle by almost three times. YMMV
| on type of kettle and induction hob used. But it
| generally means that if you live in the US and you have
| an induction hob, there is absolutely no reason to buy a
| kettle.
| rightbyte wrote:
| You might want to decalcify your kettle.
|
| Edit: Wait. Are you using a frying pan to heat tee water
| to make it faster?
| the_mitsuhiko wrote:
| My experience with US induction stoves is limited but I
| believe it can also deliver 3.5kW on boost. My induction
| stove boosts to 3.8kW for heating which beats my kettle
| significantly. I also measures the efficiency and it's
| quite comparable.
| Tuna-Fish wrote:
| What is the power of your kettle?
| the_mitsuhiko wrote:
| 2200 Watts.
| londons_explore wrote:
| A British kettle on 230 volts boils enough water for a
| cup of tea in about 45 seconds. (3 kilowatt heater, 300
| ml of water, theoretically takes 33 seconds, but slightly
| longer because it has to heat the body of the kettle too)
| bloopernova wrote:
| I wonder if it's possible to replicate that circuit in a
| USA house but still stay within code. I'd love to make my
| tea faster!
| dboreham wrote:
| Pretty much. My office building was formerly a
| woodworking shop and has wiring for 220V. Long ago I
| bought a laser printer on eBay. The seller omitted to
| mention it was a 220/240V model (probably why it was
| cheap). Laser printers unlike most appliances are not
| dual voltage because the fuser is run directly off the ac
| supply line. So I wired in a 6-20 outlet and changed the
| plug. Worked fine for many years. I also have a table saw
| running from a 6-20 outlet. There is a 6-15 NEMA type
| that presumably would provide a UK compatible supply. I
| think the problem might be how to provide in-wall cabling
| that's to code for 220V. In my case I already had conduit
| with THHN wire.
|
| Not necessarily to code, consult your electrical engineer
| and lawyer before doing your own wiring, etc.
| rootusrootus wrote:
| > I think the problem might be how to provide in-wall
| cabling that's to code for 220V
|
| That's no problem, standard romex nm-b is rated up to
| 600V. The only real difficulty in doing that in most US
| homes is that it's all or nothing. You'd have to upgrade
| all receptacles on the circuit to 240V. Depending on when
| your home was built, the kitchen might well have several
| circuits for the wall receptacles (even just one circuit
| per receptacle, not terribly uncommon in my area), which
| makes converting one of the circuits to 240V pretty
| trivial.
|
| Given how many appliances these days use switching power
| supplies capable of a wide range of voltage, I wouldn't
| be totally surprised if it was possible to wire an entire
| house with nothing but 6-15 or 6-20 receptacles and not
| have too much difficulty sourcing compatible appliances.
| londons_explore wrote:
| Most _kitchen_ appliances require the right voltage. They
| normally have a heater or motor driven direct from the AC
| voltage.
|
| Most devices you'd use outside the kitchen usually will
| work on any voltage - with notable exceptions being
| vacuum cleaners, washing machines and fan heaters.
| rootusrootus wrote:
| For sure you'd want to be careful. My Kitchenaid stand
| mixer would certainly be unhappy if it were plugged into
| a 240V outlet, but Kitchenaid makes a 240V version that I
| could replace it with. A lot of work, but technically
| doable.
|
| Probably about as likely as wiring up DC receptacles
| throughout the house. Zero.
| bluGill wrote:
| I believe that US code requires a dedicated circuit for
| all 240v outlets. Only 120V outlets can be chained. The
| only people who use 240v outlets are planing on using all
| the power it can provide, if they want a second outlet
| they want a second circuit as well.
|
| Check with your local codes of course. Even if the local
| codes allow it, your building inspector may not.
| mindslight wrote:
| 12-2 NM/Romex is fine for 240V (120V+120V), and is
| commonly used for things like large ACs, heaters, etc.
| Mark the white wire with red electrical tape at both ends
| (or really any color besides white/grey/green, but avoid
| black because while technically correct it just blends in
| as regular electrical tape).
| TheSpiceIsLife wrote:
| I use a Panasonic flatbed microwave to heat precisely the
| volume of water I want by filling the tea cup(s) I want.
|
| Two minutes on high (1100 watt microwave output from,
| IIRC 1800 watt input) per cup. So usually two minutes for
| the one cup of I intend to drink.
|
| Every electric kettle I've ever owned has a minimum
| volume of at least two cups. Who bother heating two cups
| if I'm only going to drink one at a time.
|
| Tasmania (AU), 240v / 100amp supply to residential is
| standard.
| londons_explore wrote:
| Any kettle with a flat bottom (no exposed heating
| element) can be used with far less water than the 'min'
| line - and some models don't have a min line at all.
|
| All new kettles have boil-dry protection as well, so they
| won't be damaged with no water at all.
| londons_explore wrote:
| Install an A/C socket in your kitchen. Then buy a British
| 240 volt 3 kilowatt kettle from eBay and wire on a US A/C
| plug (NEMA 6-15) - hooking the brown and blue wires from
| the kettle to the two line pins, and the green/yellow
| wire to ground.
|
| This would be both code legal, safe and functional.
|
| It would also be possible to use a clothes dryer socket
| (NEMA 14-30), but you should install a smaller than usual
| breaker for the circuit (15 amps), since the british
| kettle normally has a 13 amp fuse in it's plug, but a
| NEMA plug does not contain that.
| bloopernova wrote:
| Sweet, I had no idea it would be that straightforward.
| Thank you for the information!
| zoomablemind wrote:
| I wonder how does this compare to boiling water in a
| regular coffee mug in microwave oven?
| CalRobert wrote:
| To be honest for the many years I lacked a proper stovetop
| kettle it felt wrong to not have the whistle. Though I also
| missed the auto-shutoff.
| googlryas wrote:
| Huh? That's how people did it for all of eternity until
| about 75 years ago.
| bemusedthrow75 wrote:
| We drink an unbelievable amount of tea. Firing up the hob
| each time would be silly, when you can fill a kettle to
| the minimum and have boiling water in an incredibly short
| time. Not much more than half a minute with a good modern
| kettle.
| rootusrootus wrote:
| That sounds like a good use case for an insta-hot tap. No
| filing anything, always ready to go.
| wil421 wrote:
| Isn't that the traditional method with a kettle that
| whistles?
| mhandley wrote:
| We have an induction stove too and it's great. But the kettle
| is still significantly faster at boiling water.
| oblio wrote:
| I'm kind of surprised by this. An induction stove turns the
| entire kettle into a resistive element so water boils super
| quickly.
|
| At least with EU induction stoves, so 230V.
| rootusrootus wrote:
| > At least with EU induction stoves, so 230V.
|
| US induction cooktops/stoves are almost always 240V,
| unless you get a little countertop burner.
|
| > I'm kind of surprised by this.
|
| As am I. The first time I put a small pot of water on my
| induction cooktop and turned it on maximum power, I
| laughed out loud. If I'm only doing enough for a cup of
| coffee or tea, it starts boiling so fast you don't want
| to step away.
| [deleted]
| mhandley wrote:
| Ours is a Smeg model. The two large rings are 2.3kW, with
| a outer booster ring to 3kW. The problem is if I'm just
| boiling water for my tea with a saucepan, only the inner
| ring is triggered. I can put a large pan on there and get
| 3kW to match the 3kW kettle, but then I've got to warm a
| large metal pan too, whereas the kettle has very little
| thermal mass and is lightweight and easy to fill too.
| Tuna-Fish wrote:
| An induction stove is still really inefficient at heating
| water, compared to an electric kettle with the resistive
| element in the water and 3kW of power.
| the_mitsuhiko wrote:
| There is a small difference but not much. I compared my
| 230V Kettle with my 400V induction stove and it's within 5%
| or so. Obviously it depends a bit on what pot you use. I'm
| guessing most losses come from the lack of insulation on
| the metal pot.
| oblio wrote:
| Why? I'm not sure I understand the logic.
|
| For example this: https://www.emag.ro/plita-cu-inductie-
| aeg-hob-hood-60-cm-ikb... (in the EU), at max power can
| supposedly reach 7.3kW.
|
| Edit: Checked per element, max 3.7k, more than enough
| anyway.
| vel0city wrote:
| For the induction cooktop, there's circuitry to drive the
| induction system, which then creates magnetic fields,
| which then interacts with the metal pot, which gets hot
| and heats the water on one side while radiating heat into
| the air on the other. There's a lot of stages for losses
| here.
|
| On an electric kettle, there's just a heating element,
| often directly bathed in the hot water.
|
| There's absolutely less losses with the electric kettle,
| so for a 3kW kettle and a 3kW induction cooktop the
| kettle is _slightly_ more efficient. _Slightly_.
| beeforpork wrote:
| Hmm, I measured it once (temp increase over time, computed
| back into watts, compared to a watt meter on the induction
| cooker), and I found that of the 3,5kW I put in, 80%
| actually convert to temperature increase in the water. That
| is not too bad, is it? Are electric kettles more efficient?
| andersa wrote:
| They should make turbo kettles that hook up to 3 phase
| power like a stove. That seems like it would be fun. Why
| stop at 3kW, when you can have 11?
| doublesocket wrote:
| My in-laws have fried three different induction hobs boiling
| a kettle on them. Good quality brands too, they just can't
| seem to cope with frequently being set to max.
| myrmidon wrote:
| Are people actually using induction stoves for tea, though?
|
| For me, a big selling point of the kettle is that you don't
| have to clean it and stow it after every use, so I would
| still use the kettle even if it was slower (maybe no longer
| for pasta or when cooking in general though)...
|
| edit: I guess you could just get a teapot that is induction-
| compatible, didn't think of that.
| PrimeMcFly wrote:
| You don't really have to clean a pot either if you just
| used it to boil water.
| fireflash38 wrote:
| Mostly just descaling, but cleaning it with soap and
| water isn't going to do much about that - you need an
| acid like vinegar or citric acid.
| bowsamic wrote:
| There's no chance I'm bothering with getting out a stovetop
| kettle every time I want a tea. Far easier to just have a
| separate kettle
| teamonkey wrote:
| You don't put the kettle away, it lives on the stove!
| CalRobert wrote:
| If you use an induction hob, a classic stovetop kettle (the
| kind that whistles!) will allow you to boil water quickly. The
| large ring on my last hob was 3kw.
| iso1631 wrote:
| How 1950s!
| CalRobert wrote:
| I'm not in my seventies but I do have fond memories of the
| kettle whistling as a kid.
| xavdid wrote:
| TIL about the word "hob". Americans call it a "cooktop" or
| "stovetop" or "range"
| rootusrootus wrote:
| Nitpick: a cooktop is just the burners, a range is an
| appliance with burners and an oven. It's relatively common
| on newer houses to separate them. E.g. I have a 36 inch
| induction cooktop and a completely separate double wall
| oven in another area of the kitchen.
|
| AFAIK stovetop is also sometimes used when people mean
| cooktop, though in my area it's more often a casual
| reference to the burners of a range. I'm sure that
| convention varies wildly across the country.
| CalRobert wrote:
| I always just called it the stove.
| lol768 wrote:
| I still find it very odd they call the central heating
| boiler/heat pump a "furnace".
|
| A furnace is what you use to make clay set into a pot!
| sib wrote:
| "Kiln"?
| [deleted]
| BaseballPhysics wrote:
| Not worth it. A temperature controllable kettle that shuts
| itself off and can keep water warm is both incredibly
| convenient and far more safe.
| shawabawa3 wrote:
| lots of new induction hobs have "boil detection" and auto
| shut off, fwiw
| BaseballPhysics wrote:
| So I just need to upgrade my current induction stove to a
| newer model? That seems reasonable... ;)
| rootusrootus wrote:
| I have a temperature controllable "kettle" (tank) under my
| sink connected to a tap and I get water at 195F. I agree on
| the convenience. They are pretty common.
| CalRobert wrote:
| But no whistle! Good point on safety though
| zeroonetwothree wrote:
| Now that I have a 5kw induction cooktop I can boil water
| incredibly fast. However I'm not sure it's that useful since
| it's not like I'm standing there watching it, so whether it's 1
| min or 5 min doesn't matter.
| laurencerowe wrote:
| I definitely notice the difference in speed between a Uk and
| US kettle.
|
| In the UK I put the water on then while it's boiling get a
| mug and tea bag and then the kettle is boiled very soon
| after.
|
| In the US I generally wonder off as the kettle takes a couple
| of minutes longer.
| secondcoming wrote:
| Sometimes you need an emergency cup of tea
| fragmede wrote:
| If it took 15 seconds, you'd stand there and watch it.
| bluGill wrote:
| I have a really old infrared range that takes 20+ minutes to
| boil a pot of water. Believe me when it takes that long it
| does matter. (it is on the list to replace, but there are
| higher priorities in this house to fix first, and only
| limited budget)
| 1vuio0pswjnm7 wrote:
| Those electric kettles in the US boil water _really slow_ when
| one is used to 230v.
| vehemenz wrote:
| As an American, I find the boiling speed of 1L in an electric
| kettle to be remarkably fast compared to drip coffee or
| boiling on the stove. Granted, that says more about my
| expectations than the actual speed.
|
| Generally I use an insulated 4L kettle that stays warm all
| day, so it heats up very quickly when needed and somewhat
| negates the issue.
| ianburrell wrote:
| I find with electric kettle that I use the right amount of
| water since there are markings for volume. It also heats up
| to the right temp for coffee instead of to boiling. Both
| mean that electric kettle is faster than on stove. I like
| that it will maintain right temp for the second pour for
| coffee.
| amelius wrote:
| From the article:
|
| > USA uses 230-240 VAC, too. The only difference is that we
| ground it in the center, creating "split" phases, reducing the
| peak voltage relative to ground and making it easier to
| interface low-power loads. But high-power loads (stoves, water
| heaters, clothes dryers, etc.) operate across the full voltage,
| reducing the current required.
| greggsy wrote:
| The power companies know this, and time their cutovers from
| Europe with the end of Eastendets, which is when people turn on
| their kettle for a cup of tea before making dinner. (I'm not
| sure if that's still a good hint, but it certainly was ten or
| so years ago.)
| seanw444 wrote:
| Tom Scott's video on this is interesting, as a side note.
| nickt wrote:
| Guy Martin did a good 3 part TV show earlier in the year
|
| https://www.channel4.com/programmes/guy-martins-great-
| britis...
| nickt wrote:
| It's called "TV pickup", and Wikipedia has a good article
| explaining it, especially the bit about using pumped storage
| to meet demand in seconds.
|
| https://en.wikipedia.org/wiki/TV_pickup
| iso1631 wrote:
| Less important now. Back when 17 million would tune in to
| watch Coronation Street 3 times a week it was a much bigger
| thing. It's rare to get half that for legacy live TV
| outside of specific major broadcasts (The Euro 2020 final
| pulled in 30 million) -- the 10th most watched show of 2022
| only got 8 million and the soaps are lucky to get 6 -
| inlcuding those watching time-shifted.
| rootusrootus wrote:
| As an American, I have a faucet at my kitchen sink that will
| give me water at 195F. That takes care of nearly all my needs
| for truly hot water. When I do need the last few degrees to get
| a roiling boil, my induction cooktop has a 3700W burner that
| will do it in a hurry.
| sib wrote:
| We have the same. The system has a high-end water filter
| which then exits into a split, one outlet of which goes to a
| room-temp tap and the other into the heater, so we have both
| filtered "cold" and hot water.
| wffurr wrote:
| That sounds really dangerous. My hot water is set to 120degF.
| oaktowner wrote:
| We put one in 15 years ago and use it every single day.
| Sorry for the commercial link, but
| https://insinkerator.emerson.com/en-us/insinkerator-
| products... is an example. It's great to have near-boiling
| water on demand.
| rootusrootus wrote:
| It's just one tap at that sink, clearly identified, in
| addition to the regular hot & cold water taps. I don't run
| my main hot water tank at 195F, that would be dumb.
| hughes wrote:
| So you have an auxiliary heater at the tap? How is energy
| delivered to this system?
| rootusrootus wrote:
| Yep, I have a separate tap at the kitchen sink which is
| connected to a small (about 3 liters IIRC) tank
| underneath. I have it set to 195F, though it can be set
| as high as 210F. There is a receptacle in the cupboard
| under the sink where it plugs in.
| LUmBULtERA wrote:
| I'm curious, do you know how many kwh that uses in a day?
| throw0101b wrote:
| > _As an American, I have a faucet at my kitchen sink that
| will give me water at 195F._
|
| The building code for the province of Ontario (Canada) states
| that delivered water cannot be higher than 49C (120F);
| SS7.6.5.1. Maximum Temperature of Hot Water:
|
| * https://www.ontario.ca/laws/regulation/r04023
|
| An exception is given for dish-- and clothes washer outlets.
| buildsjets wrote:
| No. The law you quoted limits the maximum temperature of
| hot water supplied by fittings to fixtures.
|
| It says nothing about fixtures that increase the
| temperature of water and dispense it, and does not limit
| the temperature of dispensed water. Instant hot taps are
| both legal and commonplace in Canada.
|
| https://ca.zipwater.com/
| nullc wrote:
| Best appliance I've ever owned.
| hot_gril wrote:
| 195@ tap water coming from a dedicated tank is not a common
| American thing, in case someone is wondering.
| tiborsaas wrote:
| How many accidental burn injuries you or your guests have?
| rootusrootus wrote:
| Zero. The 195F tap is not the same one you use for normal
| hot & cold water. The normal hot water in our house is set
| to 140F (we do not have any small children or elderly, if
| we did I might dial it down to 120F).
| pimlottc wrote:
| To be clear, in the US the "instant hot" tap (when present)
| is separate from the main adjustable-temperature faucet.
| It's normally off to the side and visually distinct. It's
| usually much smaller and provides a limited amount of water
| from a pre-heated tank under the sink.
| kccqzy wrote:
| And yet people have 36kW water heaters and they can't boil the
| water!
|
| https://www.homedepot.com/p/Rheem-Performance-36-kw-Self-Mod...
|
| /s
| wongarsu wrote:
| 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 wrote:
| 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 wrote:
| 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 wrote:
| > 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 wrote:
| 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 120deg 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 wrote:
| 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 wrote:
| 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 wrote:
| 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 wrote:
| 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.
| sbradford26 wrote:
| 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 wrote:
| 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 wrote:
| 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
| Symbiote wrote:
| Britain solves this with fuses inside appliance plugs.
|
| The continental European system doesn't really solve it,
| as far as I know, so you have thicker wires on low power
| appliances than you would in the USA.
| sbradford26 wrote:
| The US also has fused plugs but their are not widely used
| for some reason. I see them mostly on Christmas lights,
| but I have also seen it on some small home electronics
| like a window fan and air purifier.
| bialpio wrote:
| 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...
| sbradford26 wrote:
| Largely yes a 1.5 kW device (a 12.5 amp space heater for
| example) is less safe on a 40 amp circuit. Since if it
| fail pulling more load than designed but not truly
| shorted the breaker may not trip. But if you put that
| space heater on a 15 amp circuit it would most likely
| trip the breaker. As other commenters have said the UK
| addresses that risk with fuses in the plug.
|
| Also I recently redid my kitchen and I added an
| additional 20 amp circuit just for the kitchen island
| outlets and it has been super nice.
| bialpio wrote:
| Are safety concerns alleviated here by GFCI breakers? In
| what cases could this appliance pull more amps than it
| was designed for? I know it's not required for circuits
| outside kitchen and bathroom, but I was thinking about
| just replacing all the breakers with combined GFCI/AFCI
| ones (especially given that my circuits are so old that
| there's no ground on them, in which case code I believe
| mandates that the outlets are GFCI-protected and labeled
| as "no ground").
| sbradford26 wrote:
| So the risk would be reduced. Since if the failure causes
| a electricity to travel anywhere other than the neutral
| it will cause the gfci to trip. A scenario where a device
| would pull more power would be a short developing in a
| heating element reducing its resistance. So it would just
| pull more power but all of the power is still going to
| the neutral and wouldn't trip the GFCI.
|
| Also with replacing all your breakers it can increase
| safety. But first the breakers are not cheap. Second it
| can lead to a lot of nuisance trips, albeit that is
| better than it used to be with modern breakers.
| bialpio wrote:
| Gotcha, so I guess it'll only protect from electrical
| hazard but fire hazard is still going to be there...
|
| Breakers are probably going to be a bit cheaper and
| easier than opening all the walls to redo the circuits
| though...
| sbradford26 wrote:
| Yeah your AFCI in theory is supposed to help reduce fire
| risk. Since failures like that cause arcing. But yeah it
| will be around $60-$80 per breaker, but there is
| definitely cheaper than ripping open walls to re-run
| wires.
| sbradford26 wrote:
| Yeah sadly having separate circuits for each room is not
| required by the NEC to the best of my knowledge (and
| might be overkill depending on the situation). Usually
| though best practice is to have a separate circuit though
| for each bedroom. Depending on how your outlets are wired
| it might be possible to split them off onto separate
| breakers relatively easily though.
| rootusrootus wrote:
| 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.
| sph wrote:
| I'm struggling to understand how the British grid works, as an
| Italian transplated to UK. IIRC in Italy most residential
| circuit breakers have a limit of 3.3 kW, so it's pretty easy to
| trip it with a few appliances running, and we don't even use
| electric kettles that much.
|
| Yet in Britain, with a 3 kW kettle, I've never managed to trip
| it, with a combination of laundry machine, electric oven,
| microwave, dishwasher. Is there no circuit breaker limit?
| laurencerowe wrote:
| That sounds almost as bad as what we have to deal with in the
| US!
|
| I live in an early 20th century apartment in San Francisco
| and I quickly learned not to run my 1.8kW kettle at the same
| time as my 1.2kW microwave as it would consistently trip the
| power.
|
| More annoying is when the fridge compressor motor starts up
| while running either as that also trips the power.
| unethical_ban wrote:
| I just moved from a place where, if I ground my beans and
| then turned on the kettle or toaster, I could hear the
| motor slow down.
| rickboyce wrote:
| If you want a deep dive this video made by a British
| electrician is worth a watch https://youtu.be/hZN6hiGLtrE
|
| In a perfect world a ring circuit is a clever invention - it
| offers a circuit that can safely deliver about 7.3kW with
| hardly any more copper than normally could deliver about
| 4.6kW.
|
| However in practice they have a hidden failure mode - if you
| break the ring they will carry on working apparently without
| problem except it's quite possible that you now have
| overheating cables in a wall somewhere. In the real world
| houses are full of changes (both DIY and professional) that
| inadvertently break the ring and it's not at all uncommon to
| see in a house with even modest refurb works having been
| done.
| MisterTea wrote:
| Going from memory but this is an artifact of WW2. There was a
| copper shortage so they decided to save on wiring costs by
| running only a few high current circuits through the whole
| house. The appliance plugs are instead fused as any fault in
| the appliance would happen after the plug. This is why UK
| plugs are all fused - they are the final branch circuit over
| current protection device. I actually like the idea.
| jonatron wrote:
| We have ring circuits, which are typically on 32A breakers.
| iso1631 wrote:
| And it's great, until the ring is broken. If a ring becomes
| disconnected, you then have a single 4mm circuit rated at
| 18A carrying 30A.
| sph wrote:
| 3000 W / 230 V = ~13A, does this mean I could run two 3kW
| kettles and still have 1.3kW spare before everything shuts
| down?
|
| That's massive.
| sbuk wrote:
| When when the UK was rebuilding the housing stock post WW2,
| ring mains (or circuits) were designed to both increase
| consumer safety and to combat the anticipated post-war copper
| shortage. This design allows for high integrity earthing and
| greater power per unit of floor area for a given cable size
| than a radial circuit. Most white goods (Dishwashers, washing
| machines, etc.) are locally fused and often ovens are on a
| separate ring with their own fuses in the distribution board.
| This is why you rarely trip the circuit. It can be done
| though.
| dotancohen wrote:
| > I'm struggling to understand how the British grid works
|
| Like most things, understanding the history helps. The ring
| circuit was designed because it uses less copper than other
| methods - and copper was scarce after WWII. Almost all other
| design decisions either come directly from the idea of saving
| copper, or the idea that there are not enough Legos to step
| on so the electric plug must substitute.
| dfawcus wrote:
| Post WW2 for newly built small flats, ring mains were
| designed to save on copper (as it was in shortage). The
| intention was to allow for 3-bar electric fires to be
| operated as 13A loads, and be moveable between rooms.
|
| Rings are more complex to test, and have nasty failure modes.
| I'd argue that they should only be used in said small flats,
| and that 20A bus/radial runs should be used in larger builds.
| i.e. any modern house, rather than a flat. Said run the
| supplying all of the sockets in any given room, it does
| though require a larger "consumer unit".
|
| The rings have a 30A (or now 32A) at the "consumer unit"
| (distribution fuse box) with two cables running in a loop
| around all sockets in the circuit. The cables have
| traditionally been 2.5mm, and open clipped, so rated at
| around 27A (based upon preventing overheating).
|
| Hence when operating properly, the wiring in the circuit can
| carry 54A, the circuit is fused at 30A (or 32A) to protect
| the cable, and an individual load is limited to 13A (being
| the highest cartridge fuse commonly available).
|
| Have a look here:
| https://www.diydoctor.org.uk/projects/cablesizes.htm
| mytailorisrich wrote:
| There may be several circuits, and they all have independent
| breakers. Certainly, an electric cooker/oven will be on its
| own circuit as it has higher requirements.
|
| Then, standard ring circuit is 32A, and individual sockets
| are limited to 13A (via fuse in plug). So you will need to
| have 2 kettles on on the same circuit and then add a third
| device pulling not an insignificant amount of power (32 -
| 2x13 = 6A) before the breaker trips. This will be safe if the
| ring circuit is not faulty as they are usually wired with two
| 2.5mm2 cables (two because it's a ring) that have a standard
| rating of 24A each...
| housemusicfan wrote:
| UK electrics are mad - with the ring main and what not
| requiring fuses in the enormous plugs. All vestiges of
| post-WWII design. By code a modern American kitchen must
| have:
|
| - dedicated 50A 240V for an electric stove or oven (unless
| gas service is present)
|
| - dedicated 20A 120V each for the fridge, microwave,
| dishwasher, disposal (the latter being uncommon outside the
| US and Canada). The last two often share a circuit.
|
| - two 20A countertop circuits with GFCI protection (what
| the Brits call 'RCD' - the difference being ours trip at
| 5mA vs 30mA and won't knock out half the house.)
| laurencerowe wrote:
| My apartment in San Francisco which I pay an absurd
| amount of money for has just two or three 20A circuits in
| total going by the breaker. I regularly trip the power.
| bluGill wrote:
| How old. What you describe sounds like it was built
| before 1970 and never updated to modern standards. Since
| the wire is often in okay shape few consider it worth the
| cost to replace it even though it really can't supply
| enough power for modern uses. (often you have to replace
| it all as if you touch it the insulation will break and
| then it isn't okay)
| laurencerowe wrote:
| Built around 1910 I think but the wiring is definitely a
| lot newer than that, 70s or 80s at a guess. They just
| didn't put many circuits in.
|
| Has never been an issue anywhere I lived in the UK. As I
| understand it they have been putting in 30A/230V ring
| circuits as standard for 75 years now.
| iso1631 wrote:
| You assert that it's mad but then describe a mad
| situation in the US.
|
| A typical British kitchen will have a ton of sockets
| (although never enough), to plug in a fridge (or two, or
| three), a microwave (or several - they rarely goes about
| 1kW anyway), a dishwasher, a washing machine, a tumble
| dryer (UK kitchens tend to have washers and dryers,
| rather than bathrooms. Larger houses have separate
| utility rooms)
|
| The only thing on a dedicated circuit would be a hard-
| wired oven.
| housemusicfan wrote:
| Thinking that having dedicated independent circuits is
| madness sounds like Stockholm syndrome. The point being a
| single faulty appliance won't knock out the lights and
| sockets to half the house simultaneously (a common
| occurrence during a fault in the UK, especially the RCD).
| It's also quite convenient to switch off a single
| appliance for service. Yes British sockets are all
| switched but not necessarily in a convenient location.
|
| A software analogy would be running all your services on
| separate VMs, as opposed to running them all on a single
| server which could go down at once.
|
| Brits don't even put outlets in the bathroom, minus a
| current-limited transformer-isolated one for an electric
| razor.
| mytailorisrich wrote:
| Ah, the regs have changed and we can now have a full
| socket in the bathroom as long as it's far enough from
| the bath (.6 + 2.5 = 3.1m from edge of bath), which rules
| out most bathrooms...
| housemusicfan wrote:
| I assume the temptation to use the electric tea kettle
| whilst having a bath is too great...
| sph wrote:
| Thanks, that's incredible. I won't have to worry about
| tripping the circuit breaker anymore.
| mananaysiempre wrote:
| > in Italy most residential circuit breakers have a limit of
| 3.3 kW
|
| Wait, really? That's seriously underpowered, though I guess
| if you never need electric stoves or heating it could be
| somewhat usable. An ex-Soviet big-city apartment building
| will usually support 40A (~9kW) per apartment, and in France
| I had the impression that the values were similar--except for
| student dorms, which are supplied and wired like apartment
| buildings despite the density of occupants being 3x that or
| more, because apparently the builders could not into
| engineering and the uni authorities find it easier to blame
| the occupants (yes, I'm still a bit salty about that).
| sph wrote:
| I haven't lived in Italy for 10+ years, so I don't know if
| anything has changed since, but that was the limit for all
| houses I've lived in, and from a quick Google search, it
| depends on your contract -- the lowest is a 2 kW limit, 3.3
| kW is the most common, and you can ask for an increase for
| an additional monthly fee. Heating and stoves are usually
| gas-powered, we don't do electric except for water boilers.
|
| I have always wondered if those limits and the high
| electricity costs are because Italy abolished nuclear
| energy post-Chernobyl, doesn't have a massive oil and gas
| operation, so most of it is imported at a premium.
| gulikoza wrote:
| That ~9kW is probably split over 3 phases. Here you have
| 3x20A main breakers and then each circuit has a 10A or 16A
| breaker. So about 3.7kW limit for larger appliances (16A *
| 230V) on a single circuit, but should not exceed 20A on one
| phase. Stoves can be connected to 2 phases, 400V and get
| 7.2kW.
| mananaysiempre wrote:
| > That ~9kW is probably split over 3 phases.
|
| In the Soviet system, usually not. There are often
| several downstream circuits with their own 20A or so
| breakers and wiring (e.g.: kitchen stove, normal kitchen
| sockets, bathroom sockets and lighting, other rooms'
| sockets, everything non-wet lighting), but each apartment
| is normally supplied from a single phase. On the other
| hand, different apartments on the same floor (or
| different single-family homes on the same street, etc.)
| might indeed be supplied from different phases. Normal
| (Schuko) wall sockets are most frequently 16A (so yes,
| 3kW kettles max), stove sockets (and circuits) might be
| up to 32A, still single-phase.
|
| (That's not to say the system is ideal, of course. E.g.
| GFCIs have become common only in the past fifteen years
| or so, and in a country-home setting I've actually
| encountered disposable screw-socket [IEC 60269] fuses.)
| N19PEDL2 wrote:
| > Wait, really?
|
| We should thank whoever came up with the idea of abolishing
| nuclear power in Italy. What a big mistake!
|
| > if you never need electric stoves or heating it could be
| somewhat usable
|
| Heating and stoves in Italy are usually gas-powered. Ovens
| and kettles are electric but normally do not exceed 3.3 kW,
| however, we need to be careful not to use too many high-
| consumption appliances together (e.g., oven and washing
| machine).
|
| The introduction of increasingly restrictive energy classes
| for electric appliances in recent years has mitigated the
| problem to some extent anyway.
| pjc50 wrote:
| Italy has almost the same per-capita electricity
| consumption as the UK. I suspect any residential
| limitations are made up by industrial and transport
| usages.
|
| You guys really need to get on the solar panels, though.
| jedberg wrote:
| I have a question for you as a Brit. I live in an Asian
| household (my wife is Asian). We have a hot water boiler, as
| most Asian households do. It keeps 4L of water at "tea"
| temperature at all times (after boiling it).
|
| When we want tea, we just fill up the cup with the already
| boiled and ready water. It's super efficient because it's super
| insulated so it barely takes any energy to keep it hot after
| it's been boiled.
|
| Why don't Brits (and other tea drinking cultures in Europe) do
| this?
| laurencerowe wrote:
| What is tea temperature for you? As I understand it black tea
| which Brits drink should be made with water at close to
| boiling (100 C) while green tea should be made with water at
| 80 C.
|
| My pet peeve in the US is ordering a cup of tea and getting a
| cup of cooling water and a teabag by the side. Fine for
| herbal or green tea but terrible for black tea.
| jedberg wrote:
| My boiler lets me set the hold temp at 208f(97.8C),
| 195F(90.5C), and 175F(79.4C). So basically you can do all
| the different "ideal" temps depending on which tea you make
| the most.
|
| We keep it at 195 since we don't make black teas, and then
| we can let it cool down to whichever tea we want or just
| mix it with some filtered cold to get it to temp.
| hot_gril wrote:
| My pet peeve is ordering hot tea and finding out they only
| have coffee or iced tea. I've also gotten hot tea in a
| plastic melting cup a few times.
| bjornasm wrote:
| >Why don't Brits (and other tea drinking cultures in Europe)
| do this?
|
| Because it is better to boil the right amount of water to the
| precise temperature when you need it, as it takes virtually
| no time.
| davnn wrote:
| At least in the German-speaking market there exist said
| solutions, but they are not very common (yet?). I believe
| keeping 4L at near boiling temperature is still less
| efficient than individually heating and it takes less than a
| minute with 3kW.
| L_226 wrote:
| Now all the German speaking market needs is tea that
| actually tastes good.
| walthamstow wrote:
| Some do. It's become a popular addition to a middle class
| kitchen. All offices have them.
|
| As to why Asian households have it and we don't, I think it's
| simply that we have been boiling water in kettles since the
| stoves ran on coal, and the electric kettle is just an
| upgrade of that same old system
|
| Not to mention the age of our housing stock. The Asian
| households you refer to, when were their homes built? I'm
| guessing much more recently, comparatively speaking.
| fragmede wrote:
| Why is the age of the housing stock relevant here? An
| Japanese-style water boiler is an add-on kitchen appliance,
| like the Instapot or an air-fryer, so, cultural differences
| aside, you'd expect similar adoption rates. Given that we
| haven't, there must be some cultural component as to why.
| desas wrote:
| Some people have instant boiling water taps with tanks,
| they're not unknown but rare and becoming increasingly
| less so. I think this is because a) they're relatively
| new here and b) last time I looked they cost about PS1k
| plus fitting.
|
| The Japanese water boilers look like they cost PS200ish
| (vs PS15 for a kettle) and are bulkier than a kettle.
| They will save practically no time - kettles boil fast
| here and while they're boiling it gives you time to put
| the tea in and any other preparations.
| jedberg wrote:
| It just occurred to me that Japan also uses 120V
| (actually I think they use 100V), so it may be just a
| matter of speed. You can boil water a lot quicker with
| your 240V outlets than we can with our 100-120V.
| bluGill wrote:
| Age matters because in many cases the house was built
| with some expectations, and something else won't work at
| all. In the 1950s your house got a total of 4 circuits,
| which was enough for clocks and lights, one fridge, and a
| kitchen mixer (an electric range was an option and added
| circuits). Of course TVs arrived in the 1950s (they
| existed before then but were not common) and started
| blowing power budgets. As people started using more
| electric new houses got upgraded to handle those loads,
| but many older houses have not been updated as it is
| expensive (major remodel as you need to tear down walls).
|
| Of course the above is standard, not everyone takes the
| standard. However it is unusual to take something else.
|
| Builders (read electric codes) build for what is common
| uses. If everyone wants an something that uses a lot of
| power the wires will be made to handle that in new
| houses. However if you want that same thing in an older
| house you may discover that the rewiring needed makes it
| not worth it and so you look for an alternate.
| desas wrote:
| I'm not sure that's exactly true in this context. At
| least, I've never been in the house in the UK where the
| electrics in the kitchen couldn't handle a kettle, and a
| water boiler for hot drinks isn't likely to use more.
| mhandley wrote:
| According to Twinings tea:
|
| _Always use freshly drawn (filtered if possible) cold water
| in the kettle. Tea loves oxygen as it helps the flavour
| develop._
|
| _Most of us are guilty of the following... looking at the
| kettle seeing there is some old, used water in there and
| simply re-boiling._
|
| _If you keep re-boiling the water in the kettle, it loses
| all of its oxygen and you'll be left with a really flat cup
| of tea._
|
| _If you boil the kettle with fresh water, you'll have a
| delicious cup of oxygenated tea that tastes divine._
|
| https://twinings.co.uk/blogs/news/how-to-make-a-cup-of-
| tea-p...
|
| I'm not sure how much difference this makes, but when I use
| the hot water boiler at work, the tea definitely tastes
| slightly off compared to using a kettle at home. But it's
| also possible the hot water boiler at work is not producing
| hot enough water.
| benhurmarcel wrote:
| Honestly if it's to put Twinings in it, it doesn't really
| matter.
| housemusicfan wrote:
| They do make such a thing as an instant hot water
| dispenser, though they are considered a luxury and not very
| common:
|
| https://insinkerator.emerson.com/en-
| us/shop/insinkerator/ins...
| ReptileMan wrote:
| Just put it in the blender for a while.
| Astronaut3315 wrote:
| An Asian style water boiler maintains the temp just below
| boiling, so there isn't any reboiling throughout the day.
| Think of it as a water boiling thermos.
|
| You're meant to replace the water daily. Not sure how many
| follow that guideline.
|
| ETA: Only the so-called "hybrid" models have vacuum
| insulation. It's worth the extra charge.
| scotty79 wrote:
| Warmer water loses dissolved gasses faster.
| jedberg wrote:
| But as it cools the gasses reintegrate. So I'm not sure
| the science backs this up. Water at the same temp should
| have the same amount of dissolved gas regardless of how
| it got to that temp (given enough time for the gas to
| reintegrate).
| mindslight wrote:
| I think you're incorrectly discounting that time aspect.
| If you leave a glass of tap water sitting out, eventually
| there will be a bunch of bubbles clinging to the sides of
| the glass. This doesn't happen immediately, but rather
| over many hours. Similarly, I would think that boiling
| water won't reach its gas equilibrium during the course
| of making tea, but hot water sitting around waiting to be
| used will.
| jrockway wrote:
| I agree with this. I develop my own film and the way I
| manage water is to boil it, put it into sealed bottles,
| and store those in the fridge. This avoids bubbles more
| readily than just using tap water (which is over 20C in
| the summer anyway, which is why I do the refrigeration
| thing). No, I don't have an aerator on my tap either.
| Obviously that introduces a lot of bubbles.
| jedberg wrote:
| It's true that boiling water reduces dissolved oxygen, but
| cooling water takes on dissolved oxygen.
|
| So I don't think the science backs this up.
| mrguyorama wrote:
| Nearly all tea advice is ideology and superstition,
| explicitly because most people like different things
| about tea. There cannot be a right answer for such a
| personal preference.
|
| Make tea such that you enjoy it. Same as coffee.
| markdown wrote:
| Agreed. You can't beat good old Nescafe instant coffee.
| Starbucks just can't compare.
| eep_social wrote:
| Hmm, I don't seem to be able to go back and delete this
| comment.
| psd1 wrote:
| The hot urn cannot be more efficient than boiling the correct
| amount of water each time.
|
| The limiting factor is the specific heat capacity of water.
| If daily consumption is 2l, you have to put in the joules to
| raise 2l to boiling, either way. If you have heat losses
| during the day, there's your inefficiency.
| jedberg wrote:
| It is of course less efficient. I never said it was more
| efficient. But it's more convenient.
| bialpio wrote:
| Your comment literally says "It's super efficient"
| though.
| jedberg wrote:
| Sure, but that doesn't imply it's more efficient than the
| other options. Just that it's also very efficient.
| HDThoreaun wrote:
| How many people are boiling the correct amount each time
| though? I fill my jug up all the way and then keep
| reboiling which seems less efficient as the boiled water
| keeps cooling down.
| shrx wrote:
| Why wouldn't you boil just the amount that's needed?
| Boiling the whole container is unnecessarily wasteful.
| zbrozek wrote:
| I use my target cup to measure out how much water to
| boil.
| hot_gril wrote:
| I fill it to a certain mark every time. Not that I'm
| trying to conserve energy, I just don't want to leave
| extra water sitting.
| porbelm wrote:
| Legionella
|
| I kid, but there's something about "fresh" water probably?
| jedberg wrote:
| The water stays way above the temp for legionella. And the
| water is still pretty fresh, it ends up getting replaced
| every other day or so in winter. And in summer we just
| replace it once in a while anyway.
|
| Also it will reboil after a certain amount of time.
| Astronaut3315 wrote:
| I've had a 4L Zojirushi boiler in the US for about 15 years
| now. This is the best solution for those who complain about
| 120V kettles.
| awalach wrote:
| Obligatory TechnologyConnections reference -
| https://www.youtube.com/watch?v=_yMMTVVJI4c TLDR: in US it
| takes 2 minutes more :). Is that difference that noticeable
| IRL?
| bemusedthrow75 wrote:
| If you were British, you would not need to ask this.
|
| Being compelled to wait two minutes more to boil a kettle for
| a cuppa would be enough to provoke an armed rebellion.
|
| Not even sure I'm kidding.
| creole_wither wrote:
| Why not just keep the water warm in an electric samovar?
| bemusedthrow75 wrote:
| Typical British teabag tea -- the stuff we consume in
| quantity -- is brewed with water just off the boil, and
| consumed often pretty quickly afterwards because cold
| milk gets added.
|
| (Or it goes into a teapot for brewing, and again needs to
| be just off the boil for that)
|
| Given that we can boil a kettle for a mug's worth of tea
| in not much more than half a minute, there's no reason to
| use them, I think.
| mrguyorama wrote:
| Most Americans drink substantially more coffee than tea,
| which is why we have a purpose built appliances for making
| coffee, and have had those for decades.
|
| The reason Americans don't have a super fast boiling kettle
| is that very few Americans WANT a very fast boiling kettle
| for large portions of water. If an American wants a cup of
| tea, two minutes or less in the microwave is sufficient. I
| don't care if you think that's bad, because I want a cup of
| tea, not some elitist purity contest.
| zoenolan wrote:
| Well you have to remember the UK is the nation that fit
| kettles in Tanks
|
| https://en.wikipedia.org/wiki/Boiling_vessel
| mrguyorama wrote:
| People like to joke about this but the reason it's called a
| "boiling vessel" and not a "Tea maker" is because it's
| incredibly useful other than just making tea, to the point
| that the US has also added them to many modern vehicles.
|
| On demand hot water, from the safety of your combat
| vehicle, is a genuine war innovation on the same level as
| canned food. Especially now that combat vehicles are aiming
| towards having more robust electrical systems makes it
| trivial to implement. Hot water means hot food, means
| warmth on a cold day, means sterilizing sketchy water
| sources without chemical tablets, means you don't have to
| light a visible fire to make your coffee, means you keep
| morale way higher. Your troops are now cleaner, better fed,
| happier, more motivated.
| dfxm12 wrote:
| On the hot beverage topic, I'm jealous that the espresso gear
| in Europe is a little cheaper/faster. The motors that drive
| coffee grinders and the heaters that heat up water in the
| boilers work a lot easier/faster.
| HALtheWise wrote:
| Has anyone ever made a battery-powered kettle with
| significantly higher power than can be pulled from a wall
| outlet? Modern lithium batteries can deliver many kilowatts of
| power, and given that the total _energy_ needed to boil the
| water is basically fixed, the battery size requirements might
| be pretty reasonable. I wouldn 't be surprised if boiling water
| in 15s is possible even on a 120v American outlet.
| mhandley wrote:
| Now I realize that what I really want to build is a kettle
| with two 3kW heating elements. On a UK ring main, I can plug
| the two elements into two neighbouring sockets and still have
| headroom before I blow the breaker. I can cut my time-to-tea
| from 45 seconds to 22 seconds!
| kccqzy wrote:
| I think it's certainly possible. FWIW car batteries can often
| support 1000A especially those for large diesel engines. They
| aren't meant for continuously loads or deep cycles though.
| Marine batteries may be able to overcome this.
| jaywee wrote:
| Impulse Labs, a startup, is doing lithium-backed kitchen
| stoves. Claims to heat-up 1L of water in ~40secs. That's at
| least 8.6kW.
|
| https://twitter.com/sdamico/status/1592553611879673856?s=20
| adrianmonk wrote:
| It does seem feasible to equal the performance of a 3
| kilowatt kettle with batteries!
|
| =-=-=
|
| Question #1: Can we get 3 kilowatts of power out of some
| lithium ion batteries?
|
| There are high-current versions of lithium batteries.
| Conveniently, they're widely available because they're used
| for vaping.
|
| I found a battery that looks reasonable
| (https://www.18650batterystore.com/products/molicel-p42a).
| Its stats: 4200 mAh capacity, 3.6V nominal, 45A continuous
| discharge, and retail cost $4.99.
|
| At 3.6V and 45A, each battery should output 162 watts.
| Rounding to 150 watts, we'd need 20 of them to make 3
| kilowatts. So $100 worth of batteries.
|
| =-=-=
|
| Question #2: How long will they last? Long enough to boil
| water?
|
| At the 45-amp discharge rate and with 4.2 amp-hour capacity,
| it should take 4.2/45 hours = 6 or 7 minutes to discharge
| them.
|
| By my math, it takes 335 kilojoules to heat a liter of water
| from 20degC to 100degC. A 3 kilowatt kettle should be able to
| do it in 335/3 = 112 seconds.
|
| So the batteries should be able to boil water around 3 times
| before discharged.
|
| =-=-=
|
| Those calculations are for running on battery alone. Since
| you can get 1500W out of an American 120V outlet, you could
| make a kettle that draws 1500W from the wall and boosts it
| with 1500W of battery power. (I'd use two heating elements.)
| Then you only need $50 of batteries.
|
| The kettle is going to be a bit heavy, though. The batteries
| are 70g each, so 20 of them is 1.4 kg. Also, I don't know
| much batteries heat up when cranking out 45 amps, but I bet
| the answer is a lot, and you may need active cooling and/or
| thermal shutoff.
| p1mrx wrote:
| I would like to see a US electric range with Schuko outlets and
| 16A GFCI breakers on the side, but that probably violates too
| many electrical codes.
|
| Schuko makes the most sense because it's unpolarized, so
| appliances don't expect a neutral leg. You still have the 50/60
| Hz problem, but something like a kettle probably won't care.
|
| Or there could be a countertop "Schuko dongle" that attaches to
| the screw terminals on the back of an existing range, if it
| weren't for those meddling codes...
|
| Though in practice, the key to boiling fast is to use less
| water. A 1500W kettle with 500 mL minimum fill is totally
| reasonable for cup of coffee/tea.
| dfawcus wrote:
| It's not 230, it is 240!
|
| 3000 / 230 = 13.04
|
| 3000 / 240 = 12.5
|
| We fit 13A fuses to the plugs of kettles. At 230V the tolerance
| would be too close.
|
| Whereas in reality, a kettle designed to be 3kW at 240V would
| only be 2.755kW at 230V, or 2.520kW at 220V.
|
| You'll often find the latter pair of number printed on the base
| of the kettle. i.e. 2520-3000W at 220-240V.
| djaychela wrote:
| They generally don't blow at the rated current. I've reliably
| used a 13A fuse on something that draws 16A for a while when
| starting up and never had a problem. Obviously RCDs etc are
| more accurate, but wired / cartridge fuses are always under-
| rated, in my experience.
| bluGill wrote:
| Most fuses are slow blow - they will allow somewhat over
| the rates power draw for a while before blowing. Many
| things (motors) take a lot more than rated current for a
| few seconds and this is perfectly safe so the fuse
| shouldn't blow. The purpose of the fuse is to prevent a
| house fire, if your wires are good for 13 amps that means
| at 100% duty cycle, you can draw 16 amps for "a while"
| before the wires get hot enough to burn the house down, so
| long as you drop under 13 amps for "a while" so the wires
| cool down and never get hot enough to start a fire the fuse
| is working.
|
| Note that the above is about safety. If you are going to
| draw 16 amps you should stick to a circuit rates for that,
| as it will have less resistance and thus waste less energy.
| myrandomcomment wrote:
| https://www.youtube.com/watch?v=_yMMTVVJI4c
|
| The difference is 2 minutes on the boil time of 1L.
| lbourdages wrote:
| I have 20 amp sockets in my kitchen (as all newly built housing
| has, really) but there are no 20 amp kettles on the market. I
| wish I could get that extra 600 watts or power :(
| Astronaut3315 wrote:
| _In theory_ you could use one of those Leviton British-style
| receptacles designed for US-style boxes on a dedicated 240V
| circuit.
|
| In practice, NEC code likely prohibits you from doing this.
| bombela wrote:
| I would install an US 240V@20A receptacle and replace the
| plug on the kettle.
|
| You can also wire a duplex 120V with the two phases (you
| might find this in some kitchens, and in my workshop). Then
| you can make a dangerous extension cord adapter combining
| the split phase 120V into one 240V female plug.
| brocklobsta wrote:
| In the US it is against code to have any regular appliance
| use more than 15 amps continuously I believe
| lbourdages wrote:
| My hair dryer is rated for 1875W - a bit over 15 amps at
| 120V.
| pjc50 wrote:
| The standard British kettle is 13A .. at 240V.
| mindslight wrote:
| If you're referring to the standard 80% continuous load
| rule, it's 16 amps. But I wouldn't think a kettle would be
| considered a continuous load.
|
| If I wanted a British kettle in the US I'd wire up a 6-20R,
| buy a British kettle, and swap the plug.
| bitbckt wrote:
| The circuit rating is 80% of nominal for continuous loads -
| runtimes of 3 hours or more - according to NEC in the US.
| Not sure what you mean by "regular appliance"; there is no
| such definition by code.
|
| A kettle is fine at a full circuit load for under 3 hours.
| macrolime wrote:
| Your run your kettle for hours on end?
| AlgorithmicTime wrote:
| [dead]
| vel0city wrote:
| A kettle is not a continuous load.
| SkyPuncher wrote:
| Continuous is anything outside of a small "startup
| window". Appliances with motors will often have an
| initial surge amperage that's higher than peak.
|
| Fuses/breakers are ultimately about heat control. They
| can run "indefinitely" at their rated amperage, but can
| support short, higher loads.
| rootusrootus wrote:
| There are regional differences that are probably causing
| some confusion. In the US, breakers have a nameplate
| rating 25% higher than their continuous load capacity. Go
| to Australia, for example, and the identical breaker will
| have a nameplate rating 80% of what it would in the US.
|
| So you can run indefinitely at the nameplate rating in
| Australia, but only 3 hours in the US. And the startup
| current (inrush) can be _much_ higher than the rating.
| Most breakers are thermo-magnetic. The magnetic part has
| a much higher tripping point and allows for inrush
| current. The thermo part trips when it gets too hot, and
| that 'll be the current printed on the breaker.
| bitbckt wrote:
| No, continuous is very specifically defined in the NEC as
| 3 hours or more of runtime.
| SkyPuncher wrote:
| This article does a good job of explaining how failure
| modes/alternative usages can make that definition fuzzy:
| https://www.csemag.com/articles/understanding-
| overcurrent-pr...
|
| Practically speaking, any intermittent device that _can_
| run continuously or can fail to a continuous needs to be
| considered as such for safety purposes.
|
| For example, a fridge should only run the compressor
| intermittently, but it has two obvious cases where the
| compressor could run indefinitely:
|
| * An influx of heat, like filling an empty fridge with
| room temperature cans.
|
| * A door being left open.
|
| In the case of the kettle, it will likely be evaluated
| against it's "nominal" draw after the initial startup. If
| the auto-off sensor were to fail, it could run
| continuously at the tempurature.
| bitbckt wrote:
| I probably can't speak to your jurisdiction, but no
| electrical inspector I've ever met would consider those
| loads continuous - in its precise, non-colloquial meaning
| - for the purpose of rating the circuit.
|
| An appliance manufacturer may be under different UL
| regulations for failure modes of a device on a specific
| rated circuit. I don't know anything about that.
| fragmede wrote:
| Yes, laymen and non-experts are going to use words to
| mean the wrong thing. NEC defines continuous load as 3 or
| more hours of uninterrupted demand. If you want to use
| the amateur definition, go right ahead, but understand
| there's an accepted industry definition of that term,
| even though it looks just like normal words. :)
| vel0city wrote:
| If this is the standard then everything is a continuous
| load. A soldering iron or a hair dryer or a blender might
| get left on forever, who knows. Maybe I want the
| microwave to run 24 hours a day. If everything is a
| continuous load, why would the NEC make a difference at
| all?
| mindslight wrote:
| Even in the context of your refrigerator example (which I
| don't necessarily agree with), a kettle should have two
| thermostats - a primary one that keeps the temperature
| setpoint, and a safety cutoff in case the primary stops
| working. In both fail and the kettle is somehow drawing
| its nominal power for hours at a time, the main safety
| hazard is going to be the kettle itself trying to
| dissipate >1Kw.
| dfawcus wrote:
| Well they can be, until they boil dry, and the thermal
| cut out kicks in.
|
| Prior to the late 70s / early 80s so called "automatic
| kettles" were not necessarily all that common in the UK,
| and one had to manually switch them off.
|
| I certainly recall a time or two with a kitchen full of
| steam due to forgetting about putting the kettle on.
| Kirby64 wrote:
| No it's not. It's just against code if they use a NEMA 5-15
| outlet. If GP used NEMA 5-20 outlets and the appliance used
| a 5-20 plug, then there's no issue.
|
| Many commercial appliances use 5-20 plugs. Also, lots of
| commercial cleaning equipment seems to use 5-20, which is
| why you see businesses tend to only use 5-20 outlets.
|
| I'm not aware of any kettles that use 5-20 plugs but I bet
| they exist somewhere.
| lbourdages wrote:
| Yep my kitchen outlets are all the 20-amp specific ones,
| with the T slot.
| fragmede wrote:
| It's not, and for laymen "continuous load" has a specific
| meaning in this context. It means something that runs for
| 3+ hours continuously, without a break.
| fragmede wrote:
| Just get a Japanese-style hot water boiler. They're way
| faster.
| izolate wrote:
| I used to sympathize with this take until I bought a Zojirushi
| water boiler, which provides instantaneous hot water. Now even
| a faster kettle is a downgrade in experience.
| hot_gril wrote:
| Somehow I've never considered my home kettle too slow in the
| US, even though I have tea probably 2-3 times a day. And
| there's an instant hot water machine at our office, so it's not
| like I've gotten used to slowness.
| perfectstorm wrote:
| i wish 240V was more common. i can't charge my EV at a reasonable
| rate and it would cost me $15k+ to install a 240V in my detached
| garage (requires trenching).
| tzs wrote:
| Could you do the trenching yourself?
|
| I don't know where you are, but in the US a walk-behind
| trencher rents for under $500 per day [1] [2] [3] [4].
|
| [1] https://www.sunbeltrentals.com/equipment-rental/earth-
| moving...
|
| [2] https://www.compactpowerrents.com/rental-
| equipment/trencher/...
|
| [3] https://www.compactpowerrents.com/rental-
| equipment/trencher/...
|
| [4] https://www.compactpowerrents.com/rental-
| equipment/trencher/...
| [deleted]
| Anon_Forever wrote:
| >i wish 240V was more common
|
| More common where? Your main service panel is 240V. Do you only
| have a single 120V circuit feeding your garage?
| somat wrote:
| Really all residential connections in the US are 220V split
| phase. The nice thing about split phase is that it is easy to
| well... split and run two linked 110V circuits, so most houses
| will have a few 220V items(ovens, airconditioner) and the rest
| wired half with phase A the other half with phase B. all of our
| consumer items expect this 110V
|
| As to why split phase.... I am not really sure. Really, I wish a
| three phase residential had become normal instead. All the
| advantages of split phase but now your motors don't have to suck.
| I have heard a three phase residential connection is common in
| some parts of Germany, lucky bastards.
|
| One interesting side note is how the US last mile distribution
| layout is different than germany. The US uses a lot more smaller
| transformers, really one per street. while germany uses fewer
| larger transformers, one per neighborhood. not sure which one is
| better I bet the german layout is more efficient. but I will note
| it is a lot easier to keep spares and change out a small
| transformer.
| linsomniac wrote:
| I thought residential US service was 240V split phase with two
| 120V legs.
|
| I've heard for some wet construction locations they'll set up
| 120V split phase with two 60V legs, to keep the potential to
| ground smaller.
| bootlooped wrote:
| When talking about the voltage of US residential service, and
| the devices that use it, 240 and 220, and 120 and 110 are
| functionally the same. The house theoretically has 240v and
| 120v power, but voltage may sag throughout the home's wiring,
| and some outlets will a real voltage reading lower than
| 240/120.
| pacaro wrote:
| > but I will note it is a lot easier to keep spares and change
| out a small transformer.
|
| In my neighborhood, about once a year there's a loud pop, or
| quiet bang, and a bunch of houses lose power. The electric
| company will fix it pretty quickly.
|
| I think that it's performing selection pressure on the
| unlicensed squirrel electrician population.
| dylan604 wrote:
| Growing up in the sticks, I'm pretty sure there was an
| unlicensed trade school for squirrels in the area. Pretty
| much once a year, we'd need a replaced transformer from one
| of these unlicensed squirrel electricians. I never charted
| the timing of the year this would happen, but now I wonder if
| aligned with the start of a new class.
| kefabean wrote:
| Here in the UK I think some of those unlicensed squirrel
| electricians are beginning to retain in fibre broadband
| installations. My neighbour was 'disconnected' last week.
| dylan604 wrote:
| The next time a friendly representative from the
| international brotherhood squirrel electrical (IBSE)
| union stops by to discuss joining their service
| protection plan, they should reconsider. "This a real
| nice connection you have here. It'd be shame if something
| were to happen to it"
|
| Edit: or would that be the Free Mesons
| Spooky23 wrote:
| Depending on where you live, they age out too. The one behind
| my house exploded a year or two ago.
|
| It was manufactured in 1959!
| kelnos wrote:
| I was a little surprised that my neighborhood must have some
| redundancy. A year or so ago a transformer on a pole two
| doors down from us popped, and our power actually didn't go
| out.
| user2342 wrote:
| > I have heard a three phase residential connection is common
| in some parts of Germany, lucky bastards.
|
| Not some parts. It's common in all parts of Germany - and I
| think even common on the whole EU.
| mschuster91 wrote:
| > I have heard a three phase residential connection is common
| in some parts of Germany, lucky bastards.
|
| German here. Virtually all houses built after the 60s will have
| _at least_ 3x63A @ 230V (L-N) / 400V (L1-L2/L2-L3/L3-L1) AC.
| Individual flats/apartments/studios from before the 90s will
| usually have a single phase 32-40A uplink, so in a 12-unit
| house you'll have four flats wired to L1, four to L2, and the
| last four to L3 to ensure even load across the phases. More
| recent builds that don't have gas stoves any more will have a
| 3x40 connection to allow for powerful electric stoves and
| ovens.
| askvictor wrote:
| Nice over-provisioning; I doubt the gas shortage or electric
| cars were on the radar when 3 phase became the norm...
|
| How are loads balanced to phases in a standalone house?
| mjan22640 wrote:
| > I have heard a three phase residential connection is common
| in some parts of Germany, lucky bastards.
|
| Czech Republic switched to 3 phase 380V in 1919. I guess the
| transition DC -> 110V AC -> 3 phase ~400V went quick everywhere
| in the world, just in US they did not do the last step.
| melenaboija wrote:
| > The US uses a lot more smaller transformers, really one per
| street. while germany uses fewer larger transformers
|
| I am from Spain and living in the US and something that was
| shocking to me about it is that here, at least where I lived,
| these last transformers are hanging from poles and every now
| and then I can hear an explosion and it is one of them blowing
| up.
|
| I have no idea but, maybe being exposed like they are here in
| the US makes them more vulnerable to weather conditions and
| that makes them explode? Or maybe it simply is that in Spain
| they also explode but the fact of not being that close to
| residences makes it harder to hear it.
| bluGill wrote:
| Transformer explosions are rare. Unless you can produce
| statistics saying otherwise it is safe to assume they happen
| as often in both countries (per something, the US obvious has
| far more transformers given larger population and area, and
| thus should have more total)
| TheCleric wrote:
| Yeah near me they rarely ever pop, and when they do it's
| almost always lightning related.
| Symbiote wrote:
| "Rarely ever" and "when they do" suggests this happens
| more often than "I've never heard of this as a thing"
| here in Europe.
|
| With higher voltages, fewer transformers are needed.
| Power lines are buried, and transformers are generally
| larger and not exposed to weather.
| melenaboija wrote:
| That was exactly my point, I have never heard that in
| Europe and I would say at least a dozen of them in US in
| a decade. Probably because there are more of them and
| exposed.
|
| I am not criticizing the infrastructure but as European
| (and this is something others told me) it feels weird to
| see transformers hanging from poles and every now and
| then blowing up.
|
| And I mentioned the weather because my experience is that
| it usually happens during storms, it might be lightnings
| or tree branches but that is what I have seen.
| Symbiote wrote:
| For some statistics, "U.S. electricity customers averaged
| seven hours of power interruptions in 2021." [1].
|
| At first I couldn't find equivalent European statistics,
| until I changed my search to "minutes", which is how Europe
| measures outages. The EU average in 2010-2014 was just over
| 2 hours, and as low as 29 minutes in Germany, or 20 here in
| Denmark.
|
| [1] https://www.eia.gov/todayinenergy/detail.php?id=54639
|
| [2] https://neon.energy/Neon_Data-quality_European-
| Commission.pd... (22nd page, figure 5)
| [deleted]
| _trampeltier wrote:
| The cool thing is in Switzerland with the T15 / T25 plug you
| can use from a small 230V LN plug, 230V LNPE plug or a 3x400V
| 3LNPE plug. You see this often in workshops. I think this is
| unique in the world.[1]
|
| Also the 3xT13, 3 plugs where everywhere else in the world is
| just one plug. [2]
|
| [1] https://de.m.wikipedia.org/wiki/SN_441011
|
| [2] https://hager.com/de-ch/katalog/produkt/wh22730700k-ka-eb-
| st...
| jhoechtl wrote:
| > 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.
| gumby wrote:
| > 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... (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/
| dghlsakjg wrote:
| You 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.
| sokoloff wrote:
| Far 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.
| kukkamario wrote:
| 400V 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 wrote:
| There 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 wrote:
| [flagged]
| robswc wrote:
| No idea if you're from the US but this "weak
| infrastructure" has/is hosted/hosting nearly every
| important infrastructure that makes the online world go
| round and has been doing perfectly fine for decades.
|
| What are you doing that you need 400v?
| hot_gril wrote:
| > What are you doing that you need 400v?
|
| Complaining about Americans on the internet, obviously.
| FLT8 wrote:
| I am in Australia and am in the process of having our
| home supply wired for three-phase 415v. Everything is
| heading down the path of electrification. Where
| previously we had gas central heating, cooking, and hot
| water, we are replacing those with electric HVAC (30amp
| circuit @ 240v, admittedly rarely driven that hard),
| electric instantaneous hot water (40 amp @ 240v),
| induction cooktop (32 amp), oven (15 amp), and also
| introducing a car charger (total approx 45 amps across
| the three phases).. it's likely at least the HVAC,
| cooktop/oven, car charger, and hot water could be on at
| or around the same time, which would result in more power
| draw than a standard single phase connection here (80a)
| could supply. It's not that it's needed _all_ the time,
| but it 's helpful to have the headroom a 3-phase supply
| can provide.
| deaddodo wrote:
| [flagged]
| pavlov wrote:
| The 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 wrote:
| yes, but who invented the americans
| hot_gril wrote:
| Interesting 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_.
| deaddodo wrote:
| Yes, _Americans_ invented populace relocation (and the
| abuses that come with it). Nice to know the Roman Empire
| had a time machine to pull a major component of their
| imperial edict from.
|
| But let's pretend your warped view of history is
| reality...that happened 100 years earlier. If Europeans
| are so enlightened atop those tall horses, maybe don't do
| it again and 10x worse?
|
| In addition, I wasn't referring to the Holocaust...but
| the entire continent's shared sick desire to kill
| themselves off for 10km of border movement or literal
| dreams of world conquest.
| hot_gril wrote:
| This wouldn't surprise me, but I can't find it. I'm
| seeing some authors drawing comparisons, but haven't
| found Hitler or his party actually mentioning Native
| Americans. There are explicit references to Turkey, with
| Hitler mentioning the Armenian Genocide (as justification
| for invading Poland) and calling Ataturk a "shining
| star," along with the Nazi papers obsessing over his
| nationalist policies.
| hot_gril wrote:
| Ok I'm going to make this even darker: The metric system
| sucks for non-scientific usage, especially using Celsius
| for room or weather temps. Idk why Europeans (and other
| continents) insist on using something with such low
| granularity and weird usable ranges. 0F = prob not going
| outside, 100F = close to highest temp you'll see all
| year, 56C = highest outdoor temperature ever on Earth. In
| the 70s (F) = warmish weather, in the 60s = coolish
| weather, in the 20s (C) = either cool or hot. Digital
| thermostats add 0.5 increments if you set them to C mode,
| lol. Meanwhile KPH is too granular, while 0-100MPH is all
| you need for cars outside of racing. Divisibility into
| meters etc is pointless, cause it's not like I need to
| compare a road trip length to the height of a person.
|
| No surprise that basing your units on the physical
| properties of water doesn't give you very human-friendly
| results. Their only good unit is kilograms/grams. Edit:
| actually not even that.
| riversflow wrote:
| Meh, I don't even thing grams are very good.
|
| Pounds have a nice granularity for every day stuff: a 3
| pound laptop and a 2 pound laptop are significantly
| different, but both are "about a kilo".
|
| On the other end, a gram is such a small amount that I
| can only perceive it in multiples, whereas I have a
| pretty good idea of how much an ounce is.
| hot_gril wrote:
| Actually yeah, I remember realizing the same thing a
| while back. 1 pound difference is about what I can
| perceive. Same with 1@F difference.
| Dylan16807 wrote:
| A laptop that's a pound and a half is also very
| different.
|
| But oh, if you're willing to say "and a half" you might
| as well be willing to say .7 kilo.
|
| There's no real overall advantage, you just picked a
| couple very specific numbers. You can always pick very
| specific numbers to make any system look better/worse.
| mulmen wrote:
| Inventor 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]
| chris_va wrote:
| ... the infrastructure is high voltage 3-phase, same as
| EU.
|
| Also, stone tools are easier to replace :P
| saiya-jin wrote:
| Its 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 wrote:
| This 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 wrote:
| The 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.
| kelnos wrote:
| > _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.
| Gravityloss wrote:
| Since 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-3...
| malermeister wrote:
| I 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 wrote:
| How esle is the home going to get renovation work and
| upkeep done?
| hinkley wrote:
| The 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.
| cptcobalt wrote:
| In 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 wrote:
| That'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 wrote:
| No? 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 wrote:
| What kinds of mistakes are harmless at 120V @ 100A vs
| 400V @ 30A?
| rootusrootus wrote:
| Touching 120V with dry skin is nearly always harmless.
| 240V is considerably more exciting.
| b3orn wrote:
| Wait, 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?
| kelnos wrote:
| Not sure if there's an additional certification, but it
| would not surprise me at all that an electrician here
| would not want to work on a home with an unusual setup
| that they're not particularly familiar with.
| chinchilla2020 wrote:
| There isn't. But residential electricians are
| specialists. Then there are commercial and industrial
| ones, etc, etc.
| CapitalistCartr wrote:
| Electricians specialize. Resi guys do residential and
| rarely to never handle 3 phase. I do commercial and light
| industrial because heavy industry isn't around here and I
| despise doing resi work. Three phase is usually run
| everywhere by the power co and a transformer (pole pig)
| converts to single phase near the residence.
| Blackthorn wrote:
| Maybe 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.
| RedShift1 wrote:
| In 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 wrote:
| Not always - I live in the countryside in the UK and we
| seem to have single phase sadly.
| youngtaff wrote:
| Tends 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
| gambiting wrote:
| Nearly everywhere in UK has only a single phase supply,
| it's how the grid in this country is designed.
| Blackthorn wrote:
| You 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 wrote:
| You can get it if you're willing to pay for it, but you
| may not like the quoted price.
| coding123 wrote:
| In CA it's just a matter of checking a box, then they put
| a transformer on the PG&E pole to match your voltage reqs
| - the wire to your pole is $90. The transformer can run
| in the thousands probably up to 10k. Of course, if your
| area can't handle the voltage * amperage requested, they
| may deny it or ask for about 10k per new pole to install
| in the ground.
|
| That said you just pay that once, after that you have
| your rate.
|
| A lot of people have odd power requirements - but usually
| not residences. Farms typically get 400V for greenhouse
| fans, for example.
| bob1029 wrote:
| If 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 wrote:
| I 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.
| coding123 wrote:
| And of course, an alternatives is to have a battery bank
| as well with inverters - which means you can get your
| amps - but only if you're not running 24/7. You'd have to
| let the grid (or solar) charge you up.
| Blackthorn wrote:
| My own shop uses:
| https://www.phasetechnologies.com/products/phase-
| converters/...
|
| It's nice because there's no motor to worry about
| maintaining and the machines can run at full power.
| Blackthorn wrote:
| Haha, 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 wrote:
| Have 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.
| hajile wrote:
| 400v 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 wrote:
| I read it as 400v coming into the house, not coming out of
| outlets... Like 220v is coming into the house in the US.
| [deleted]
| ohgodplsno wrote:
| You 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 wrote:
| EU 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.
| z2 wrote:
| The Swiss and UK plugs and receptacles are awesome
| because they have plastic buffers in the plug's prongs
| and/or receptacle that make it hard to ever be able to
| touch live metal prongs in a plug that's between 0 and
| 100% plugged in. Schuko looks pretty safe too and that
| standard is from almost 100 years ago! I consider myself
| careful, but have had a metallic cover and a pen fall
| onto North American plugs that were partially exposed
| (thus shorting hot with neutral). Both times the outlet
| had tamper resistant shutters which did nothing to
| prevent ensuing fireworks.
| tails4e wrote:
| Yes the UK plug design is the best I've seen. Mandatory
| 3rd pin to open the shutters, insulated prongs until they
| are well disconnected, and very solid fit. More often
| than not I see plugs half falling out of US sockets, with
| live and exposed terminals. Thankfully it is only 110v,
| but still a fire hazard
| rodgerd wrote:
| The UK plug is the gold standard, and for me it's one of
| those things that would have been great if they concepts
| had become the norm.
| lazide wrote:
| Too bad it weighs so much :s
|
| Also, stepping on one in the dark is a... life changing
| experience! Definitely pretty solid though.
| codedokode wrote:
| Will you get an electric shock from sticking a fork
| across pins? I thought that the fork would short the
| curcuit. More probable scenario is that one can easy
| stick a finger between pins when plugging or unplugging a
| device.
|
| That is why the voltage should be lowered to 70 Volts.
| housemusicfan wrote:
| > _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. _
|
| Literally _every single thing_ you 've asserted is
| categorically false.
|
| Earth pins have been required on outlets for nearly 50
| years at this point. US outlets are also polarized, which
| Europlugs are not.
|
| Shutters on outlets have been mandatory in residences and
| medical facilities for well over a decade.
|
| The cable gauge is sized for the current and ambient
| temperature.
|
| GFCI outlets are required nearly everywhere there is
| water, damp conditions (such as basements), and power
| tools used (such as garages and outdoors) because tools
| are most likely to have frayed and poorly repaired cords.
| Additionally all bedrooms and living spaces now require
| arc fault protection as a leading cause of fires is due
| to frayed lamp cords.
|
| Europe still leads the world when it comes to smoking in
| bed as being a leading cause of house fires so I would
| not cast stones in glass houses.
| crooked-v wrote:
| > Shutters on outlets have been mandatory in residences
|
| The only shutters on outlets in any US homes I've ever
| lived in have been... ones I put in myself.
| chinchilla2020 wrote:
| > rarely if ever had an earth pin
|
| False
|
| > GFCI outlets are a miracle to find
|
| False
|
| I don't know where some of these people come from on
| hackernews.
| jumpkick wrote:
| Are you saying that US homes "rarely, if ever" have
| grounded receptacles? That's not correct. All
| construction since the late 50s or early 60s require
| grounded receptacles.
| WheatMillington wrote:
| And it's a good thing that 110v is safer because American
| electrical safety standards are appallingly bad.
| tails4e wrote:
| And given the US outlet design, I imagine people do come
| into contact with 110v quite frequently!
| kelnos wrote:
| The 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-...
| SSLy wrote:
| I live in a house built somwhere between 1900 and 1930, and
| it's powered by 3 phases. Since deep commie era.
| danieldk wrote:
| We 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 wrote:
| Long 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.
| quickthrowman wrote:
| Here 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 wrote:
| Why are AC units measured in weight?
| kens wrote:
| It'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 wrote:
| I thought the conversion was exact.
|
| The latent heat of fusion of 1 pound of water at 0degC is
| 144 BTU. 144 BTU/lb * 2000 lb/ton / 24 hr is 12000 BTU/hr
| per ton exactly.
| kens wrote:
| No, the latent heat of fusion is 143.6 BTU/pound, not
| 144. It's just a coincidence that the energy to raise
| water one degF / the energy to melt ice is almost 144.
| nvy wrote:
| Good grief what an obtuse system of units.
| gottorf wrote:
| Like many customary units, the ton (of cooling) is tied
| to historical accidents and I dare say is easier to
| imagine for a layperson; one could visualize the coolness
| rushing off a cubic-meter block of ice in a room, and how
| quickly it would melt depending on the temperature. 12000
| BTUs, in the other hand, is not as intuitive (and the BTU
| itself is a customary unit, which is the amount of energy
| required to raise the temperature of one pound of water
| by one degree Fahrenheit).
|
| And further, I guess there's just not much to be gained
| by going metric and saying "14 kilowatt AC unit" vs.
| "4-ton AC unit".
| Symbiote wrote:
| Since electricity is metered in kilowatt hours, it's much
| easier to see the running costs of a device with a power
| given in that unit.
| Kirby64 wrote:
| When picking an AC unit, running cost is not the primary
| concern: sizing is the primary concern. If you pick too
| large or small of a unit you will have issues. Too small
| won't be able to cool, too large generally won't be able
| to bring humidity down (outside of the newer inverter
| units that can run slower for longer).
|
| Tons (or, BTUs of cooling) makes more sense, because the
| efficiency for a given cooling amount is variable.
|
| For efficiency, we have efficiency ratings in the
| SEER/SEER2 ratings.
| Dylan16807 wrote:
| Kilowatts are ambiguous between amount of cooling and
| amount of electricity used.
| sammorrowdrums wrote:
| Good 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.
| lol768 wrote:
| > Really all modern residential connections in Europe are
| 400V three phase electric power
|
| Not the case in the UK.
| gambiting wrote:
| UK 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 wrote:
| UK scored a massive own goal and are no longer part of
| Europe ;)
| gambiting wrote:
| I assume that's tongue in cheek, but EU and Europe are
| two different entities - UK is still very much in Europe.
| Kirby64 wrote:
| How 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.
| bell-cot wrote:
| > ...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...
|
| Vs. checking a couple commodity pricing web sites - copper
| is currently ~$3.85 per pound.
|
| I really doubt the motor of any "residential" HVAC unit is
| heavy enough for that "hundreds of dollars" to actually pan
| out...
| Kirby64 wrote:
| I'm referring to the cost of the wiring, not raw copper
| stock price. Also, I mean the cost of the wire from the
| breaker panel to the HVAC unit. On average, I'd assume
| that the wire run is at least 50 feet. 100 feet wouldn't
| be unusual. 100 feet of single-wire 10 gauge THHN (enough
| to run most HVAC units here) would be ~$60. That also
| doesn't include any additional cost by upsizing certain
| things (conduit) that may add.
|
| To note, as mentioned, copper is not the only cost here.
| You also need another pole to your breaker, which adds
| cost. Plus busbar upgrades. And more.
| timc3 wrote:
| 3 phases is cheaper than single line for delivering a
| houses power. You can get away with 3 smaller cables than
| the larger cables needed for 110V or 230V low voltage
| single phase at a particular amperage.
|
| The cost of termination of 3 phases is insignificant
| compared to the cost of the rest of an electrical system
| in a modern home.
|
| It's the better system.
| [deleted]
| dijit wrote:
| > How many residential appliances benefit from three phase
|
| I know of at least one, but I am ignorant of many other
| things and this just comes from my understanding of AC
| motors but: Any directly connected AC fan will have
| enormous benefits in terms of performance and efficiency
| with three phase.
| Kirby64 wrote:
| Low current devices such as AC ceiling fans use so little
| current that the wire gauge is largely based on the
| minimum sizing for code standards. At least in the US,
| you can't put anything smaller than 14 gauge (AWG) in
| walls. Maybe in Europe they allow much smaller gauge, in
| which case maybe it makes sense... but usually there are
| minimum requirements for wiring since it becomes a
| structural issue (i.e., too thin of wire will break
| easily when pulled).
| quickthrowman wrote:
| There is no benefit to performance or efficiency with a
| single-phase motor vs a three-phase motor.
|
| Controlling the motor with a VFD is how you increase the
| efficiency and performance of a three-phase motor, simply
| being a three-phase motor provides no efficiency benefit
| other than you can use slightly smaller conductors to
| power the motor.
| brianwawok wrote:
| Why are large industrial motors three-phase? I almost
| always see large industry getting three-phase, which I
| assumed either gave more power or more efficiency.
| thsksbd wrote:
| It has nothing to do with efficiency (do the math on the
| conductor gauge and it all mostly cancels out) or power
| (idem) but the types of motors used (squirrel cage I
| believe).
|
| The problem is getting the motor to start spinning. You
| cant start all motors on just one or two phases. And if a
| motor isn't spinning, it's essentially a short.
| quickthrowman wrote:
| Basically what the sibling comment said, it's easier to
| start a three-phase motor, and a three-phase motor will
| also run more smoothly as it is powered by 3 sine waves
| 120 degrees out of phase with each other which provides
| constant power; versus a single-phase motor being powered
| by a single sine wave that outputs no power at the middle
| of the sine wave with two power peaks, which doesn't run
| as smoothly as three-phase power with no points of zero
| power output.
| [deleted]
| japanuspus wrote:
| I read this comment as implicitly assuming two phases to
| require less copper than three. In reality, the total
| copper cross-section needed to transfer power in a multi-
| phase system _decreases_ with increased number of
| independently wired phases (all else being equal).
| [deleted]
| loandbehold wrote:
| Transmitting same amount of power at higher voltage
| requires LESS copper.
| kelnos wrote:
| But you need an extra conductor, no? Doesn't that make up
| for the reduced amount of copper in each one?
| nullc wrote:
| For 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.
| [deleted]
| user2342 wrote:
| > How many residential appliances benefit from three phase,
| and is the benefit outweighed by the additional cost of
| more copper for the additional wires?
|
| Three phase wiring is so ubiquitous here, there is nearly
| no additional cost.
| Kirby64 wrote:
| You can't just say there's no cost because you don't see
| it. You don't have the option, so of course there's no
| way to tell price differentiation. I'm talking purely of
| raw material cost though. By adding a 3rd load conductor,
| you inherently add wiring cost and complexity, which
| should result in cost to the consumer.
|
| It may be offset, as others point out, by power delivered
| being higher (and thus, wire gauge can go down) when
| running 3 phase... however that will largely depend on
| the load.
| bluGill wrote:
| Most people have so few things in their house that would
| benefit from 3 phase that the cost isn't worth it. That
| extra wire isn't cheap, even if you downsize them all you
| still pay more. And as others have pointed out modern
| motors are (slowly) switching to using a VFD to generate
| 3 phase so there is even less need (in fact in industry a
| lot of equipment is switching to a VFD even though 3
| phase is wired to the machine)
| timc3 wrote:
| The cost is insignificant.
|
| I have monitoring on all the phases on my house (in
| Sweden) and I can charge two electric cars, run the
| heating in winter, run the washer and drier and cook with
| two ovens a microwave and the induction hob at the same
| time and everything just works.
|
| Things on three phase in my home: swimming pool, sauna,
| induction hob, electric car chargers, heating system and
| I have sockets to plug-in welding and other power hungry
| equipment. The rest is split on the phases. I can't
| remember whether my solar system supplies on three phases
| or not but I think it does.
| jonhohle wrote:
| Others have made the comment about lower current
| requirements at high voltage, but from a maintenance
| perspective, that $20 capacitor is a common failure part.
| Calling an HVAC repair company to diagnosis, parts, and
| labor it costs around $200 for anyone not electrically
| minded. Over the life of an AC unit, starter/run caps might
| have to replaced twice.
|
| Even if an extra conductor in the line was a few hundred
| dollars, I'd rather have one less common failure point. In
| AZ AC is effectively required in the summer. AC outages are
| similar to winter furnace outages in northern areas. I have
| extra caps ready to deploy (we lose a cap about every 3
| years across multiple units) but have never needed to
| unexpectedly replace copper.
| jrockway wrote:
| Don't more modern AC units use VFDs that can run the
| compressor at arbitrary speeds, which is an improvement
| over both fixed 3 phase power and a starter capacitor?
| Maybe this tech hasn't made it into the house-sized units
| yet, though.
| lfowles wrote:
| It was only present on the high end when we were
| replacing our system in 2021.
| kelnos wrote:
| Unfortunately these more modern units are still stupid
| expensive (in the US) compared to the older style.
| Unclear why; probably some sort of shenanigans with the
| HVAC manufacturing companies.
| amluto wrote:
| Little variable-speed units sold as ductless minisplits
| are fairly inexpensive in the US. They're especially
| reasonable if you actually use them in a ductless
| configuration, because you don't have to install ducts.
|
| The fact that they might have a higher list price than a
| conventional single-speed outdoor unit and indoor
| evaporator coil is a red herring, as the conventional
| units can't do anything on their own, and they need a
| furnace and a fan added to be useful.
| mindslight wrote:
| VFDs / "inverters" are happier on 3 phase as well,
| because the input rectifier caps can be much smaller.
| Whereas with single phase they have to be large enough to
| store energy for riding out the zero crossings of low
| power delivery.
|
| This whole thread is like that Dewey Cox bit. "But three
| phase surely must use more copper, no?" "Actually it uses
| less". Split phase is really just a great demonstration
| of institutional momentum.
| lizknope wrote:
| I just replaced one of my two HVAC units with a variable
| speed compressor. It cost a lot more than the single or 2
| stage units but it is more comfortable, uses less
| electricity, and runs at "low" to dehumidify longer.
| Kirby64 wrote:
| My point isn't that the single individual wire to your
| HVAC is $100 vs. a $20 cap, though. There is likely
| hundreds or thousands of dollars of additional
| infrastructure needed to handle 3-phase input to a house.
| You have breakers, busbars, the transformer into the
| house is different, and on and on.
|
| I agree that less failure points is nice, however you
| have to consider the tradeoff. Is it worth $100?
| Probably. What about $1000? $2000? If it's $2000, why not
| just get a more efficient inverter based one, which
| doesn't have a starter cap in the first place?
| hnuser123456 wrote:
| Just had to have my apartment's AC capacitor replaced
| last week.
| rekoil wrote:
| > How many residential appliances benefit from three phase
|
| Induction hobs, saunas, EV chargers, to name some.
|
| > and is the benefit outweighed by the additional cost of
| more copper for the additional wires?
|
| Additional cost? You don't run that many 3-phase circuits,
| so the cost is negligible, and your 110V circuits require
| substantially higher current than ours (meaning thicker
| wires) so if anything I'd guess the cost for wiring a US
| home is on average higher than a European home.
| Mvandenbergh wrote:
| In many places (but not the US because of thermostat
| standards) HVAC systems are now typically inverter driven
| as well so that does remove some of the advantages of
| three-phase since any individual load is single-phase
| anyway.
| briHass wrote:
| Many HVAC systems in the US also use inverter compressors
| now. The efficient units (which includes most minisplits)
| are inverter. The efficiency requirements of the recent
| government subsidy program pretty much requires an
| inverter.
| gambiting wrote:
| Well, here in UK nearly all residential properties have
| only a single phase supply - it can actually be really
| limiting nowadays. Some older properties are only wired for
| 60amp draw at 220V, meaning you can really only have an
| electric shower and an oven on at the same time and that's
| it, you've gone over the limit. People are finding it more
| and more as electric cars are getting popular and turns out
| fitting a 32amp(7.2kW) charger on a single phase 60 or even
| 80amp supply is sometimes not feasible depending on what
| else you have in your house already. Continental setup is
| far superior to what we have here for this reason.
| rekoil wrote:
| > meaning you can really only have an electric shower and
| an oven on at the same time and that's it, you've gone
| over the limit
|
| What's the deal with your electric showers anyway? Surely
| it's more efficient to heat in a central location and
| distribute both a cold and a hot water circuit through
| the building...
|
| Probably talking out of my ass, it's just so weird and I
| haven't seen it anywhere other than in the UK.
| muxator wrote:
| > 60amp draw at 220V
|
| You are very luky! The standard installed power for
| residential use in Italy is 220 V, 3.3 kW.
|
| My apartment runs on it. I have a small heat pump
| reservoir for hot water, AC, induction coils for cooking.
| I think having to cope with this objective limitation in
| installed power really pushed me to look for maximum
| efficiency, to the point that I could have gone to 4.5
| kW, but it ended up being not needed.
|
| Nowadays, the idea of heating water to >50 degC via Joule
| effect in real time seems a bit inefficient to me.
| Faaak wrote:
| On the contrary, more phases = less copper.
|
| Example of appliances: HVAC, induction heaters, boilers,
| car chargers, solar panels inverters, ...
| wyager wrote:
| Three phase and high voltage are both more copper-
| efficient.
| sidewndr46 wrote:
| inverter technology is always an induction motor. No one
| runs an inverter to run a universal motor.
| dreamcompiler wrote:
| Brushless DC motors are always driven by inverters. They
| aren't usually _sinusoidal_ inverters, and these things
| are more accurately called digital electronic pulse
| modulators, but they 're often advertised as "inverter-
| controlled."
| webmobdev wrote:
| Three-phase power supply for residential use is common even
| in India.
| dusted wrote:
| In Denmark, most homes have 3 phases of 240 volts, along with
| neutral. (and protective ground, of course)
|
| More power in less copper. Most items do fine with 240 volts,
| but high-power items like ovens and electric cars can use two
| or three. Also, we have the CEE 5P plugs, which look awesome
| and allow you to draw a lot of juice from a single point.
| Mvandenbergh wrote:
| The US also uses a different primary network configuration,
| typically running a three-phase network as main primary with
| single phase primary laterals. The pole-mount single-phase
| transformers then turn this single-phase into split-phase LV
| for consumer use. One consequence of this is that adding three-
| phase to a property that doesn't have it already is really hard
| - you need to upgrade the LV service connection, the
| transformer, and the MV lateral (since the MV lateral is only a
| single phase). Compare that to the European system which has
| three-phase distribution transformers and then runs three-phase
| LV past every property. In some places like Germany, the
| standard is to provide three-phase to every property, in others
| like the UK, standard is single phase service connection but...
| it's easy to add three phase since the other two phases are
| only a few metres away, I understand the Dutch standard is to
| run all three phases to the property but only connect as a
| standard (you have to pay for the upgrade).
|
| I think in both cases, for urban and suburban areas it is
| standard to run the MV feeder as a normally open ring so that
| in case of a fault in the primary, parts of the system can be
| run from the other end of the ring by remotely operated
| automatic breakers. What I don't know is whether US systems do
| that at the level of the main primary only or also on the
| laterals.
| dehrmann wrote:
| Could I run a standard computer PSU of 220V split-phase?
| zeroonetwothree wrote:
| At current rates of ballooning power requirements we will
| soon have to
| mrguyorama wrote:
| American circuits are designed to support a constant 15amp
| load, meaning you get 1500 ish watts. One 4090 overclocked
| and one high end Intel CPU overclocked, plus the cooling
| for all that, plus other parts, gets you uncomfortably
| close to that.
|
| My hope is that this limit forces the computer industry to
| put at least one cycle into actual efficiency instead of
| just promising a node shrink will magically fix things,
| since we only have a few of those left really.
|
| I shouldn't need to run a damn space heater to play a
| stupid video game. At this rate, you have to think about
| how much video game you plan to play in your electricity
| budget!
| hot_gril wrote:
| Most video games don't require high-end gaming PCs,
| though.
| hajile wrote:
| You can increase wire size a little and run 20 amps
| without much trouble.
| sleepybrett wrote:
| Yes but most of your house's power outlets are sitting
| behind a 15amp fuse.
| TylerE wrote:
| Every computer power supply I've seen in the last 10 years or
| so is basically rated for input as something like '100-250v,
| 50-60hz. That way they work on virtually any power grid
| anywhere in the world, it's just a matter of having the right
| female IEC to male <local whatever> power cable.
| Gibbon1 wrote:
| White paper I read 20-25 years ago described how those tend
| to work. Larger power supplies are required to be power
| factor corrected. They need to draw sinusoidal power in
| phase with the voltage. To do that they need a power factor
| correction front end. In the design the paper described
| what happens is 120VC gets rectified and stepped up to
| 240DC. Which then feeds a main DC/DC step down inverter.
|
| I think the advantage of stepping up is the filter
| capacitors are cheaper for the higher voltage. I think
| because they handle half the current.
| mrguyorama wrote:
| Cheaper and older power supplies typically have a switch to
| change the input voltage. DO NOT attempt to plug in and
| turn on a power supply set to 110v to a 240 volt socket.
| nullc wrote:
| Yep, most of them are a few percent more efficient at 240v
| too and have higher maximum power output... I run all my
| always-on computers that way.
|
| _Generally_ anything that has an IEC power connector will
| support running at 240v (but beware, you may need to flip a
| switch).
| ianburrell wrote:
| Most power supplies do 100-240V so they can be used in
| multiple countries. You might be able to find cable to
| connect it to 240V plug, or could wire one up. But there
| would be no advantage to using 240V.
|
| The only advantage for 240V is higher power. All desktop PSUs
| top out at 1800W because of the 120V 15A limit. There are
| server PSU that have higher power limits that would need to
| use 240V to reach the higher limit.
| lokar wrote:
| Most switching power supplies won't care
| 2143 wrote:
| > I have heard a three phase residential connection is common
| in some parts of Germany
|
| Over here (large country in South Asia) it's three phase by
| default.
|
| You can get single phase upon request, provided it's a really
| really small house, shop etc.
| elzbardico wrote:
| EDIT: I stand corrected by the comments below. Readers Ignore
| most of what I said on this comment. I was mistaken.
|
| --------------------------------------
|
| You have some misunderstandings in your comment.
|
| Unless it is a very old construction or a smaller home, houses
| in the US as well as most of americas are provided with one or
| more phases derived from the secondary of a step-down
| transformer in Y configuration (3-phase, 1-neutral => 4 wires).
|
| So, for a small apartment, maybe you'll get a single phase wire
| plus the neutral, or more commonly 2-phase wires plus neutral,
| up to the full 3 phase wires plus neutral.
|
| The phases are usually 220V between then and 120 between any
| individual phase and the neutral connector.
|
| Europeans don't have this convenience because the step-down
| transformers give homes 3 phases in a delta configuration (so,
| 3 phase wires, no neutral wire), so, they only have the 220V
| between any two-phases.
|
| Also, split and wall ar-conditioning systems are almost
| universally bi-polar with a capacitor, in Europe, Asia, or the
| Americas. As well as most refrigerators, freezers and other
| similar appliances. In the past we used to have driers that
| would be multi-polar, but it was never very common.
|
| It is more usual to have tri-phase motors in bigger motors,
| like those used in central AC units. And HVAC systems in the US
| accordingly will usually require an upgrade if your home is not
| wired with 3-phase plus neutral, unless it is a small HVAC.
| Electrical vehicle charges also usually require 3-phase.
|
| People are confusing what they have the electric outlets inside
| their homes with what gets from the street into the
| distribution panel in the house. Most power outlets inside a
| house are bi-polar connectors (so, in europe, they can only be
| 220 phase-to-phase, and in the US and most of the American
| continent, they can be either 220 phase-to-phase or 110 V
| phase-to-neutral. The third connector in a domestic outlet is
| usually the ground, not another phase or the neutral.
|
| The three-phases are usually split between different circuits
| at home, trying to ensure that the load is somewhat evenly
| split, but at the outlets, you'll have either phase-phase, or
| phase-neutral, and this is the same in Europe or America, but
| the americans have the flexibility to have phase-neutral dipole
| with half the voltage that europeans don't have.
|
| Regarding having smaller step down transformers close to homes
| instead of a single giant unit, we need to remember that
| keeping the low-tension wires short is more efficient, and this
| is achieved by having the transformers closer to consumers,
| instead of having a giant transformer distant from the
| consumers.
|
| I am not an American, and I know that a lot of things in
| America could be more efficient, but power distribution to
| residences is probably not something were europe have an edge
| over the US.
| [deleted]
| sbradford26 wrote:
| So your first statement is correct for apartments and condos.
| Typically 3 phase comes into the building then each unit gets
| 2 phases and a neutral ran to them. This actually works out
| to 208V phase to phase but phase to neutral is still 120v.
| Appliances like cooktops and ovens are definitely less power
| when ran off of 208v. For single family homes you only get a
| single phase, a center tapped transformer steps down the
| voltage to 240V leg to leg so coming into the house is two
| legs from the transformer and the center tap which is your
| neutral. Some really large houses sometimes get 3 phase but
| that is very rare. Usually large houses will just bump to 400
| amp service.
| LeifCarrotson wrote:
| > Unless it is a very old construction or a smaller home,
| houses in the US as well as most of americas are provided
| with multiple phases in Y configuration (3-phase, 4 wires,
| one neutral).
|
| > So, for a small apartment, maybe you'll get a single phase
| wire plus the neutral, or more commonly 2-phase wires plus
| neutral, up to the full 3 phase wires plus neutral.
|
| > The phases are usually 220V between then and 120 between
| any individual phase and the neutral connector.
|
| I am an American - an electrical engineer in the Midwest -
| and I was on roofs last week after a tornado came through our
| town, working with the distribution panels. What you said is
| not correct. Homes get 240/120 nominal line voltage, or
| 220/110V at the load, 180 degrees out of phase, plus a
| neutral.
|
| That is not the same as two phases plus the center conductor
| of 3-phase Y.
|
| In industrial facilities, it's reasonably common 208V 3-phase
| in a Y configuration, with three wires each 120 degrees out
| of phase with each other. This is typically used for lighting
| circuits, because it's 120 phase to ground and can use
| commodity bulbs and ballasts. More commonly, machines will
| run off 480V 3-phase, which is 277 phase-to-ground.
| elzbardico wrote:
| I stand corrected and added a disclaimer in my original
| comment. Thanks for teaching me something I assumed
| incorrectly.
| coding123 wrote:
| Just for knowledge sake: you are correct that there are 4
| wires: 1 - hot 1 120 v 2 - hot
| 2 120 v 3 - neutral 4 - ground
|
| The hot 1 and 2 are 180 degrees out of phase with each
| other which is why 240v appliances can consider having
| those 2 wires (and at least the neutral) to be a 240v
| appliance.
|
| And to be more pedantic about it, the ground is not
| provided not by the power company but the ground. I have
| 3 lines coming from the grid to my pole, line 1, 2 and
| the neutral that is created by the transformer. The
| ground comes from my ground - a long copper wire that
| goes a few feet down and back up. All ground connections
| in the (future) house will go there. Ground is also
| bonded with neutral at the box on my pole.
| MichaelZuo wrote:
| Same in Canada, though with 600V 3-phase instead of 480V,
| mostly.
| no-reply wrote:
| Three phase residential connection is also common in India (at
| least some bigger cities).
| amluto wrote:
| How many residential devices actually ought to contain a three-
| phase motor running at fixed frequency? (And I mean now, in
| 2023, not in 1990.)
|
| I can think of three, sort of:
|
| 1. A well pump, pumping from a high-producing well, into a tank
| or pond at the surface, where the pump is sized to efficiently
| pump somewhat less than the well's production.
|
| 2. A pool or pond pump which, by some miracle, has been
| correctly sized for the system, and which, by some other
| miracle, is more appropriate in the application in question
| than an Intelliflo VSF or similar pump.
|
| 3. HVAC fans. But these are usually pretty small, and better
| systems usually use ECM motors.
| Corrado wrote:
| There are tons of people who have garages with table saws,
| air compressors, etc. that would benefit from 3 phase power.
| ajross wrote:
| I think that's overselling. I mean, sure, 3 phase is better
| for motors and you can get more power a little more
| efficiently and with less vibration to deal with in the
| mechanical design. And that's valuable. But come on, US
| workshop afficionados are doing just fine. No one is crying
| in their shop wishing for the blissful experience of a
| Danish band saw or whatever. It's better. It's not _that
| much_ better.
|
| What actually wins this fight is on the other side. A two-
| connector polarized NEMA 1-15 plug is a tiny, convenient,
| easy to use form factor that will still deliver 1400W. The
| experience of a normal consumer plugging in their normal
| junk in the US is just plain superior to the poor folks
| across the oceans charging their devices with BS1363
| connectors that are _almost bigger than the phones_. And
| don 't even get me started on Europlug.
| housemusicfan wrote:
| BS1363 are comically oversized because they contain
| internal fuses, due in part to the strange ring main
| design, itself a vestige of WWII copper shortages.
| pmyteh wrote:
| BS1363 plugs are joyfully oversized, yes (and make
| excellent caltrops if dropped) but they are in other ways
| _excellently_ engineered. Inherently polarised, fuses to
| protect the appliance wiring[0], socket shutters that
| open on the earth pin only to prevent vigorous insertion
| of metal by children, sleeved conductors to avoid shock
| when partially inserted, essentially unbendable...
|
| Plus, I will fight anyone who suggests that 1400W is
| enough for a decent kettle ;-)
|
| [0] Admittedly this was mostly included to offset the
| idiosyncrasies of final ring circuit wiring, but it's
| still better than just a big breaker.
| shrx wrote:
| Every time I try to charge something from a US socket the
| charger cable will frequently fall out of the socket due
| to poor design tolerances. Never an issue with EU
| sockets.
| liquidgecka wrote:
| I have all three of these and absolutely none of them contain
| (or will contain at any point) a three phase motor. All three
| of these use variable speed motors in my house. I suspect
| even more will moving forward as well. So honestly three
| phase is pointless as I just need "power" to drive the
| variable speed controller system. My hottub has fixed speed
| 220 pumps but its old. I suspect newer systems would be
| moving to variable speed as well.
|
| I think your pretty spot on that most people do not need 3
| phase, even in the limited cases you mentioned. =)
| dfox wrote:
| The split phase arrangement comes from Edison's DC systems. For
| large installations they found out that the losses were
| unacceptable and solved thet by running the lighting on 220V
| with sets of two 110V bulbs in series, usually combined with
| some somewhat funky wiring scheme in order to even more reduce
| the required wiring cross-section (it is somewhat reminiscent
| of later British ring mains construction and strikingly similar
| to various arrangements for powering long LED strips). This is
| also the reason why it is somewhat common for the US commercial
| lighting to use 220V.
|
| Three phase for residental connection is pretty much a standard
| everywhere with 230/400V system. Only small flats and really
| small houses get single phase. This is because the 230/400V
| output of the larger distribution transformer is inherently
| threephase and this gets distributed to essentially all the
| points of connection and the only reason why there are single
| phase residental connection is that they are slightly cheaper
| (both in terms of fixed monthly payment for capacity and in
| terms of initial installation costs). While in US the input to
| the typical residental pole/pedestal mounted local distribution
| transformer is already single phase, so you cannot really get
| three phases without running additional wires to the substation
| (and probably also having you own dedicated distribution
| transformer) and thus in a residantal area you are simply stuck
| with split-phase.
| sokoloff wrote:
| > solved thet by running the lighting on 220V with sets of
| two 110V bulbs in series
|
| A related tip is to build a "dim bulb tester" to help you
| diagnose short circuits on mains-powered equipment. I have a
| traditional incandescent lightbulb in a porcelain socket
| wired in series with an outlet (and a switch). A non-shorted
| load will tend to work pretty well as the cold/cool
| incandescent bulb is fairly low resistance in series with the
| load. A shorted load will light up the light bulb brightly
| but not trip any breakers, allowing the opportunity to do
| some troubleshooting on the bench.
|
| I've also used this concept several times to find short
| circuits in house wiring. Put the dim bulb tester in series
| with the circuit that's shorted and then, using a non-contact
| voltage tester, find where the measurement on the NCVT
| changes. That's likely where your short is.
|
| In building such a device, you're on your own liability-wise;
| please don't be dumb.
| mindslight wrote:
| When I was a kid, I (ab)used this trick by wiring around a
| dozen 100 watt bulbs in parallel, between the line and a
| "probe". It was great fun for zapping whatever I wanted,
| writing stuff on metal, etc. In retrospect the biggest
| safety issue I missed was the light from the arc.
| MrBuddyCasino wrote:
| Another thing Americans miss out on - the "boost" function on
| modern induction stoves. Since the oven usually gets one
| phase and the cooking fields get two dedicated phases of the
| 400V lines, you can use "boost" to steal power from the other
| phase. Water boils even faster than in a tea kettle!
| Kirby64 wrote:
| What do you mean? Comparing a UK Bosch induction hob with a
| US one, they both seem to offer roughly 2.5kW of power in
| normal mode, and both offers a "boost" functionality that
| boosts the output temporarily to 3.6kW.
|
| Stove outlets can handle 12kW in the US... So there's
| plenty of power to go around. Built in outlets can go even
| higher, with 240V/60A being somewhat common for larger
| appliances.
| MrBuddyCasino wrote:
| It is hard to find numbers, but combining phases is
| definitely how it works for some models, eg Miele
| PowerFlex uses "booster output of up to 7.4 kW" [0]. This
| is why you can only use it for one field.
|
| > Stove outlets can handle 12kW
|
| wasn't aware, in that case I was wrong, good for them
|
| [0] https://www.miele.co.th/domestic/1512.htm?&&&info=200
| 004302-...
| andersa wrote:
| Sure would be nice to have some kind of hyper boost
| setting. There's a 3 phase connection, so why don't they
| use it? Time to heat that one pot of water with 11 kW.
| [deleted]
| Ekaros wrote:
| Having 3 different inducting circuits would be hard to
| fit and make less even heating distribution. Also I think
| they would induct to each other. Also 11 kW could be
| dangerous with empty containers that is quite a bit of
| power. Like resistive heaters get red hot at lower power.
| andersa wrote:
| There are actually some stoves out there that can use two
| phases for one large pot, reaching 7.2kW. For example,
| Miele stoves with the "PowerFlex" feature do this (that
| is quite the big brain name given the context).
|
| Since it is possible to do for two phases, why wouldn't
| it also work for 3? More power!
| dtgriscom wrote:
| More power! https://www.youtube.com/watch?v=kBNPAJLhKZ4
| sbradford26 wrote:
| American induction cooktops also have boost functionality.
| All boost does is temporarily increases the power output
| usually at the expense of other elements. Power isn't
| "stolen" from other phases. Usually the reason why the
| cooktop cannot be in boost mode the entire time is cooling
| related.
|
| https://www.subzero-
| wolf.com/assistance/answers/wolf/common/...
| chinchilla2020 wrote:
| It's just increasing the power draw. There is no concept of
| 'stealing power from another phase'
| bruckie wrote:
| > solved thet by running the lighting on 220V with sets of
| two 110V bulbs in series
|
| Sounds like an exciting day when one of your bulbs burns out!
| bitdivision wrote:
| Bulbs normally burn out open, breaking the circuit. And in
| the unusual case that they don't, I would imagine the thin
| wires leading to the filament will melt, also breaking the
| circuit.
|
| And if all else fails you your circuit breaker should flip.
|
| If bulbs normally failed short, then you'd have circuit
| breaker's flipping a lot more often.
| jefftk wrote:
| Why? A burned-out bulb fails open not closed.
|
| If it failed closed then a bulb burning out would trip the
| circuit breaker.
| sokoloff wrote:
| > Why? A burned-out bulb fails closed not open.
|
| In electrical circuit terminology, "open" means "not
| connected" while "closed" means "connected/shorted".
|
| That's different from direct translation of Chinese (and
| I think several European languages) where "open the
| light" means to turn it on (by closing the circuit,
| naturally).
|
| I think it's most common English engineering usage (by
| far) to say that a burned out lamp fails open [circuit].
| jefftk wrote:
| Whoops, sorry, I had them reversed!
| sokoloff wrote:
| Interesting/random side note: modern mini Christmas light
| bulbs do burn out (mostly) closed:
| https://www.youtube.com/watch?v=0MOpfT0f7bQ&t=179s
| unethical_ban wrote:
| To close a circuit is to connect it, correct? So when the
| filament burns out, the circuit breaks, which is an open
| circuit, correct?
| jraph wrote:
| (edit: this comment is quite useless, I need to leave it to keep
| the discussion understandable)
|
| Interested in the answer which I don't have.
|
| That said, UK is wired to the continent, which runs at 230V, 50
| Hz.
|
| Everyone runs at the exact same frequency (same fluctuations) at
| any moment across the whole continent for technical reasons.
| (edit: UK is actually not synchronized with the continent, I
| didn't know that either).
|
| I guess having the about the same voltage as the rest of the
| continent is at least convenient (edit: apparently it's not
| exactly the same?).
|
| So I guess the question is US vs the European continent.
|
| Curious about the rest of America (North and South).
| projektfu wrote:
| North America is generally on 220-240V split phase with NEMA
| compatible plugs. In Mexico, the plugs are often ungrounded and
| only compatible, not identical to NEMA. In my house in the US I
| have mostly 120V circuits with a few 240V for appliances.
|
| Brazil is a bizarre mess of 127V single phase in most of the
| south and 220V single phase in the rest. They are supposed to
| use euro-style grounded receptacles but often have installed
| euro and NEMA bi-compatible plugs at 220V or 127V. A lot of 220
| circuits only carry 8-10A.
|
| Argentina uses the Australian style receptacle with 220V 50Hz.
|
| I'm not sure about the rest of South America but I think
| Uruguay and Paraguay are compatible with Argentina and the rest
| are on 60Hz and generally 220V.
|
| I'm surprised nobody mentioned Japan, and its varied system.
| mytailorisrich wrote:
| It's almost North America (and some friends) vs rest of the
| world, really:
|
| https://en.wikipedia.org/wiki/Mains_electricity_by_country
| [deleted]
| HPsquared wrote:
| UK interconnections to the continent are via HVDC links; the UK
| grid is not synchronous with the continental grid.
| ourlordcaffeine wrote:
| The uk grid is not synchronized with the european grid, it is
| just HVDC interconnected.
|
| You are right about the european grid, it is synchronized
| baz00 wrote:
| Picking a small point from your comment I find interesting, the
| voltages vary considerably across Europe depending on all sorts
| of factors.
|
| In the UK at least it's from around 216 to 253 volts. Mine is
| sitting at 249 now.
| [deleted]
| thrdbndndn wrote:
| TIL UK (or EU) uses 230V, not 220V like my country.
| oblio wrote:
| Po-ta-toe - po-ta-toh. You can use 220V stuff with 230V plugs.
| There are fluctuations for each network, anyway.
|
| Which country are you talking about?
| thrdbndndn wrote:
| China.
| alex3305 wrote:
| In The Netherlands the allowed voltage tolerance is 10% by law.
| So everything between 207V and 253V should be fine. And we also
| had 220V until 1989.
| jonatron wrote:
| UK actually uses 240V, which happens to be within +10% of 230V.
| soneil wrote:
| This is my favourite story about standardization.
|
| It used to be the continent used 220V, and the UK used 240V,
| until we standardized on 230V.
|
| The UK defines this as 230V -6% +10% (i.e. 216.2V - 253.0V),
| and nominal supply is 240V
|
| The continent defines this as 230V -10% +6% (i.e. 207.0V -
| 243.8V), and nominal supply is 220 or 230 by region.
|
| We called this harmonisation - in reality it's more like
| agreeing to disagree. We just fudged the tolerances until
| everyone was happy.
|
| (To put some context around this - most sites don't receive
| nominal supply. The actual voltage delivered depends on your
| distance to the local substation. Typically they over-deliver
| such that sites closest are a little over, sites furthest are
| a little under. If they actually delivered +-0%, sites at the
| edge of their network would be further from nominal. So end-
| user equipment should be built to expect variation.)
| thrdbndndn wrote:
| 230V+-6% should be enough for both though, right?
| soneil wrote:
| That'd give an upper bound of 243.8, which is far too
| close to 240 to be practical. As I tried to add, there is
| some necessary and natural deviation from nominal to
| account for path loss etc. 230+-6% only allows 240 to
| deviate by 1.5%, which isn't much scope at all.
|
| I believe +-10% was the traditional definition, so they
| just trimmed a little off the top end so it strayed less
| from Europe's definition - but not enough to actually
| affect nominal distribution.
| [deleted]
| jdietrich wrote:
| The UK used to be nominally 240V and a lot of EU countries used
| to be 220V, but we harmonised on 230V because it's comfortably
| within the tolerance bands for both. Nothing really changed in
| practice - UK installations still deliver about 240V and most
| EU installations deliver about 220V - but it was convenient to
| have a common standard.
| PaulKeeble wrote:
| My solar inverter consistently finds the UK grid at 243-245V.
| gulikoza wrote:
| My UPS is showing 236V at the moment (continental EU). We
| also used to have 220V IIRC, but are now closer to 240V it
| seems.
| rinron wrote:
| Here is a really great video that goes over the history
| https://www.youtube.com/watch?v=7yRGvMgieEU Sometimes we think
| about the technical reasons and forget of the human and the
| developmental process that can sometimes have an effect on how
| things are today. spoiler for the video - its because too many
| 110v light bulbs were already in place by the time 220v ones were
| made and it was too expensive/difficult to change. kind of
| reminds me of why the US never switched to metric.
| chociej wrote:
| Nobody's pointed it out yet, so I'll mention it:
|
| US voltage is 120 V (240 V phase to phase), not 110 V. And while
| 115 V is within service tolerances specified by ANSI C84.1 (114 V
| to 126 V), that's not the nominal value.
| c-linkage wrote:
| 110V is the Room Mean Squared (RMS) voltage.
|
| https://www.electrical4u.com/rms-or-root-mean-square-value-o...
| p1mrx wrote:
| No, 120V is the nominal RMS voltage; the peak is
| 120V*sqrt(2)[?]170V.
| andromaton wrote:
| The *root mean square is 120V.
| version_five wrote:
| Thanks, I'm in canada and I know we're 120, I was wondering if
| there was some reason the US was different and I'd just never
| heard about it. Iirc Japan, at least part of it, may actually
| be 110.
| _whiteCaps_ wrote:
| https://electronics.stackexchange.com/questions/614270/why-d.
| ..
|
| Japan uses 100V and 50/60 Hz depending on where you are in
| the country.
| hot_gril wrote:
| Speaking of Japan and frequency differences, one funny
| indirect consequence of the power differences is the video
| game Super Smash Bros Melee having separate NTSC and PAL
| versions, one at 60Hz and another at 50Hz, and consequently
| running at 60fps or 50fps (unless you override this at
| start). For good players, 50fps changed the game a lot, so
| they'd always use NTSC or override to 60. But PAL Melee
| also had other gameplay changes.
| aeyes wrote:
| A lot of games on the Mega Drive / Genesis didn't
| properly adjust their speed for PAL/NTSC, for example
| Sonic 1. They'd just run slower/faster according to VDP
| clock.
| w0mbat wrote:
| It's really annoying as Japan has lots of wonderful vintage
| secondhand synthesizers for sale, but being domestic market
| models they often have non-switching power supplies that
| require 100 V.
| _whiteCaps_ wrote:
| Yup! I've got a 120->100V step down transformer for my
| Minidisc player.
| ezfe wrote:
| While it's true, the US does supply 120V+-5%, appliances and
| equipment are operable on a much wider range.
|
| For example, my laptop charger is rated for 100-240V, which is
| not uncommon.
| version_five wrote:
| Laptops and other electronics are often the same between
| North America and europe, just with a different plug, thus
| the wide tolerance. For anything with a motor or coil this
| probably won't work
| doikor wrote:
| The 100V low end is there due to Japan.
| p1mrx wrote:
| 120V-5% is still greater than 110V.
|
| Power supplies are rated for 100V because that's the voltage
| in Japan. Though the tolerance would probably be useful for
| running a _really long_ US extension cord.
| MichaelZuo wrote:
| Technically they function fine as low as 95V for the worst
| case scenario, if they're well built.
| Moru wrote:
| My old computer started burning in some internal cabling
| about 30 years ago. Turns out our power wasn't 230 V when
| the power company came and set up a machine to make a
| graph. Some times of the day it could be much lower and
| that made my ancient atari converted to a towerbox to
| burn the cable to the harddrive on booting.
| Kirby64 wrote:
| Nothing to do with well built usually, just designed to
| work in all regions (specifically, Japan, which has 100V
| power for because of... reasons).
| analog31 wrote:
| That's a fairly recent development, mainly limited to
| switchmode power supplies.
| tragiclos wrote:
| It's about looking at supply vs demand. Electrical devices are
| often labeled by the minimum voltage they require to operate.
| 110 V is commonly used because the device can operate reliably
| on a 120 V distribution system.
| darknavi wrote:
| I learned recently that Japan is often on 100V power so I'd
| think a lot of international components would support
| 100-240V.
| rootusrootus wrote:
| It's a bit of a pet peeve of mine. We've been standardized on
| 240/120 since 1967, and still many people insist on saying 110
| and 220. It hasn't been 110V since well before 1967, either --
| it was increasing over time before they locked it at 120.
| TheCleric wrote:
| 220, 221, whatever it takes.
| hajile wrote:
| This is partially done to compensate for terrible wiring. Lots
| of people are fond of using small wires and going long
| distances leading to a lot of voltage drop. They often send
| 125v or so from the transformer which is 123-124 at the panel,
| 120 v or so at the receptacle, and >100v after someone decides
| to run something on a few hundred feet of #18 extension cord.
| codedokode wrote:
| I would like the voltage to be lowered even more, to 70 Volts.
| The reason is that 240V is very dangerous and can easily kill a
| human. But it seems governments care only about saving aluminium
| in wires rather than lives.
| mcpackieh wrote:
| > _But it seems governments care only about saving aluminium in
| wires rather than lives._
|
| That's needlessly inflammatory. Both the US and UK governments
| have numerous electrical standards and regulations designed to
| keep people safe despite unsafe power levels in residential
| wiring. You might argue that they aren't doing enough in this
| regard, but to say they _only_ care about saving metal just isn
| 't true.
| mdekkers wrote:
| Death by electrocution is incredibly rare in the EU, what are
| you talking about? Data, or hold your peace.
| codedokode wrote:
| Here is a recent case, for example [1]
|
| [1]
| https://www.dailymail.co.uk/news/article-12042495/Italian-
| gi...
| vel0city wrote:
| > But it seems governments care only about saving aluminium in
| wires rather than lives.
|
| I go even further on trying to save aluminum in my wires by not
| using any aluminum wires. Aluminum wiring is pretty rare in the
| US and largely considered a nightmare to work with.
| 1970-01-01 wrote:
| >Why do they use different frequencies like 50Hz, 60Hz?
|
| I've never found a technical answer for the 50Hz vs 60Hz
| question. It does seem to be an arbitrary standard.
| michaelrpeskin wrote:
| My guess: in the old days when electricity was new, power
| conversion was done with Rotary converters which were basically
| a fused motor-generator. To change voltage you had different
| winding and number of poles. So if you were at 60 Hz, you have
| the magic of being divisible by a lot of numbers and you could
| easily go up down by common integer values.
|
| Then when Europe was standardizing, they wanted to be all
| metric, and 50 was close enough to 60 and still could become
| 100 by doubling.
|
| I don't know, those are just pure guesses.
|
| I think when you come from the engineering/tinkering side of
| things, you like units with easy integer fractions (12 inches
| in a foot is really easy to work with at human scale). When you
| come from the science side of things, you like easy decimals
| and that's why metric wins there.
| nzach wrote:
| My understanding is that this choice is a balancing act between
| having good efficiency for long distances transmissions (230v)
| and having a lower peak load in the grid (110v) for desely
| populated areas. But I'm no expert in this matter.
|
| Where I live (Brazil) is commom to have both. In the big cities
| you will find 110v and outside that you are more likely to find
| 220v. And yes, it is a pain if you move from a 220v city to a
| 110v one. But besides that most people don't care about having 2
| standards.
|
| For anyone interested there is a semi-relevant
| TechnologyConnections video[0] where he discusses the popularity
| of kettles as way to heat water in the US.
|
| [0] - https://www.youtube.com/watch?v=_yMMTVVJI4c
| johann8384 wrote:
| The lines in your neighborhood that feed your house are 7200v,
| that goes into a transformer in the yard or on the pole which
| provides 240v to your house. Larger transmission lines are
| 38000 volts. There are other voltages in place as well.
| throw0101b wrote:
| _Kathy Loves Physics & History_ did a video on this, and the
| reason is basically legacy:
|
| * https://www.youtube.com/watch?v=7yRGvMgieEU
|
| Edison originally purchased others' dynamos, especially Wallace-
| Farmer, which was 110V (DC):
|
| * https://americanhistory.si.edu/collections/search/object/nma...
|
| * https://en.wikipedia.org/wiki/Moses_G._Farmer
|
| So Edison's long-legged Mary-Ann was also 110V:
|
| * https://www.collectorsweekly.com/stories/82967-thomas-edison...
|
| * https://edison.rutgers.edu/life-of-edison/inventions?view=ar...
|
| * https://americanhistory.si.edu/collections/search/object/nma...
|
| Light bulbs in the early 1900s were first designed for lower
| voltages, and the grid slowly raised things over time, but at
| some point they couldn't go any higher because it would start
| blowing things, so they were 'stuck' in the 110-120V range.
| tomohawk wrote:
| In the US, you can have electric receptacles in bathrooms. In
| fact, code requires it. You can plug in 120V electronics and
| appliances no big deal.
|
| In the UK, this is not allowed because 240V is not a good idea in
| bathrooms.
| kypro wrote:
| Most bathrooms in UK hotels will have two pin 115v & 230v
| outlets for shavers. You can get them installed in homes too I
| believe, but most residential properties don't have them.
|
| They really are just for shavers though. You can't run anything
| high power without blowing the fuse. I believe Americans often
| use hairdryers in bathrooms. We definitely can't do that.
|
| That said, we do have electric showers in UK bathrooms but
| legally those need to have a kill switch installed.
| tzs wrote:
| But it is allowed in most of the rest of Europe. I believe they
| do require those to have GFCI (as does the US since 1975). Does
| the UK disallow them even with GFCI?
| kelnos wrote:
| I found it somewhat funny that the question included:
|
| > _Explain me with calculation._
|
| As with many things related to technology, decisions are very
| often made for seemingly arbitrary (or political, or economic, or
| competitive-advantage) reasons, not because of some calculation
| that was done that proved a decision optimal.
| lprd wrote:
| I spent about a decade in Europe and really enjoyed learning
| about how their electrical grid works. The ability to directly
| plug most appliances without needing to buy extra adapters was
| amazing. Boiling water also took half the amount of time.
|
| If memory serves, Thomas Edison used a 110v DC power supply to
| create a system of electricity for people. Meanwhile, Nikola
| Tesla invented the three-phase 240v Alternating Current (AC).
| Tesla was clearly a man ahead of his time (even by today's
| standards).
|
| tldr; Europe's grid is vastly superior to America's.
| mixmastamyk wrote:
| There's a special plug for the oven, no adapter needed.
| gattilorenz wrote:
| "The ability to directly plug most appliances without needing
| to buy extra adapters was amazing" unless you live in Italy,
| Switzerland, France (they have a socket with the ground
| sticking out I think), Poland, the UK, Denmark... it's getting
| better and better due to the use of DC and the reduced need for
| grounding, though
| Egoist wrote:
| Some devices can also be more efficient when using 230V. Eg: PSUs
|
| https://electronics.stackexchange.com/questions/469913/compu...
| getarofilter wrote:
| [dead]
| vonwoodson wrote:
| Because, Freedom. And, because America. **===
|
| Now, I'm going to go talk to My Fellow 'Mericans about continuing
| to not use the metric system.
| otherme123 wrote:
| I am european. Regarding to the metric system, IMO americans
| are wrong. But regarding to electricity, americans have it
| better than Europe: France, UK, Italy, Switzerland, Denmark and
| Germany have their own sockets, and that after a recent spread
| of the german Schuko. We shouldn't lecture americans about
| changing things to use a standard.
| vonwoodson wrote:
| There's nothing "wrong" about being The Best! #FREEDOM
| #TheseColorsDontRun #Merica
| HPsquared wrote:
| The 50Hz and 60Hz is quite noticeable. I'm used to hearing mains
| hum at 50 Hz, so hearing it at 60 Hz sounds a little different.
| (You can sometimes hear it in audio recordings etc).
|
| 50 Hz is about a G, and 60 Hz is about a B-flat. Video
| comparison: https://youtu.be/pMtn-loUrg8
| dvh wrote:
| There was a video recently where YouTuber diodegonewild was
| fixing old power supply, he turned it on, listened to it and
| said "the transformer has DC offset on it, because it's humming
| at 50Hz, the magnetostriction doesn't care about polarity,
| healthy transformer hums at 100Hz, I think one of the diodes in
| bridge rectifier is bad" and he was right.
|
| https://www.youtube.com/watch?v=bWxS2njU-JI&t=355s
| ChrisArchitect wrote:
| (2014)
| consp wrote:
| It's not all that weird though. Until the 1970's we had (in NL)
| 127 in some and 220v in other places which could either be 127v
| to ground, 220v to ground or 220v line-to-line. By around mid
| 2000's everything was switched to 230/400v for standardization in
| Europe, so it's not that long ago we still had some lower
| voltages.
| sph wrote:
| Relevant Technology Connections video: "The US electrical system
| is not 120V" https://www.youtube.com/watch?v=jMmUoZh3Hq4
| PrimeMcFly wrote:
| Better yet why does the UK use those ridiculous cumbersome over-
| designed plugs?
|
| Or, even more curious, why are so many British authorities so
| bizarrely (to the point it's funny) protective over electricity,
| fining people and threatening to call police on people who try to
| charge their phones in train stations, for example?
| tgbugs wrote:
| The tradition answer to this question is surely this wonderful
| Tom Scott video: https://www.youtube.com/watch?v=UEfP1OKKz_Q.
| dwb wrote:
| Granted I grew up with them, but I like them. They can be
| annoying to travel with, and accidentally stepping on them
| barefoot is very painful, but apart from that the size is
| handy. I've never had them slip out of the socket, for
| instance, like US or EU plugs.
| PrimeMcFly wrote:
| > They can be annoying to travel with
|
| That's my main problem since I travel a lot, or used to at
| least.
| vladvasiliu wrote:
| > I've never had them slip out of the socket, for instance,
| like US or EU plugs.
|
| Aside from old-style type-C plugs (two prongs) in old
| sockets, I've never seen an EU plug work itself loose in a
| socket, let alone slip out of it. Usually, there's the
| reverse problem: they're difficult to unplug, even when you
| want to.
| JoeAltmaier wrote:
| That always seemed to me, to be a fabulous danger. Reach for
| your towel on the counter, tangled with the hair dryer cord
| and the hair-dryer is pulled into the bathtub. Yow!
|
| In the US, the cord would likely pull out of the wall,
| safely.
| pjc50 wrote:
| > hair-dryer is pulled into the bathtub
|
| What hairdryer? British building regs restrict you to an
| isolated "shaver" socket in the bathroom which takes
| different plugs. You can't drop a hairdryer in the bath
| unless you play silly games with extension cables.
| OkayPhysicist wrote:
| The British paranoia about bathroom electrical devices
| has always amused me. Stick a GFCI on every outlet in the
| bathroom, then it doesn't matter if you're swimming with
| a toaster or an electric shaver. Heck, it was uncommon to
| even find a light switch inside the restroom.
| jraph wrote:
| > cumbersome over-designed
|
| It's a pain they are not the same as the rest of Europe, but
| what is cumbersome and over-designed about UK plugs?
|
| Follow up question, why Swiss plug needed to be so close to the
| rest of Europe, but different anyway? (same distance between
| the 2 pins, but the pins are a bit thinner and the ground is in
| the opposite way).
| mytailorisrich wrote:
| British plugs are big but they are flat (cable runs parallel
| to wall), which actually makes them less cumbersome than EU
| ones because you only need a small gap between wall and
| furniture/whatever.
| crote wrote:
| A very significant fraction of Schuko plugs is also
| 90-degree angled, though. Angled is neat for furniture, but
| straight-out is better for unplugging and high-density
| power strips.
| PrimeMcFly wrote:
| > It's a pain they are not the same as the rest of Europe,
| but what is cumbersome and over-designed about UK plugs?
|
| The size is definitely cumbersome. Look how much bigger they
| are than US/EU/AU plugs, basically any other countries plugs.
|
| I'd call having a fuse in the plug itself over-designed.
|
| > Follow up question, why Swiss plug needed to be so close to
| the rest of Europe, but different anyway?
|
| I have the same question about AU plugs. Literally the same
| as the US plugs (newer ones that don't have one side larger
| at least), just at an angle.
| jonatron wrote:
| The fuse in the plug is necessary to protect the wiring on
| ring circuits.
| PrimeMcFly wrote:
| Other countries get by just fine without it.
| wongarsu wrote:
| Other countries don't use ring circuits to the extend the
| British do. We just rate every outlet to the specs of the
| wire in the wall, but the British have a 30A ring that
| serves multiple 13A outlets. As a consequence they need
| to protect the outlets (and device wires) from
| overcurrent somewhere in the circuit.
| mixmastamyk wrote:
| Believe it has to with lowering the cost of rebuilding
| after the war.
| wongarsu wrote:
| The fuse in the plug was _chosen_ to protect wiring on
| ring circuits. They could also have put the fuse in the
| wall socket. After all, they already put switches on
| them. Of course then you would have to go with the screw-
| in fuse design that was used in circuit breakers back
| then, instead of the fuse design in UK plugs.
| mhandley wrote:
| > I'd call having a fuse in the plug itself over-designed.
|
| Personally, I'm quite happy that all my lower power devices
| with relatively thin power cables are protected by a 3A
| fuse. There's no risk of causing those cables to catch fire
| if there's a fault that draws 20A, which isn't enough to
| blow the 32A breaker on that ring.
|
| How much difference it makes in practice though? Pretty
| sure that if I short the power at the device end of a 5A
| cable, the 32A breaker would blow before the cable caught
| fire. But I'm happy not to depend on that.
| PrimeMcFly wrote:
| I've never had issues in the US/AU/EU, so I really
| question how useful it is compared to the amount of
| incidents it is actually offering protection against.
|
| Seems to me it's somewhat like having an additional
| seatbelt for your head, which might protect against
| whiplash but isn't justified by the inconvenience.
| jdietrich wrote:
| The size is cumbersome, but folding plugs are available for
| devices like phone chargers - the dummy earth pin is
| retractable, so the overall size of the charger is
| essentially the same as a US or EU charger.
|
| _> I'd call having a fuse in the plug itself over-
| designed._
|
| I wouldn't. A UK mains circuit typically has a 32A breaker.
| Pulling that much current through an appliance that's
| designed for a fraction of an amp or a cable that's
| designed for 3A is obviously a very hazardous fault
| condition. Some appliances have a built-in fuse, but many
| don't and that still doesn't offer the same level of
| protection as a suitably-sized fuse in the plug.
| PrimeMcFly wrote:
| > The size is cumbersome, but folding plugs are available
| for devices like phone chargers - the dummy earth pin is
| retractable, so the overall size of the charger is
| essentially the same as a US or EU charger.
|
| How much does a folding plug fold? Look how minimal
| this[0] is, I've never seen any UK plug anywhere close to
| that size.
|
| > I wouldn't
|
| Any reason the fuse couldn't go in the socket instead?
|
| [0] https://i0.wp.com/www.cablesgo.com/wp-
| content/uploads/2018/0...
| drcongo wrote:
| > Any reason the fuse couldn't go in the socket instead?
|
| Because changing the fuse in a socket just because you're
| unplugging a lamp and plugging in a kettle would be very
| stupid. With the fuse in the plug, you have the correct
| fuse in every plug.
| awhitby wrote:
| For one thing, AU 2-prong plugs have a much more physically
| secure connection than equivalent US plugs. The angled
| prongs mean there's no rotational axis about which the plug
| can fall out. Of course it also means the prongs can't
| really fold away for storage.
| hooch wrote:
| How does ChatGPT come anywhere close in usefulness compared to
| the breadth and fan-out of facts, opinion, supports and counter-
| arguments offered by this format?
| bloomingeek wrote:
| "In some rare situations 220V might be more dangerous to touch."
|
| Uh huh, here's an idea, go ahead and test that out for yourself!
| Faaak wrote:
| And with 30mA GFCIs, the risk is greatly diminished
| temporallobe wrote:
| I've lived in UK, Europe, and the US and I don't really see a
| problem with either system. The 120V system is perfectly
| sufficient for most cases, even refrigerators and other large
| appliances. I suppose the one advantage a 220V system has is that
| you can put a stove or dryer anywhere, and you can run certain
| appliances, such as steamers and irons with way more power. On
| the other hand I find the UK's plugs to be comically large
| compared to the US's petite counterparts. Some European houses
| even have a few 3-phase 380V outlets for heavy duty equipment,
| which would be exceedingly rare in the US.
| rekoil wrote:
| > Some European houses even have a few 3-phase 380V outlets for
| heavy duty equipment, which would be exceedingly rare in the
| US.
|
| My European 50m2 apartment has two.
| sleepybrett wrote:
| similar story to railroad gauges
| SeanLuke wrote:
| There were many factually correct, and even historically
| interesting responses. But not a single response answered the
| question.
| wongarsu wrote:
| I'm not sure there is a good answer, beyond "the US stuck with
| Edison's 110V, Europe went with 230V because it's cheaper".
| Both 110V and 230V are reasonable choices. And of course
| technically the US primarily uses 230V split between two
| phases. But Europe mostly uses 3-phase 400V, with each phase
| delivering 230V (because phases are 120deg offset to each
| other), so then we are just talking about 230V vs 400V, and two
| vs three phases.
| oblio wrote:
| > Both 110V and 230V are reasonable choices.
|
| Are they, though? With modern appliances, power requirements
| are going up and 110V is struggling to keep up. One example
| would be an induction hob.
|
| I know that technically US homes can access 230V but they
| aren't wired for that, probably 99% are wired just for 110V
| except for maybe a few special lines.
| wil421 wrote:
| Laundry, stove, and ovens use 240V outlets (assuming no
| gas). It's not very common but I know a few people with
| wood working tools who have installed 240v outlets. Wood
| framed houses make it easy to change wiring.
|
| To change my gas stove/oven back to 240v induction would be
| a 15 foot run of romex, a new outlet, and probably an
| updated circuit breaker. Possible for a DIYer to do.
| vel0city wrote:
| Every US home I've lived in had 240V access in the kitchen
| for appliances like electric ranges. They absolutely _are_
| wired for that. Practically nobody 's house _only_ has
| 120V.
| gibspaulding wrote:
| It sounds like you've always lived in relatively new/high
| end houses then.
|
| Older houses might have a dedicated 240 plug for the
| dryer and the stove if they're not natural gass, but for
| everything else there are plenty of homes full of
| ungrounded 10 amp 120v circuits.
| vel0city wrote:
| My current house was built in '82. Is that a new house?
| That's 41 years old at this point. Its a pretty average
| single family suburban build for the time, not anything
| especially fancy even for its day. Loads of houses we
| looked at in the area were built in the 70s and 60s and
| often had electric 240V appliances in the kitchen. That's
| about 60 years old, is that a new? A single car garage
| 1500sqft 3bdr house in a suburb sound like a high end
| house?
|
| And yeah, my house is full of 120V circuits, but once
| again the house has 240V at the panel and could run 240V
| anywhere in the house if needed. As you pointed out, they
| probably do have a 240V plug for the dryer, ergo they've
| got 240V service at the property, so they could wire the
| kitchen if there's no wiring already. Once again,
| practically nobody has _only_ 120V service at their home.
| sbradford26 wrote:
| Yeah the only situation I can think of only 120v being
| available in a house is if it is a separate unit running
| off a 120v sub panel from the main building. The other
| option would be some off grid setups for like a tiny home
| might only run 120v. That is mostly because anything that
| would require 240v would be too power hungry to run off
| of the solar system.
| wongarsu wrote:
| Interestingly enough, European oven/hob combos mostly run
| on 400V 3-phase power. Same for many tankless water
| heaters. That's certainly one advantage of 230V per phase.
| It's probably also one factor in the decision to power
| things by gas vs electric.
| rootusrootus wrote:
| But are they more powerful? AFAIK it's pretty common for
| a European range to be in the 7000-10000 watt range.
| That's also normal in the US on single phase 240V. And I
| can go buy a 36000 watt tankless water heater from Home
| Depot. I think it's a wash, either system can deliver
| however much power you need.
|
| The reason for gas in the US is because people like it.
| It's been seen as upscale for decades to have a gas
| cooktop. It also helps that gas water heaters don't
| require electricity and work in an outage. Our
| residential natural gas distribution network is extensive
| and reliable, and it's pretty straightforward to use the
| same appliances on propane for people out in the sticks.
| vel0city wrote:
| Depending on the market it can also be cheaper per BTU to
| heat with gas than with electricity, at least resistive
| heating. Heat pumps are starting to challenge that math,
| but with higher upfront costs and more complexity as
| tradeoffs.
| michaelt wrote:
| _> With modern appliances, power requirements are going up_
|
| Things like lightbulbs and TVs and computers and
| refrigerators are using less power than ever before.
|
| Of course, if people are buying electric cars or replacing
| gas furnaces with electric heat pumps, then you're right on
| that side of things.
| oblio wrote:
| > Things like lightbulbs and TVs and computers and
| refrigerators are using less power than ever before.
|
| Are they, though?
|
| Lightbulbs, sure, we won with LEDs.
|
| But TVs, especially the huge, high brightness ones we
| have nowadays? And with the extra computing needed?
|
| Computers, same, I only see power usage going up. I mean
| PCs, we're not comparing things with mainframes here :-)
|
| Refrigerators: are they really more efficient?
|
| Now add: heat pump, induction stove, electric oven, more
| powerful AC, humidifiers/dehumidifiers, etc.
| michaelt wrote:
| Compared to the age of CRTs, modern TVs are much more
| power efficient.
|
| And compared to the age of the Pentium 4 with its 100W+
| TDP, laptops now outsell desktop computers by a long way.
|
| (I would agree that things like high-end gaming GPUs are
| using more power than ever before - but they're also a
| much smaller % of sales than ever before)
| oblio wrote:
| > Compared to the age of CRTs, modern TVs are much more
| power efficient.
|
| According to the internet a CRT TV used to use about
| 100W, while a big LCD TV can use more.
|
| Regarding desktops, don't forget that these days we have
| many more electronic device in a home. Smart speakers,
| home media devices, consoles, etc, etc. Electronics
| probably use, in aggregate 5-10x what the old family PC
| used to use, I'd imagine.
| selectodude wrote:
| A 32" Sony trinitron would pull down about 200W. An 85"
| LCD will pull down about 150W.
| bluGill wrote:
| Though in the CRT days 19" was the most common size
| (large did exist). I'm not sure what the most common size
| TV is today, but it is bigger than that.
| dontlaugh wrote:
| Gaming PCs are actually getting close to the safe limits
| for low voltage.
| sbradford26 wrote:
| Fundamentally the US just wires things differently. If a
| house has an electric or induction hob(Cooktop) it will be
| permanently wired for 240v. All your high power devices
| such as HVAC, ovens, cooktops, and EV chargers have
| dedicated lines at 240v for them. Every house in the US
| other than some super niche scenarios has 240V. Yes largely
| most everything is wired for 120V and only a few special
| lines at 240v but that is because those are the only things
| that really require more power.
| ponector wrote:
| While in Europe every regular socket has 230V but
| induction has 400V with 5-wired connection. It is amazing
| how fast it can boil water!
| bluGill wrote:
| Power = V*A. You can get any given power output out of
| any voltage by following the formula. The number of wires
| is not a factor at all. Number of wires and voltage is a
| factor in cost of install of course, but nothing else.
| sbradford26 wrote:
| Yes European ones will run on higher voltage but largely
| they are equally powerful.
|
| US Version: https://www.bosch-
| home.com/us/productslist/cooking-baking/co...
|
| UK Version: https://www.bosch-home.co.uk/product-
| list/cooking-baking/hob...
|
| Largely they have the same power output. While the total
| power available is actually higher for the US version at
| 12kW versus 11.1 kW for the UK version. That is because
| the US version needs to be on a 50 amp 240v circuit
| versus the max 16 amp circuit for the UK version.
|
| Even this Bosch one: https://www.bosch-
| home.co.uk/product-list/cooking-baking/hob... Which
| clearly calls out 400v 3 phase has a lower power output
| at 7.4 kW.
|
| The max output to a single pan/pot typically is going to
| max out around 3.3-3.7 kW. I don't know the exact
| reasoning behind that but I assume it might cause issues
| with cookware if you go much higher than that.
| [deleted]
| johann8384 wrote:
| US Power is typically 240v split-phase, a single phase, not
| two phases. The transformer is 7200v to 240v. The Neutral
| line to your house is center tapped on the transformer giving
| you 120v from Hot to Neutral and 240v from Hot to Hot. I have
| L14-30 and L5-30 outlets throughout my house and property for
| example which lets me run higher voltage/amperage workloads
| more easily. My workshop has an isolation transformer which
| is 240v primary and 120v secondary. This allows me to run 80A
| of 120v "stuff" in my workshop but it's a 40A 240v load from
| the perspective of the main panel in the house.
| JadeNB wrote:
| Do you know the answer? (Of course your remark makes sense even
| if you don't, but, if you do, then I'd love to know.)
| antegamisou wrote:
| Welcome to *.stackexchange.com
| tyingq wrote:
| The one explaining that Edison's DC system they were competing
| with, in the US, was using ~100v DC. And the public
| disinformation campaign characterizing AC as unsafe. Including
| attacking anything higher than approximately 100v as unsafe.
| That seemed like it answered the question to me.
| refurb wrote:
| "Edison's lamps were 100V" is in one of the answers.
| Ekaros wrote:
| And to me this seems most obvious answers. With possibility
| that you had other resistive loads at that voltage already
| sold. And people would be rather gross if they had to replace
| them.
| wiredfool wrote:
| So, not only is the UK 230v, it's also wired in a ring (i.e.,
| your circuit isn't a branch from your junction box, it's a full
| loop). So, for a given power capacity, you can use much less
| copper.
|
| (from the wiki: https://en.wikipedia.org/wiki/Electrical_wiring
| _in_the_Unite...) UK fixed wiring circuits,
| unlike those found in almost all other countries, make
| widespread use of ring circuit designs, as well as radial
| circuit designs often seen in other countries. (This was one of
| the recommendations of the Electrical Installations Committee,
| convened in 1942 as part of the Post War Building Studies
| programme, which in 1944 determined that the ring final circuit
| offered a more efficient and lower cost method to support a
| greater number of sockets.[6]) It continues to be the usual
| wiring method for domestic and light commercial socket and
| device wiring in the UK. Lighting circuits, which typically
| have lower power requirements, are usually radially wired,
| confusingly sometimes called "loop" wiring.
|
| So, the why is: More power, less copper, and that's really
| useful when you're resource constrained because someone has
| declared war on you and is blockading your coast, or you're
| recovering from that.
| jqpabc123 wrote:
| There is not one single all encompassing answer.
|
| Safety was one significant concern. 230-240V is more likely to
| stop a person's heart. 220 is available in most US homes for
| specific cases where it is more practical.
|
| Speaking from experience, I don't think it is uncommon for a
| person to have been electrically shocked at some point in their
| lives --- often when they were a child.
| wongarsu wrote:
| Maybe common in the US. Europe takes plug and outlet design
| more serious (as a consequence of 230V), and while the UK
| plug and continental Europe's Schuko plug are very different
| both make it basically impossible to accidentally shock
| yourself.
| LinAGKar wrote:
| Not impossible with the Schuko, it's still possible for
| something to get caught in it and touch the pins when it's
| partially inserted, that's happened to me. It's better when
| only the tip of the pins are exposed, as on the UK plug and
| the Europlug.
| jqpabc123 wrote:
| The plug is an issue but so is the socket.
|
| What keeps a kid from sticking something metal into it?
| james_a_craig wrote:
| On UK plugs at least, there are shutters and you need to
| insert something into the earth pin slot before they will
| allow you to access the live/neutral pins. On better
| sockets, the shutters then need simultaneous pressure on
| both live/neutral to completely release. The actual
| contacts in the socket are recessed too.
|
| UK plugs and sockets are really, really, really safe.
| Except to stand on.
| kwhitefoot wrote:
| Same on modern Schuko.
| ovi256 wrote:
| There is a hole cover plate that has to be pushed by
| rounded plug pins to pivot and unlock the socket holes.
|
| You can try pushing with something like a screwdriver (to
| test for live) and it's hard to pivot the plate (feels
| like it needs both pins to pivot), and a non round tool
| snags on the plastic cover plate.
| bluGill wrote:
| In the US code requires shutters so you can't stick
| anything into the socket other than the correct plug
| (IIRC as of 2008?). Other responses are implying the UK
| (and I assume EU) now require that too.
|
| On the other end, in India I saw a power strip that would
| accept EU, UK, or US plugs. I took one look and refused
| to get close, but someone else plugged my laptop in and
| it worked. (everything got 240 volts, which my laptop
| power supply was fine with)
| jandrewrogers wrote:
| I've seen people shock themselves using the UK plugs with
| casual handling more than once, it is definitely possible.
| macrolime wrote:
| I'm in Europe and I've been shocked a few times by 220V and
| I know plenty of other who has too. It's usually not from
| regular wall sockets, but wires with broken insulation or
| working on things where parts of a circuit is uninsulated.
| jqpabc123 wrote:
| Plugs are only part of the safety issue.
|
| Wire insulation deteriorates over time. Rodents like to
| chew through it. Water can find it's way in through
| plumbing or roof leaks. Higher voltage is more likely to
| start a fire in these instances.
| izacus wrote:
| Are there any stats showing that Europe has more issues
| with electricutions and electrical fires?
| jqpabc123 wrote:
| According to the European Fire Safety Alliance:
| The total number of fires of electrical origin in the EU
| is estimated to be 273,000 per year.
|
| According to the US National Fire Protection Assocation:
| Fire departments responded to an estimated average of
| 46,700 home fires involving electrical failure or
| malfunction each year in 2015-2019.
|
| Stats aside, which do you think will cause a bigger
| spark, 110 or 220?
|
| https://www.europeanfiresafetyalliance.org/publications/w
| hit...
|
| https://www.nfpa.org/News-and-Research/Data-research-and-
| too...
| bluGill wrote:
| Those numbers are not the same. EU is covering
| everything, while US only home fires. And there is a
| significant population difference in play as well.
| jahnu wrote:
| Even stranger than that, Japan has two grids, one at 50Hz and one
| at 60Hz!
| askvictor wrote:
| ...which were completely isolated, until Fukushima led to power
| shortages so they hurriedly linked /are linking the two with DC
| interconnects.
| hot_gril wrote:
| Every comment in this thread is mentioning a different angle of
| advantage/disadvantage between the two. I've given up on
| determining the winner, but that's ok, I'm just learning a lot
| about home power distribution.
| mrguyorama wrote:
| There is no winner. It's a simple API, with many correct
| answers. The US ossified on it's system, and different European
| countries did the same.
|
| It's just a standard "Emacs vs VIM" flamewar.
| hot_gril wrote:
| Well if you compare it to emacs vs vim, that's making me
| think there _is_ a correct answer.
| bluGill wrote:
| There is, but you are wrong... Hang on, let me go find my
| old flame war cheat sheet I need to throw a few more
| insults at you.
|
| /s
| rootusrootus wrote:
| > The US ossified on it's system
|
| Though it is crass, I'll say it. A silver lining to the
| tremendous infrastructure damage caused by world wars in
| Europe is that ossification was interrupted.
| rootusrootus wrote:
| > I've given up on determining the winner
|
| That's because there is no winner. Nobody is doing something in
| the US that is impossible in Europe, or vice versa. There are
| upsides to both approaches, and different trade-offs, but
| everyone is getting enough power.
| darknavi wrote:
| Tom Scott has a fun video not on voltage but on the merits of
| the wall sockets them selves:
|
| https://www.youtube.com/watch?v=UEfP1OKKz_Q
| hot_gril wrote:
| I don't normally like YouTube talking videos, but this one is
| really good and to-the-point. Will say in response though, at
| least 120V makes this less of a safety issue.
| dim13 wrote:
| Old joke: why USA use 110V and UdSSR 220V? Answer: because half
| of it will be stollen in transition anyway.
| noobermin wrote:
| I moved from the US to Singapore which uses 230, and that coupled
| with the humid environment makes things a lot less unsafe. That
| plus old HDB electrical work isn't always the best. Getting
| shocked and damaging electronics because a socket is lose is very
| common here, and can be life threatening. I never had to worry
| about this (at least as much). Floating ground here on the other
| hand is device or even life threatening which is a real issue as
| most chargers especially recent GaN ones do NOT have a ground
| prong.
| BeetleB wrote:
| You should not get downvoted for this. The whole world isn't as
| safe as Europe. I spent time in a country with 220V, and in
| those days there was virtually nothing preventing you from
| getting shocked (I know as I've been shocked). The prongs were
| round, and you could easily touch the metal while inserting and
| get a shock.
|
| Another problem: Some of the plug/socket combinations were
| fairly loose. It wasn't a tight fit. So if you're ironing, it
| was not unusual for the plug to be partially out of the socket.
| stephen_g wrote:
| I'm really interested to hear more details about how this is
| possible, because it's scary but fascinating!
|
| Here in Australia we have 230V, and getting shocked is not at
| all common - we have very strict electrical standards for both
| installations and devices, residual current devices (GFCI
| equilivalents) now required on every single circuit, everything
| either has a proper ground or is double-insulated (unlike the
| US sockets here without a ground pin are very uncommon because
| you can't plug a lot of devices in to them) etc.
|
| There was a possibility where you could pull the plug out very
| slightly and slide something like a knife in between the plug
| and socket and touch the active and neutral pins, so the
| standards were changed many years ago now so compliant plugs
| now have insulation on the live and neutral pins for the first
| half of their length (see an example plug here - https://au.rs-
| online.com/web/p/power-cords/0321168 ).
| mytailorisrich wrote:
| Getting shocked is a symptom of faulty electrics, not of using
| 230V (even in a high humidity environment).
| jraph wrote:
| > that coupled with the humid environment makes things a lot
| less unsafe
|
| Safer? Why?
| noobermin wrote:
| When I am fly by night posting I do be using those double
| negatives.
|
| I meant less safe.
| zuppy wrote:
| this is not an issue in Europe. what kind of plugs do you use
| in Singapore? the EU plug doesn't let you get shocked when
| pulling the cord. i am willing to bet it's because of that, not
| because of 220 vs 110. it has never been an issue in my life
| and i don't get shocked ... ever.
|
| edit: after a quick research i thing the reason is the socket:
| https://www.everyworks.com/reasons-why-your-singapore-electr...
| we don't use this, we have a small hole inside ours and it's
| impossible to touch the live while the plug is connected
| ketzu wrote:
| Apparently they use british Type G plugs. ( https://en.wikipe
| dia.org/wiki/AC_power_plugs_and_sockets#/me... )
| zuppy wrote:
| after a quick research, i think it's the socket not the
| plug, it's easier to touch the live wire if the socket is
| flat.
|
| edit: can't reply to the child comments, maybe there's a
| time limit, i'll answer here. i have no experience with the
| british plugs, if you say it's impossible i believe you. i
| don't understand, though, how does this happen to the
| person from the top message.
| the_mitsuhiko wrote:
| Neither on British nor European Plugs can you touch a
| live plug when only partially inserted.
| Well_Keen wrote:
| You absolutely can. I've personally be accidentally
| shocked twice by pulling a firmly inserted plug out of a
| socket, but it was my own fault. Get the plug partly
| pulled out then readjust your hand to get more grip
| around the side of the plug and in doing so accidentally
| touch the non-insulated section of the live prong just as
| it is in contact with the live terminal
| jdietrich wrote:
| If both the plug and socket are correctly made, it's
| physically impossible - by the time the contacts on the
| plug are exposed, they've disconnected from the contacts
| in the socket. No matter how much you prod and poke, you
| should only ever come into contact with an insulated
| sleeve or a non-energised contact. Unfortunately there
| are a lot of non-compliant plugs being sold by
| disreputable online retailers.
|
| It is possible to get a very mild shock from the plug
| contacts if the input capacitors of the appliance haven't
| fully discharged. This shouldn't happen with properly-
| designed appliances, but it's very unlikely to be
| dangerous if it does happen.
| physicsguy wrote:
| There's a long earth pin on the top of British plugs, the
| socket doesn't open the holes to allow the other two pins
| in until that's already inserted to the appropriate
| depth. So you can't stick anything in to the socket and
| touch a live wire.
| circuit10 wrote:
| If they use UK plugs it should be impossible to touch
| that because there's a shutter that covers it until the
| earth pin in put in
|
| Here's a video by Tom Scott about why UK plugs are safer:
| https://youtu.be/UEfP1OKKz_Q?si=f8UxqwhN4tmYxFMk
| mnd999 wrote:
| Should be the same for type G, the pins are shielded such
| that it shouldn't be possible for them to have exposed metal
| and be live at the same time.
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(page generated 2023-08-29 23:01 UTC)