I'm typically not a big EU defender but it's one of the thing that is really oh-so-much better in the EU: every time I go to the US having to plug stuff into electrical outlet feels like I've been beamed back to the 1950s or something. Plugs don't fit properly: they simply feel loose. Or you need to use super bulky, non-sensical, plugs.
That and switches (like light switches): not only we've got way more variety in the EU but they also all feel of better quality.
Both electrical outlets and switches in the US do also look old and dated. Just like they feel when using them: old and outdated.
I am unsure if this is a common mindset for Americans, but I personally perceived Europe as rather backward and out-of-date, technologically. I don't know why I got that idea, other than "Europe is more ancient than us" and believing that USA is the nexus and origin of all innovation.
So, when I arrived in Barcelona and Catalonia, I was pleasantly, mildly surprised that not only had Europe kept pace with us techno-mages in America, but they had some kind of parallel evolution going on, in terms of connectors, interfaces, protocols, etc.
My fiancée was sort of mystified, because my favorite subject of photography was not landmarks or her pretty face, but the circuit breaker box, the rear of her television set, the A/C unit, and any other cool, distinctly Euro-tech instances I could identify around there.
I tried helping her adjust/fix her aerial TV antenna, got zapped a few times; discovered that Catalonian TV antennas are energized with a few volts for whatever reason; decided that Euro-tech is beyond my expertise to tinker with on someone else's behalf, especially a native family.
Thankfully, I didn't have any portable electronics or appliances in my luggage that needed adapters or plugs, but the experience was truly humbling, and eye-opening, and I returned to the United States with a better calibrated worldview.
The US technology advantage is in software, hardware, biotech/pharma, AI, some advanced robotics (China is leading in general robotics), quantum, aerospace, military, medtech.
Competitively the US does well in energy tech and agriculture tech. The US is #2 in wind power, #2 in solar power, #1 in nuclear power, along with being the world's biggest oil & natural gas producer. The US industrial rail system is also an epic scale marvel, while its consumer rail system is pathetic.
It's definitely not elite in most infrastructure (including electrical plugs).
As for the TV antenna, centralized European installations tend to have really long cable runs, even more so for cable TV, and there's a wideband PA in the basement.
The US is innovative but can't be bothered to get the boring stuff right.
Meanwhile Europe standardized bank transfers with IBAN, killed connector type proliferation with by standardizing on USB-C, and routed 3-phase power most homes. Oh, and the metric system. And while Europe has a wide range of cultures and functionality of government, a lot of places have simpler tax forms and a more prescriptive legal system (as opposed to the precedent-dominated Common Law tradition in the US). The German-speaking countries even rewrote spelling to make it simpler.
I view a lot of this stuff as infrastructure investment. We shouldn't have to stumble over the mundane to do interesting things. As others have commented, Europe also had the advantage of adopting some technologies later, but in some cases they just seem to be more aligned with a system of constant (if sometimes frustratingly slow) improvement.
Three-phase power is really about delivering more power with less copper by 1) sharing the neutral conductor (or getting rid of it) and 2) using lower currents which can make do with much thinner conductors.
The difference between one three-phase feeder and three completely separate two-wire circuits is that the three phases, which are 120° apart, share a single neutral conductor. In fact, if the load is perfectly balanced across the phases and currents are sine waves, they will cancel each other out, so neutral will carry no current at all and can be omitted! But in practice, there still usually is a neutral conductor to carry the imbalance (except for specific loads like certain delta and star motors). In total, we only need 4 wires instead of 6 to carry the same amount of power. That's 1/3 less copper! (Excluding PE of course.)
Now, compared to using a single two-wire circuit rated for three times the current, three-phase also wins by a long shot. (We're again assuming a balanced load and equal power factors.) This is because resistive heat scales with the current squared, so 3 times the current produces 9 times the amount of heat at the same resistance. So, we need to use thicker conductors to lower the resistance. But the area of its cross-section grows quicker than the surface area to dissipate heat, so the maximum current a conductor can safely carry scales sublinearly with its cross-sectional area. For example, 1.5mm² will suffice under most conditions to carry 16A, but for 48A we'll typically need 10mm².
All in all, the rule of thumb is that three-phase AC gets you the same amount of power for roughly 25% less copper compared to single-phase AC!
Some loads also make use of the rotating magnetic field, like motors (see below).
Lastly, lower currents will reduce heating in case of loose connections, so it might even be safer. On the other hand, a 400V phase-to-phase shock is more severe than a 230V phase-to-neutral shock.
Common use cases (load-side):
- Motors. Three phases produce a rotating magnetic field, perfect for simple self-starting motors. (Arguably, this is less relevant today with more modern motor designs, though three-phase induction motors are still widely used.)
- Electric cookers (usually split by cooking zones and oven, like one phase for two zones each, and the third phase for the oven)
- Water heaters (especially those that heat water instantaneously on demand)
- EV charging (even an ancient European three-phase installation is likely able to deliver 11kW of power and can therefore fully charge an EV overnight)
I would agree the plugs are well designed, but it’s also a space pen when you needed a pencil. Using that massive plug and 240V to charge a phone or power a light bulb is just comical.
The US system sensibly uses 110-120V for most uses and then 240V where it really matters.
Well, you don't need to use that 'massive' plug to charge your phone....usb sockets are a thing. And the lights in my house don't have any plugs on them.
I used to think this, but I've been in the US just long enough to start rethinking it. The one thing I still prefer though is that each outlet has an off switch, no need to unplug your cable. Also, three prong cables are 90 degrees offset so it's easier to fit behind furniture.
At least in France,those sorts of 10A power strips are not sold I'm pretty sure. (in reputable stores). Especially not a design like that where to allows to plug devices that need an earth into it. Id almost suspect that your link is also a china special that somehow doesn't have safety certification..
But in France, the 16A shuko outlets are on a max 20A breaker, which means you can still overload a 16A power strip, but I guess there's enough margin there that the regulator considers that to be OK.
Although at least at my work we had someone come in and replace all the power strips with ones that have a 16A resettable breaker thing built in. So maybe I'm commercial spaces it's different.
> I'm typically not a big EU defender but it's one of the thing that is really oh-so-much better in the EU: every time I go to the US having to plug stuff into electrical outlet feels like I've been beamed back to the 1950s or something. Plugs don't fit properly: they simply feel loose.
IIRC, the US electrified first. So a lot of its standards are kinda the first attempt, but they've stuck because the switching costs are too great. Other countries had the benefit of being able to improve on an existing system.
But I'm not sure if that really applies to plugs (IIRC British [giant] and Japanese [no grounding] ones are worse). But my understanding is the US 110v thing is kinda limiting, and 220v is way better.
> Plugs don't fit properly: they simply feel loose.
Let me guess: it was in a hotel? Hotel plugs are shit and worn out, because they get used far more heavily than pretty much anywhere else.
> Or you need to use super bulky, non-sensical, plugs.
For what? The only bulky US plugs are for weird things like dryers and electric ovens.
Along those same lines, I still don't really understand why so many people call it 110v and 220v when the US hasn't been those voltages for around 100 years and it's been 120v and 240v for about 60 years (it was gradually stepped up the voltage starting in the 1930s).
> But my understanding is the US 110v thing is kinda limiting, and 220v is way better.
120V is safer (not "safe", "safer"[1]) than 240V. And for the times when 240V (or 208V) is a better fit, we have that available to us relatively easily.
> For what? The only bulky US plugs are for weird things like dryers and electric ovens.
Or the locking plugs, but I think that still fits your point: These are high-voltage and/or high-current things, which aren't being unplugged/plugged too much.
Japanese electrical is better than the US. We have insulated pin sleeves so kids can't touch electrified pins and whole-home GFCI. The standard wall switches are also so much nicer.
Curious why you’d need/want whole home gfi. I’m assuming that means that if there’s a short on any circuit power to the entire house is cut? GFI outlets provide a very localized layer of safety and because they are localized can be extraordinarily sensitive. Like trip with a small amount of condensation on a wire.
I can't talk about Japan, but in the European installations that I'm familiar with, all general-use circuits are also protected with RCD (GFCI).
> Curious why you’d need/want whole home gfi
Because the danger they protect against is not confined to bathrooms and the outdoors!
An RCD (GFCI) trips quickly when there is an imbalance between outgoing and returning current exceeding a certain threshold, indicating that some current is likely leaking to earth. A little more than 30mA AC through the body sustained for a couple of seconds can kill someone, but is not enough to trip a regular circuit breaker!
Wetness increases conductivity and therefore the risk of a dangerous electric shock, but a faulty appliance or damaged cable elsewhere exposing you to mains voltage can be life-threatening too!
So, why shouldn't we protect the entire house?
> I'm assuming [...] if there’s a short on any circuit power to the entire house is cut
Small nitpick: a GFCI/RCD doesn't trip because of a line-to-neutral short circuit, it only trips if some current "escapes" to somewhere else. Though it is true that nowadays we often install RCBOs which combine residual-current, overload, and short-circuit protection.
But your concern about nuisance trips is somewhat justified. If there is really only one RCD serving the entire house, which is very common for older installations, a ground fault will cause a larger outage.
Newer installations, however, typically use multiple RCBOs to reduce the blast radius. And really old installations, where small current leaks are more common, might not have an RCD anyway.
Also, in my experience, it's just not a problem in practice. I can count the number of nuisance RCD trips I've had in my life on one hand. And genuine faults are similarly rare. Other kinds of power outages are far more common.
> GFI outlets provide a very localized layer of safety [...] can be extraordinarily sensitive
I fully agree that this is an advantage.
A standard 30mA RCD or RCBO, as would be installed in Europe, should disconnect within 40ms at 150mA, but might take longer at lower currents. That could still be quite a substantial electrical shock. (I'm not qualified to say exactly how dangerous it still is, but I can attest to the fact that it can still hurt pretty bad even if the RCD trips.) A 5mA GFCI, as is typical in the US, provides a much larger safety margin. I guess nuisance trips would be a much bigger problem if the detection threshold for RCDs was lowered to 5mA.
So maybe we can agree that the perfect solution would be to have GFCI outlets everywhere?
Because as it stands, you either have crude protection everywhere, or good protection limited to a few outlets.
One last note: Whether you have GFCI outlets or RCDs in your electrical panel, make sure to test them regularly via the test button! A faulty protection is no protection, and it's better to be safe than sorry.
> So maybe we can agree that the perfect solution would be to have GFCI outlets everywhere?
Meh, gfci outlets aren’t that expensive so if you’re a super vigilant home owner you could easily put one on every circuit in your house. But modern code calls for them in the laundry room, garage, bathrooms and kitchen, so for all practical purposes you almost do have them on every circuit.
For the whole house or circuit, that’s exactly what breakers are for.
For the risk of shock from an electrified appliance, that’s what the ground is for and is a very reliable solution provided that it’s actually done correctly. Unfortunately a lot of builders and electricians cut corners and either don’t ground or don’t do it properly.
To me seems like people are hating on a pretty great system. Put differently, if all you had was a whole house GFCI and someone invented an outlet GFCI that enabled localized fault detection at very low levels it would seem like an advancement. Funny to hear people want to go backwards.
I've got AFCI/GFCI breakers on every circuit in my house, in the US. Had to get a service upgrade anyway, and the added cost wasn't huge compared to that, so I had them upgrade all the breakers. 0 nuisance trips since then.
> For the risk of shock from an electrified appliance, that’s what the ground is for
Ground does not protect against every shock hazard! Devices can fail in many ways where live parts are exposed without contacting the grounded casing. Also, imagine a little child poking a metal stick into the outlet. Now you'd better hope that outlet has GFCI. Modern code does not call for it in a child's bedroom, does it?
Edit: To be fair, modern receptacles should be tamper-resistant, but then imagine a child reaching into a lightbulb socket, or cutting through a wire, or the insulation on a wire becoming damaged, etc. pp.
> for all practical purposes you almost do have [GFCI] on every circuit
But there are still gaps! I got shocked by an old clothes iron once (and I'm glad it tripped the RCD at the panel). Bedrooms and living rooms can have electrical faults too!
Another advantage of RCD at the panel is that it protects all downstream parts of the panel and all circuit wiring too! A lot of fatalities come from people working on live wiring. (In fact, many electrocution deaths are electrical contractors.) Now sure, they almost certainly weren't following correct safety procedures, but still, a lot of them could have been saved by an RCD. Some people probably die changing their light bulbs. That's preventable by installing an RCD at the panel, so that the entire circuit is protected, not just everything plugged into a GFCI outlet.
> To me seems like people are hating on a pretty great system. [...] localized fault detection [...] would seem like an advancement
I agree that localized fault detection, all else being equal, is an advancement. But if it comes at the cost of no GFCI protection at all on other circuits, I'm not sure it's worth the tradeoff.
Hundreds of people in the US die every year from low voltage electrical shocks. This number used to be a lot higher before GFCI was common, but it likely could be lower still if GFCI was required everywhere.
Obviously it would be best to have broad coverage and localized tripping, but if I had to pick one, I'd choose broad coverage. Calling it "going backwards" misses the concern of how much is protected, rather than just how localized the impact is when there is a fault.
It trips whenever hot wire gets exposed and touched by anything other than return wire. So basicaly it protects against any failure of insulation of the hot wire. At the latest when you come in contact with it in any manner.
Ground is pretty useless these days where 90% of the things we plug in are just DC adapters that don't use it. GFCI is more useful at detecting the faults that matter. Ground makes sense for your major appliances with metal cases and Japan has always had ground in kitchen/laundry.
The US plug is uniquely bad in that you can have live contacts exposed on a partially plugged in plug
I'd call both the British and the Schuko better. But they both come with tradeoffs. The British plug is huge, in part because of the built-in fuse. The Schuko is aesthetically less clean because the outlet is not flush, and because the plug is reversible you can't design around polarity. Both excellent plugs that are huge improvements over the US plug design in most ways, but both come with their own tradeoffs
British and Schuko are both relatively huge. Even the 2-prong europlug that small electronics use, that also can be installed in a Schuko outlet, often make the European version of things like usb-c chargers significantly larger than the US version. I live in Europe but travel a lot. For all small electronics I try to get a Japanese or US version, and then use a small adapter. For travel, a US usb-c charger plus EU adapter is smaller than an EU usb-c charger plus US adapter. British-style outlets can also be coaxed to take a europlug, not that I would advise anyone to do that.
You can get some nifty fold-flat BS1363 doodads, though. I have a USB-C charger that collapses into something about the size of a stack of 6 credit cards. Something similar is currently available as the "Galvanox Flat USB-C Charger" on Irish Amazon.
My international travel "brick" for laptop + phone is an Anker PowerPort Atom III Slim, which is flat multi-port charger with an IEC-320-C8 input. For the Continent, I plug in a "0cm cable" that's a Europlug nub. For US and UK/I, a NEMA cord with a compact BS1363 "shaver adapter" with a 1A fuse in it. Really wish I could get something flatter to be the adapter! Maybe I'll have to make one.
That is pretty nifty. I used an Anker A2669 for travel within the UK, a bit chunkier but also with folding pins.
I appreciate that they seem to put some effort into the design of their UK only products, instead of just shipping a US/Cn shaped charger with a BS1363 plug grafted on
>The US plug is uniquely bad in that you can have live contacts exposed on a partially plugged in plug
Most people in the US will go their whole lives without having an issue related to this or knowing anyone who did. This is one of those problems that mostly only exists as a post-hoc justification for an already held belief.
The typical outlet is not GFCI protected just due to the math of volume of new construction vs old construction vs service life. We're probably close to 50% coverage in new builds, more in low room count/wall area apartments.
>>> The US plug is uniquely bad in that you can have live contacts exposed on a partially plugged in plug
> Yeah until you have kids. Before GFCI were a code requirement, electrical incidents were a constant source of injuries and fatalities.
Isn't GFCI only required in wet areas (e.g. kitchen and bathroom)? And even if they're not more widely required, code requirements aren't retroactive, so I'd imagine the vast majority of houses will be missing GFCI from a large number of outlets.
in Germany we require GFCI everywhere for decades now. In wet rooms it has been required since 1984, in outlets since 2009.
Austrian electrical code is even more strict, every time a renter changes or the home is sold, electrical wiring has to be brought fully up to current code.
> the US 110v thing is kinda limiting, and 220v is way better
More efficient with copper certainly, but 110V is safer: cf. Ohm's Law. Lower voltage penetrates skin less readily, so you're more likely to escape unscathed from a 110V zap.
In Ireland, on worksites, the corded tools are 110VAC/50Hz (115V, 120V... mains/2 on a transformer-- and 'mains' varies wildly according to my several years of data captures in a range between 214-240).
Speaking of copper efficiency, the British Isles do all kinds of silly things like running ring mains to enable the use of smaller conductors for higher loads on domestic electrical sockets, and notionally to provide a safety factor.
Being safer might've helped cut costs and speed up electrification 100yr ago. These days I think it's greatly nerf'd by all the relevant bits of industry and government being dominated by do-gooders who think you need to be triple licensed and wear a bomb squad suit to install a ceiling fan and business interests who want a pretext to sell more stuff.
US plugs & sockets optionally have all of those features. And the fuse in the plug is because the UK allowed ring circuits, which cause house fires if the individual appliances aren't fused. It only blows if the appliance has already drawn too much current, which almost always means the appliance already has a fault.
Yes, that is the intended purpose of the fuse - To stop a faulty appliance drawing excessive current and starting a fire.
The benefit of the per appliance fuse is that a 3A appliance can have a 3A fuse, rather than the full 13A the socket is rated to provide. No difference for a dead short, but easily the difference between fire and no fire for a stalled motor.
Can I ask why you think a ring main is more likely to cause a fire if overloaded? I think this could be a misconception, but I'm curious to hear your thoughts
> * But my understanding is the US 110v thing is kinda limiting, and 220v is way better.*
You can have 240V for any plug in the house in the US: install a double-pole breaker at one end, and a NEMA 6 plug at the other.
The US uses 240V in a number of situations: it's used for kitchen ranges, clothes dryers, external AC/HP units, and recent EV charging. Are there other places where it's needed? (Personally I wouldn't mind having it for tea kettles.)
But how many other applications need >2000W of power delivery that 220V would allow?
> But how many other applications need >2000W of power delivery that 220V would allow?
Tea kettles, space heaters, some power tools (e.g. I've got an electric power washer that uses like 14A, and it was too weak to run an attachment I'd hoped to use with it.).
Also, I think countries that have 220V at the wall have access to 440V for when Americans would use 240V, so they can have even faster EV chargers, etc.
one of my favorite YT channels together with Technology Connections (though as was mentioned recently, the videos are a bit on the longer side, but I like the form anyway), anything else similar?
unrelated to 1st paragraph - I like as well Mustard, B1M, Wendover Productions
This is not a US electrical outlet, but it's one I've recently become aware of, which folks might find interesting:
Our next data center, for the HPC portion, may end up getting 480 VAC to the rack, with each outlet getting 277 VAC (one phase plus neutral and ground). If you order a generic Dell server, you'll find they now have power supply options for 277VAC.
What's the outlet? The D-Grid 400 (SDG 400). So, there's another outlet to add to the list!
Since 1996, the NEMA 10 column (10-20, 10-30) is no longer allowed in new installations.
That was, for decades, the standard dryer outlet. No ground. The frame of the dryer is grounded to the neutral! Not to protective ground.
This is idiotic by modern standards, but is still found in older houses.
(Haven't had to look at the NEMA outlet chart in years. I once had to specify a computer room back when DEC was a company. DEC used about five different connectors - some 110V, some 220V, some 3-phase, various current ratings.
Needed custom-fabricated raceways with all the correct outlets.
Plus the
electrical people at the aerospace company insisted on putting a hulking big copper busbar tied to ground on top of each raceway, and all cabinets were grounded to that.
That was to give RF noise a very low resistance path to ground. Much RF R&D took place in that building, and things which blithered all over the RF spectrum were seriously annoying to the RF engineers. Computer grounding used to be a big deal, before everybody started using differential signals for almost everything.)
>Since 1996, the NEMA 10 column (10-20, 10-30) is no longer allowed in new installations. That was, for decades, the standard dryer outlet. No ground. The frame of the dryer is grounded to the neutral! Not to protective ground. This is idiotic by modern standards, but is still found in older houses.
The way those old outlets work is you get two hots and a ground. No neutral. This is fine for simple appliances that run wholly on 220v and utilize mechanical controls (so like all old appliances) but as you start adding complexity in the appliance you start wanting to use 120v control circuitry stuff (i.e. a cost saving hack by the device manufacturer) and this opens the door for the appliance to be live at 120v if the case is bonded to the ground and your ground wire in the cord is broken. Or it opens the door for the case of the appliance to be floating and live at 120v if there's a short to it.
With appliances manufactured for global markets these days that accept all manner of input voltages and run any controls off of some DC powered circuit board this isn't really a problem anymore but with the way people worship rules like religion I'm sure in the year 3026 we'll still be reading comments like yours.
No, they're two hots with 240V between them, and a neutral, 120V to each hot. No protective ground. See [1]. The neutral is grounded, but usually back at the pole transformer.
Protective ground is never supposed to carry current unless there's a fault.
The neutral in a 3-prong dryer plug is the return for the 120V motor, so it carries current.
I've had an open neutral on my house. A tree slowly grew enough to take out the drop to the house, and it broke the neutral first. The computers were fine but smoke came out of the washing machine, which saw overvoltage.
You're gonna have to tell that to the literally millions of houses that have a dryer/range plugged into a 10-50 that's fed off a BX cable with two conductors in it (which of course leads back to a grounded panel). I'm not saying it's right, but if it didn't work all those houses wouldn't still have it in service. I mean let's be real here 99% of the time it's just running a timer or a clock, not anything with serious amperage.
The most common way to install the NEMA 5-15 outlets is vertically, with the two slots above and the round ground pin below. However, in the building where I live, while most outlets are installed that way, the outlets that are controlled by a wall switch are installed "upside-down", with the ground pin at the top which makes it easier to tell which are switched and which are not.
Also, I have noticed that at the (very large) medical center where all my doctors are, all outlets are installed "upside-down". These are the regular outlets where things like PCs are plugged in, and is true both in new and in very old buildings. Anyone have any idea why they would do that?
I don't know the answer but I think the "upside down for switched control" is clever.
When I rented a house, I went through and tested every outlet, light and switch and labeled them documenting their control and circuit. It seems like that should be standard for homes when they're built.
The upside down installation in hospitals came up a few weeks ago and if I recall correctly, the reason was that if a large metal object were to fall on the plug, falling on the ground pin things are okay, but if it falls the power prongs things are not okay.
So, ground side up is usually safer.
I do not recall hearing a explanation of why the US naturally installs things to be more dangerous.
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[ 0.22 ms ] story [ 63.6 ms ] threadThat and switches (like light switches): not only we've got way more variety in the EU but they also all feel of better quality.
Both electrical outlets and switches in the US do also look old and dated. Just like they feel when using them: old and outdated.
It's just all really weird, nearly anachronistic.
So, when I arrived in Barcelona and Catalonia, I was pleasantly, mildly surprised that not only had Europe kept pace with us techno-mages in America, but they had some kind of parallel evolution going on, in terms of connectors, interfaces, protocols, etc.
My fiancée was sort of mystified, because my favorite subject of photography was not landmarks or her pretty face, but the circuit breaker box, the rear of her television set, the A/C unit, and any other cool, distinctly Euro-tech instances I could identify around there.
I tried helping her adjust/fix her aerial TV antenna, got zapped a few times; discovered that Catalonian TV antennas are energized with a few volts for whatever reason; decided that Euro-tech is beyond my expertise to tinker with on someone else's behalf, especially a native family.
Thankfully, I didn't have any portable electronics or appliances in my luggage that needed adapters or plugs, but the experience was truly humbling, and eye-opening, and I returned to the United States with a better calibrated worldview.
Competitively the US does well in energy tech and agriculture tech. The US is #2 in wind power, #2 in solar power, #1 in nuclear power, along with being the world's biggest oil & natural gas producer. The US industrial rail system is also an epic scale marvel, while its consumer rail system is pathetic.
It's definitely not elite in most infrastructure (including electrical plugs).
If you were than combined figures put USA behind places like Germany and Spain.
And bringing nuclear into it you get France absolutely trouncing.
So your argument is that “america is a big country”.
Meanwhile Europe standardized bank transfers with IBAN, killed connector type proliferation with by standardizing on USB-C, and routed 3-phase power most homes. Oh, and the metric system. And while Europe has a wide range of cultures and functionality of government, a lot of places have simpler tax forms and a more prescriptive legal system (as opposed to the precedent-dominated Common Law tradition in the US). The German-speaking countries even rewrote spelling to make it simpler.
I view a lot of this stuff as infrastructure investment. We shouldn't have to stumble over the mundane to do interesting things. As others have commented, Europe also had the advantage of adopting some technologies later, but in some cases they just seem to be more aligned with a system of constant (if sometimes frustratingly slow) improvement.
What is the advantage to this? Are there use cases for using all three phases (in one appliance?)?
The difference between one three-phase feeder and three completely separate two-wire circuits is that the three phases, which are 120° apart, share a single neutral conductor. In fact, if the load is perfectly balanced across the phases and currents are sine waves, they will cancel each other out, so neutral will carry no current at all and can be omitted! But in practice, there still usually is a neutral conductor to carry the imbalance (except for specific loads like certain delta and star motors). In total, we only need 4 wires instead of 6 to carry the same amount of power. That's 1/3 less copper! (Excluding PE of course.)
Now, compared to using a single two-wire circuit rated for three times the current, three-phase also wins by a long shot. (We're again assuming a balanced load and equal power factors.) This is because resistive heat scales with the current squared, so 3 times the current produces 9 times the amount of heat at the same resistance. So, we need to use thicker conductors to lower the resistance. But the area of its cross-section grows quicker than the surface area to dissipate heat, so the maximum current a conductor can safely carry scales sublinearly with its cross-sectional area. For example, 1.5mm² will suffice under most conditions to carry 16A, but for 48A we'll typically need 10mm².
All in all, the rule of thumb is that three-phase AC gets you the same amount of power for roughly 25% less copper compared to single-phase AC!
Some loads also make use of the rotating magnetic field, like motors (see below).
Lastly, lower currents will reduce heating in case of loose connections, so it might even be safer. On the other hand, a 400V phase-to-phase shock is more severe than a 230V phase-to-neutral shock.
Common use cases (load-side):
- Motors. Three phases produce a rotating magnetic field, perfect for simple self-starting motors. (Arguably, this is less relevant today with more modern motor designs, though three-phase induction motors are still widely used.)
- Electric cookers (usually split by cooking zones and oven, like one phase for two zones each, and the third phase for the oven)
- Water heaters (especially those that heat water instantaneously on demand)
- EV charging (even an ancient European three-phase installation is likely able to deliver 11kW of power and can therefore fully charge an EV overnight)
The US system sensibly uses 110-120V for most uses and then 240V where it really matters.
And... the plug really isn't that big at all.
But in France, the 16A shuko outlets are on a max 20A breaker, which means you can still overload a 16A power strip, but I guess there's enough margin there that the regulator considers that to be OK.
Although at least at my work we had someone come in and replace all the power strips with ones that have a 16A resettable breaker thing built in. So maybe I'm commercial spaces it's different.
IIRC, the US electrified first. So a lot of its standards are kinda the first attempt, but they've stuck because the switching costs are too great. Other countries had the benefit of being able to improve on an existing system.
But I'm not sure if that really applies to plugs (IIRC British [giant] and Japanese [no grounding] ones are worse). But my understanding is the US 110v thing is kinda limiting, and 220v is way better.
> Plugs don't fit properly: they simply feel loose.
Let me guess: it was in a hotel? Hotel plugs are shit and worn out, because they get used far more heavily than pretty much anywhere else.
> Or you need to use super bulky, non-sensical, plugs.
For what? The only bulky US plugs are for weird things like dryers and electric ovens.
120V is safer (not "safe", "safer"[1]) than 240V. And for the times when 240V (or 208V) is a better fit, we have that available to us relatively easily.
> For what? The only bulky US plugs are for weird things like dryers and electric ovens.
Or the locking plugs, but I think that still fits your point: These are high-voltage and/or high-current things, which aren't being unplugged/plugged too much.
[1]: https://youtu.be/jMmUoZh3Hq4?si=JyZIge5lQXda4D0E&t=811
But those are the situations where we then use 3-phase 400V
> Curious why you’d need/want whole home gfi
Because the danger they protect against is not confined to bathrooms and the outdoors!
An RCD (GFCI) trips quickly when there is an imbalance between outgoing and returning current exceeding a certain threshold, indicating that some current is likely leaking to earth. A little more than 30mA AC through the body sustained for a couple of seconds can kill someone, but is not enough to trip a regular circuit breaker!
Wetness increases conductivity and therefore the risk of a dangerous electric shock, but a faulty appliance or damaged cable elsewhere exposing you to mains voltage can be life-threatening too!
So, why shouldn't we protect the entire house?
> I'm assuming [...] if there’s a short on any circuit power to the entire house is cut
Small nitpick: a GFCI/RCD doesn't trip because of a line-to-neutral short circuit, it only trips if some current "escapes" to somewhere else. Though it is true that nowadays we often install RCBOs which combine residual-current, overload, and short-circuit protection.
But your concern about nuisance trips is somewhat justified. If there is really only one RCD serving the entire house, which is very common for older installations, a ground fault will cause a larger outage.
Newer installations, however, typically use multiple RCBOs to reduce the blast radius. And really old installations, where small current leaks are more common, might not have an RCD anyway.
Also, in my experience, it's just not a problem in practice. I can count the number of nuisance RCD trips I've had in my life on one hand. And genuine faults are similarly rare. Other kinds of power outages are far more common.
> GFI outlets provide a very localized layer of safety [...] can be extraordinarily sensitive
I fully agree that this is an advantage.
A standard 30mA RCD or RCBO, as would be installed in Europe, should disconnect within 40ms at 150mA, but might take longer at lower currents. That could still be quite a substantial electrical shock. (I'm not qualified to say exactly how dangerous it still is, but I can attest to the fact that it can still hurt pretty bad even if the RCD trips.) A 5mA GFCI, as is typical in the US, provides a much larger safety margin. I guess nuisance trips would be a much bigger problem if the detection threshold for RCDs was lowered to 5mA.
So maybe we can agree that the perfect solution would be to have GFCI outlets everywhere? Because as it stands, you either have crude protection everywhere, or good protection limited to a few outlets.
One last note: Whether you have GFCI outlets or RCDs in your electrical panel, make sure to test them regularly via the test button! A faulty protection is no protection, and it's better to be safe than sorry.
Meh, gfci outlets aren’t that expensive so if you’re a super vigilant home owner you could easily put one on every circuit in your house. But modern code calls for them in the laundry room, garage, bathrooms and kitchen, so for all practical purposes you almost do have them on every circuit.
For the whole house or circuit, that’s exactly what breakers are for.
For the risk of shock from an electrified appliance, that’s what the ground is for and is a very reliable solution provided that it’s actually done correctly. Unfortunately a lot of builders and electricians cut corners and either don’t ground or don’t do it properly.
To me seems like people are hating on a pretty great system. Put differently, if all you had was a whole house GFCI and someone invented an outlet GFCI that enabled localized fault detection at very low levels it would seem like an advancement. Funny to hear people want to go backwards.
Ground does not protect against every shock hazard! Devices can fail in many ways where live parts are exposed without contacting the grounded casing. Also, imagine a little child poking a metal stick into the outlet. Now you'd better hope that outlet has GFCI. Modern code does not call for it in a child's bedroom, does it?
Edit: To be fair, modern receptacles should be tamper-resistant, but then imagine a child reaching into a lightbulb socket, or cutting through a wire, or the insulation on a wire becoming damaged, etc. pp.
> for all practical purposes you almost do have [GFCI] on every circuit
But there are still gaps! I got shocked by an old clothes iron once (and I'm glad it tripped the RCD at the panel). Bedrooms and living rooms can have electrical faults too!
Another advantage of RCD at the panel is that it protects all downstream parts of the panel and all circuit wiring too! A lot of fatalities come from people working on live wiring. (In fact, many electrocution deaths are electrical contractors.) Now sure, they almost certainly weren't following correct safety procedures, but still, a lot of them could have been saved by an RCD. Some people probably die changing their light bulbs. That's preventable by installing an RCD at the panel, so that the entire circuit is protected, not just everything plugged into a GFCI outlet.
> To me seems like people are hating on a pretty great system. [...] localized fault detection [...] would seem like an advancement
I agree that localized fault detection, all else being equal, is an advancement. But if it comes at the cost of no GFCI protection at all on other circuits, I'm not sure it's worth the tradeoff.
Hundreds of people in the US die every year from low voltage electrical shocks. This number used to be a lot higher before GFCI was common, but it likely could be lower still if GFCI was required everywhere.
Obviously it would be best to have broad coverage and localized tripping, but if I had to pick one, I'd choose broad coverage. Calling it "going backwards" misses the concern of how much is protected, rather than just how localized the impact is when there is a fault.
It trips whenever hot wire gets exposed and touched by anything other than return wire. So basicaly it protects against any failure of insulation of the hot wire. At the latest when you come in contact with it in any manner.
I'd call both the British and the Schuko better. But they both come with tradeoffs. The British plug is huge, in part because of the built-in fuse. The Schuko is aesthetically less clean because the outlet is not flush, and because the plug is reversible you can't design around polarity. Both excellent plugs that are huge improvements over the US plug design in most ways, but both come with their own tradeoffs
See also: https://plugsocketmuseum.nl/GB-foldingPlug1.html
My international travel "brick" for laptop + phone is an Anker PowerPort Atom III Slim, which is flat multi-port charger with an IEC-320-C8 input. For the Continent, I plug in a "0cm cable" that's a Europlug nub. For US and UK/I, a NEMA cord with a compact BS1363 "shaver adapter" with a 1A fuse in it. Really wish I could get something flatter to be the adapter! Maybe I'll have to make one.
I appreciate that they seem to put some effort into the design of their UK only products, instead of just shipping a US/Cn shaped charger with a BS1363 plug grafted on
I tried that once and the fit was so tight I thought I'd break both the plug and the outlet.
Most people in the US will go their whole lives without having an issue related to this or knowing anyone who did. This is one of those problems that mostly only exists as a post-hoc justification for an already held belief.
> Yeah until you have kids. Before GFCI were a code requirement, electrical incidents were a constant source of injuries and fatalities.
Isn't GFCI only required in wet areas (e.g. kitchen and bathroom)? And even if they're not more widely required, code requirements aren't retroactive, so I'd imagine the vast majority of houses will be missing GFCI from a large number of outlets.
Austrian electrical code is even more strict, every time a renter changes or the home is sold, electrical wiring has to be brought fully up to current code.
More efficient with copper certainly, but 110V is safer: cf. Ohm's Law. Lower voltage penetrates skin less readily, so you're more likely to escape unscathed from a 110V zap.
In Ireland, on worksites, the corded tools are 110VAC/50Hz (115V, 120V... mains/2 on a transformer-- and 'mains' varies wildly according to my several years of data captures in a range between 214-240).
Speaking of copper efficiency, the British Isles do all kinds of silly things like running ring mains to enable the use of smaller conductors for higher loads on domestic electrical sockets, and notionally to provide a safety factor.
But in all seriousness they are comprehensively safer. The earthing and exposed live benefits are shared by most EU plugs, but as a bonus you've got:
- Built in fuse that can be sized to the appliance, not the socket
- Sliding gates on live and neutral that stop your 5 year old jamming a fork in there
- The gate is moved by the earth pin, ensuring it's long enough to make first contact
- An internal wiring arrangement that avoids floating the whole appliance at live if a cable is forcibly ripped out
Yes, it's a bit bigger but I can't recall this having caused even one dead child worth of inconvenience across my life.
They are however, even worse than Lego to step on in the night. I'll concede that as their one true weakness
It's nice that they're mandatory though.
Yes, that is the intended purpose of the fuse - To stop a faulty appliance drawing excessive current and starting a fire.
The benefit of the per appliance fuse is that a 3A appliance can have a 3A fuse, rather than the full 13A the socket is rated to provide. No difference for a dead short, but easily the difference between fire and no fire for a stalled motor.
Can I ask why you think a ring main is more likely to cause a fire if overloaded? I think this could be a misconception, but I'm curious to hear your thoughts
You can have 240V for any plug in the house in the US: install a double-pole breaker at one end, and a NEMA 6 plug at the other.
The US uses 240V in a number of situations: it's used for kitchen ranges, clothes dryers, external AC/HP units, and recent EV charging. Are there other places where it's needed? (Personally I wouldn't mind having it for tea kettles.)
But how many other applications need >2000W of power delivery that 220V would allow?
Tea kettles, space heaters, some power tools (e.g. I've got an electric power washer that uses like 14A, and it was too weak to run an attachment I'd hoped to use with it.).
Also, I think countries that have 220V at the wall have access to 440V for when Americans would use 240V, so they can have even faster EV chargers, etc.
Did anyone say Schuko?
unrelated to 1st paragraph - I like as well Mustard, B1M, Wendover Productions
Our next data center, for the HPC portion, may end up getting 480 VAC to the rack, with each outlet getting 277 VAC (one phase plus neutral and ground). If you order a generic Dell server, you'll find they now have power supply options for 277VAC.
What's the outlet? The D-Grid 400 (SDG 400). So, there's another outlet to add to the list!
(Haven't had to look at the NEMA outlet chart in years. I once had to specify a computer room back when DEC was a company. DEC used about five different connectors - some 110V, some 220V, some 3-phase, various current ratings. Needed custom-fabricated raceways with all the correct outlets.
Plus the electrical people at the aerospace company insisted on putting a hulking big copper busbar tied to ground on top of each raceway, and all cabinets were grounded to that. That was to give RF noise a very low resistance path to ground. Much RF R&D took place in that building, and things which blithered all over the RF spectrum were seriously annoying to the RF engineers. Computer grounding used to be a big deal, before everybody started using differential signals for almost everything.)
The way those old outlets work is you get two hots and a ground. No neutral. This is fine for simple appliances that run wholly on 220v and utilize mechanical controls (so like all old appliances) but as you start adding complexity in the appliance you start wanting to use 120v control circuitry stuff (i.e. a cost saving hack by the device manufacturer) and this opens the door for the appliance to be live at 120v if the case is bonded to the ground and your ground wire in the cord is broken. Or it opens the door for the case of the appliance to be floating and live at 120v if there's a short to it.
With appliances manufactured for global markets these days that accept all manner of input voltages and run any controls off of some DC powered circuit board this isn't really a problem anymore but with the way people worship rules like religion I'm sure in the year 3026 we'll still be reading comments like yours.
Protective ground is never supposed to carry current unless there's a fault. The neutral in a 3-prong dryer plug is the return for the 120V motor, so it carries current.
I've had an open neutral on my house. A tree slowly grew enough to take out the drop to the house, and it broke the neutral first. The computers were fine but smoke came out of the washing machine, which saw overvoltage.
[1] https://epicelectrical.com/3-prong-vs-4-prong-dryer-outlet/
Also, I have noticed that at the (very large) medical center where all my doctors are, all outlets are installed "upside-down". These are the regular outlets where things like PCs are plugged in, and is true both in new and in very old buildings. Anyone have any idea why they would do that?
When I rented a house, I went through and tested every outlet, light and switch and labeled them documenting their control and circuit. It seems like that should be standard for homes when they're built.
So, ground side up is usually safer.
I do not recall hearing a explanation of why the US naturally installs things to be more dangerous.