The reason plugs in the UK are so big is that each one must be individually fused. And the reason for that is something called a "ring circuit".
In a ring circuit you have, say, a 40 amp fuse at the mains/box. From this you send out two wires, each rated only for 20 amps, going in a circle around the house. You can now supply 40 amps worth of power using only cheaper 20 amp wires. (Since the current can flow over both wires at once.)
But this means that the wires going to an individual appliance are far too small for the main breaker, so each appliance gets a fuse in the plug.
Ring circuits have serious drawbacks, but they helped during a time when there was a copper shortage.
And ever since then the UK has been stuck with huge plugs.
They tend to rest on the plug's back, and hurt a lot when you step on them.
> Any other countries use them?
India and South Africa use the so-called Type D plug[0] (also called Type M in its 15A incarnation), which is similar but uses round plugs (type D is actually an older english standard). Some other south-east asian countries also use Type D. The english plug is called "Type G" and used in a number of former colonies and protectorates[1], especially in Africa and the Middle East.
I think that's simply so that the wire runs parallel to the wall instead of sticking out at 90 degrees. Without a movable part it's hard to have one feature without the other.
This is a common complaint. I wonder where people are leaving their unused plugs that they constantly tread on them? Probably not in a storage box/drawer.
The promo shots of the final working model don't show how you get at the fuse, but I'd be very surprised if it has been overlooked. I suspect it's something to do with the red dots.
> The promo shots of the final working model don't show how you get at the fuse, but I'd be very surprised if it has been overlooked. I suspect it's something to do with the red dots.
Indeed, the red dot is the plug cover. This set of blogspam pictures don't show it, but previous sets (the folding plug first made rounds in mid-2009) showed how the plug works. You can see an "action shot" simulation of the plug in the video: http://www.youtube.com/watch?v=f6DvjKkGT6s#t=1m46
Given a choice between US plugs (spark, fall out of sockets, flimsy, dangerous, bendy pins), and UK plugs (Built to last, don't spark, fused, solid) I know which I'd choose.
There's also large advantages to having each plug individually fused - individual appliances blow rather than the whole circuit.
So I wouldn't say we're "stuck with huge plugs". The only real time it's a slight issue/pain is when you go on a plane and the cables take up a bit of space.
Wow, so self-delusion is alive and well in the UK!
"The only time its a slight issue"???
How about manufacturing, shipping, selling, storing, repairing, and paying for that overdesigned eyesore? How about looking at it? How about moving the couch out from the wall so the dang thing will fit back there?
* trip up a cable, and the plug falls out of the wall
(Pulling a UK plug out required force. It will not pull out)
Plus the cable exits a plug pointing downward, which
means it will not pull out via the cable.
* Sparks when you put a plug in or out.
* Bent pins that look like they're about to drop off
* No shielding on pins
* Often no mechanism to stop things being put in sockets
(All UK sockets only open once an earth pin has gone in
I wonder what the incidence of electrocution is in the UK vs US. I'm probably biased, but I certainly feel far safer here, especially having kids.
Lamps seem very prevalent in the US. Why do most apartments I've been in not have ceiling lights? WTF? When I lived in the US I'd go in a room and spend a while finding 4 lamps and turning them on. Same in hotels.
Also, when you decide to put a lamp somewhere, you typically make sure the cable is not somewhere that can be tripped up.
But as I say, all rooms in the UK come with a fitted ceiling light, and a light switch by the door. So lamps are less common.
Even though I currently live in a U.S. apartment where the main rooms have no light fixtures (though they do have switched outlets), past experience hasn't shown a trend of not having light fixtures. Additionally, newer construction seems to have more fixtures, not less. This thread seems to be a circus of alternately overstating and understating problems though, so I'd take it with a huge grain of salt.
So you're saying that if you trip over the cord while your hair dryer is plugged into an American socket, it doesn't fall off of whatever ledge it's on? Do you use an industrial hair dryer or something?
Just FYI, the US NEC requires each entryway of a room in a dwelling to have a switch which can control a light.
It is usually, but does not have to be, an overhead light.
An alternative that is also code-conforming is to have the switch control a socket (typically, the bottom plug in several duplex receptacles in the room) where a lamp is plugged in. Sometimes people don't actually plug a lamp in there, so the switch does nothing, and maybe that's what you've been irritated by.
If the wiring is done this way -- e.g., bedrooms and living rooms -- it can be quite flexible if you want to rearrange the room layout. You move the furniture and plug the lamp into the bottom receptacle where-ever it is convenient and sensible.
> I wonder what the incidence of electrocution is in the UK vs US. I'm probably biased, but I certainly feel far safer here, especially having kids.
Cars kill 100 times more people than electrocution (not to mention severe injuries, which are rare for electrocutions), so they're probably a more important risk to worry about. Any slight difference in car accidents is going to swamp electrical concerns.
I just meant that as far as comparing the US to the UK for feeling safer (his words), electrocution concerns are pretty trivial. Unless he spends an unusual amount of time near wall sockets or suffers from an acute case of electrophobia.
> * trip up a cable, and the plug falls out of the wall
> (Pulling a UK plug out required force. It will not pull out)
> Plus the cable exits a plug pointing downward, which
> means it will not pull out via the cable.
This one is a mixed bag (trip up a cable, throw the expensive grandma lamp to the ground).
> * Sparks when you put a plug in or out.
Not at all. Euro plugs earth pin always makes contact first.
> * Bent pins that look like they're about to drop off
Bent pins? UK plugs are only marginally sturdier.
> * No shielding on pins
What use is it?
> * Often no mechanism to stop things being put in sockets
> (All UK sockets only open once an earth pin has gone in
All euro sockets have plastic spring-loaded linked stoppers that prevent accidental insertion of random stuff into the holes, and insertion of anything in only one hole (you need to push both sides together).
> The only real time it's a slight issue/pain is when you go on a plane and the cables take up a bit of space.
I prefer the UK plug too. But you missed one other very important point of pain: the pain of standing on one. As the flex on a UK plug leaves from the bottom, it has the unique property of tending to lay down on the floor with pins facing upwards.
When I was 14 years old, I went through a growth spurt and often passed out when I got up too quickly. One day, I got out of bed in a hurry, passed and and came to lying next to a broken (UK) plug, with a very sore head. It appeared that I had fallen head first onto the prongs of the upturned plug. Looking back, I was lucky not to have done myself a serious injury. A disadvantage of UK plugs versus those in other countries.
Why would the only choice to replace the huge UK plugs be US plugs? This one might make much more sense for example http://en.wikipedia.org/wiki/Schuko given the specs (much smaller, all the same advantages expect being fused - if I understand correctly) and also given the UKs geographic location ;)
The Schuko is definitely one of the better designs.
16A at 240V in a grounded plug that is very easy to protect against tiny fingers and that you'd have to be trying real hard to get your fingers on when inserting it, even in pitch dark.
Forwards compatible socket with the Euro plug. (that's the thin, ungrounded one with just two pins, one live, one neutral).
It will do anything from your phone charger to a light duty welder.
> Forwards compatible socket with the Euro plug. (that's the thin, ungrounded one with just two pins, one live, one neutral).
It's not really that it's forwards-compatible, but that the europlug was created specifically for this purpose. It's compatible with all european sockets but the english one I believe.
Edit: I'd just be happy if Europe picked a single standard and stuck with it. It's ridiculous to have to carry all sorts of converters for what are, in the grand scheme of things, not very long trips.
Yes, they do. Sometimes they'll even spark when they're just sitting there with something plugged in.
There is a mechanical/electrical machining process called spark erosion aka electrical discharge machining. Every time you have a spark a tiny bit of the metal of both contacts evaporates. Of course that's when you want it to happen, in sockets with plugged in loads you really don't want it to happen.
Over time this process accelerates and it has been the cause of many house fires in the US.
The fact that such sockets are placed in walls made of mostly wood placed right next to an upright stud does not help either.
Sometimes they're so bad you can actually smell the ozone.
Everything sparks - it's not unique to american plugs. In the UK the contact is just deeper so you can't see it. If anything UK plugs spark more because the voltage is higher.
And sparks are not the cause of many house fires, you just made that up. The sparks are harmless, and I've never seen a plug with erosion on it. Just because you can do it doesn't mean it actually happens.
No, I did not make that up, and I did not mean 'sparks on insertion' I meant 'sparks while inserted', though 'sparks on insertion' is not good either for your socket.
American plugs spark (much) more frequently and strongly than their equivalent UK/EU plugs because the spring pressure from the side contacts is insufficient to maintain good contact over the lifetime of an installation, especially if the plugs are also worn. The fact that typically the current is twice as high doesn't help either (though if you get zapped it's less of a problem than in 230V installations, the US uses a balanced 110 system for most residential circuits where only a few receptacles which are of a different design have both sides of the step-down transformer outside of the house running to them).
The UK/EU plugs are of a much more solid construction than the American ones, as are the wallsockets they go in to.
I've seen US sockets that made an audible buzz while operating and get extremely hot (hot enough to melt the plastic). Not good.
The usual way in which it gets to this state is that a socket has been overloaded a couple of times, or heavy load is plugged in or removed while switched on, the contacts have corroded or have some soot build up on them and then the resistance increases enough to start a runaway process that ends with the socket failing altogether or with the socket getting so hot that the plastic outside cover will start to melt.
At that point all bets are off, especially in houses that are mostly constructed from wooden sticks instead of brick or concrete.
Another cause of trouble like this is that there was a short period when due to the supply issues with copper electrical wire made of aluminum was tried in residential installations in the US.
These required special fixtures so the wire would not come lose as the aluminum compressed over time thus shrinking away from the contact and causing an airgap and thus sparking.
This kind of wiring is no longer 'code' and if you have such wiring it wouldn't harm to periodically tighten up on the screws to ensure good contact.
Aluminum oxide build-up compounds this problem.
People always blame 'short circuits' for electrical fires, but most of the time this is nonsense, since the breaker will almost always instantly trip in a short circuit situation. That's what they're designed to do.
Half shorts (shorts that are of a resistance low enough to cause significant heat build-up and high enough not to cause the breaker to trip) and faulty contacts (intermittent contacts, sparks and thus heat) are a much more frequent cause of fire.
Another big cause of fire is counterfeit junk hitting the market and do-it-yourself types that don't know the difference using this to wire up that extra socket for a space-heater in the attic.
You must deal mainly with very old poorly maintained houses (rentals?), because all those problems do not exist in normal outlets.
You have soot on your contacts???? Corrosion? Did it rain inside your house?
NEVER tighten aluminium contacts! You will cause exactly those problems that you describe. If there is a problem with it you need to remove it, apply the anti-oxidant paste and reinstall.
But aluminium to the contacts is very rare in america these days, where it does exists it's usually been pigtailed with copper.
> You must deal mainly with very old poorly maintained houses (rentals?), because all those problems do not exist in normal outlets.
Rural areas, farmhouses, but one building I lived in in Toronto had a problem (a bad one) with one of the sockets and it was a fairly recent upgrade from what I remember.
> You have soot on your contacts???? Corrosion? Did it rain inside your house?
No, simply an installation from the 70's still operating in 2005. There are millions like that. And I don't live there anymore, I'm back Europe now.
> NEVER tighten aluminium contacts!
Not over-tighten, tighten. You should do it to the proper torque (there are special tools for that).
> But aluminium to the contacts is very rare in america these days, where it does exists it's usually been pigtailed with copper.
Yes, that's the slightly newer method, also since outlawed (and used as a way to fix problems).
The biggest problem I think with the alu wiring was not even that it could not work, but that people would use it with the wrong connectors, the al specific sockets were pretty pricey.
The only place where I know that aluminum is still used in residential wiring is on the entrance wire from the pole to the transformer, usually that's a very tricky connector that uses wedges to make the contact.
If I found myself in a house with aluminum wiring I'd probably rewire the whole thing just for safety. Costly (especially with the US system which staples cables to studs) but worth the peace of mind.
No, I mean don't tighten it at all! Not unless you open it and add anti-oxidant. If you tighten it you break the air seal, and allow it to oxidize, and aluminium oxide does not conduct.
The correct installation uses anti-oxidant to seal it, then you tighten it enough to crack the aluminum oxide, and the anti-oxidant protects it. If you tighten it without fresh anti-oxidant you are creating a hazard.
And pig tails are not outlawed - quite the opposite, they are the recommended way to handle aluminium wiring.
> No, I mean don't tighten it at all! Not unless you open it and add anti-oxidant. If you tighten it you break the air seal, and allow it to oxidize, and aluminium oxide does not conduct.
Ah ok, I see what you mean now, yes that makes good sense.
As for the pigtails, as far as I know you can not make any new wiring with Aluminum in residential installations, pigtailed or not (I left my code book in Canada because it is of no use to me here, maybe there is some up-to-date online resource). Industrial use is still ok I believe.
I have visited the USA twice this year, and found the power outlets in expensive hotels, serviced apartments, and office buildings to be of a much lower build quality compared to those of my home country, Australia.
In my two months in the USA, I observed more arcs and electrical crackling noises than I have in the rest of my life in AU.
I'll add my anecdotal 2c :it's the same as you. The UK plug is overkill, IMO, but the US plug is downright nasty. The lack of 'off' switches in the majority of them is a problem. I always figured the problem stems from the original design, which was probably a version 1.0, as the USA was the first to get electricity into homes. That's why other countries have superior systems - they had time to learn from the problems and design better systems, with built-in grounds, isolating switches at the point, and higher voltages (220/240 vs 110).
But I could be all wrong, as I'm no expert beyond having a drawer full of adapter plugs.
Unfortunately yes. As a Brit living in America, every time I have to deal with a plug socket I feel ever so slightly like I'm about to electrocute myself. Sure, the big bulky plugs are a pain to carry around, but at least I felt safe using them.
Why not have socket fuses like you can find in bathrooms sometimes? I'm not arguing history, instead I'm just curious if there's some latent advantage to putting that hardware into the plug. All I can see are losses in convenience, duplication of effort, and weakened robustness.
Different plugs will have different fuses appropriate to the type of device. I have no idea how much of a benefit this is but you couldn't do that if the fuses were in the socket.
According to (http://www.faqs.org/faqs/electrical-wiring/part1/section-20....) and to the wiki article on wire gauges, 40A requires 8-gauge wire, which is 3.264mm in diameter, while 20A is 12-gauge, which is 2.054mm. The ratio of their cross-sectional area is 2.53; this justifies that the 40A wire conducts twice as much as the 20A but has 2.53 as much area, thus being more costly.
I'm not sure why. Is the skin effect sufficient to explain this?
Yes, a ring circuit you run a single wire around the room and back to the fuseboard. With a spur circuit you run a single wire to the furthest plug.
In a typical room going back to the fuseboard isn't much further so it's not twice as much wire - more like 10% more
There's also a second reason British plugs are robust and fused: they're built to carry up to 3 kilowatts at 230 volts. (None of your wimpish American 110 volt mains juice here! Nothing quite makes your hair stand on end like accidentally touching a live pin carrying 230 volts and 13 amps ...)
To that end, the live and neutral contacts in a British socket are shuttered. The long earth pin on the plug makes contact before the live or neutral pins are in the socket, and once in contact, raises a shutter to permit live and neutral to make contact. And the nether regions of those pins are insulated so that if a plug is halfway into a socket and something bridges the pins, it can't make contact.
This is a great design -- for space heaters and ovens and server racks. It's a bit less useful for the low power consumption devices that have come to dominate the market (where maximum draw is well under 1Kw -- often under 0.1Kw).
It does, however, mean that any type of appliance that you might wish to plug in uses the same plug, regardless of what power level it wants - quite a good example of It Just Works, even if the price you pay is huge plugs.
Of course, that does break down a bit when you get to fuses, since you now have to worry about using different capacity fuses for appliances with different expected maximum power draw (3A for most things, 5A for the odd high-power small appliance, 13A for anything involving a heater...)
Actually, UK buildings typically contain at least three different standard sockets and plugs--the big ugly ones (with a supply of four different fuses needed), a mini version of that design commonly used for table lamps and floor lamps, and a third design allowed in bathrooms so you can plug in an electric shaver (electrical sockets and even light switches are ordinarily barred from bathrooms). There are also many different kinds of lightbulbs (screw-in, push-in, push-and-turn-to-lock-two pins) in many different physical sizes (as well as different wattages). Running a family house requires a considerable stock of bulbs and fuses, which explains all the "electrical supplies" shops which are unknown in the US. Up until about 10 years ago, in my personal experience, UK small appliances, lamps, etc. were sold with bare AC wires and the householder was expected to add the needed style of plug; now everything comes with the huge plugs.
What are these mini plugs? Everything I've ever seen has either the BFO plugs or the wee razor type plugs that go into the BFO ones with an adaptor. I've never seen a socket in a house for razor type plugs (although hotels do have them) - I guess new properties might have them.
And the nether regions of those pins are insulated so that if a plug is halfway into a socket and something bridges the pins, it can't make contact.
That's not really true, you can still get electrocuted if you put you finger on both bolts.
And that plug is massive. Luckily you can use any sticklike thing to allow continental plugs to be inserted (which incidentally I'm doing right now -- hello from Edinburgh)
The L+N pins are insulated half way down so you can't touch any metal part that is in contact with the supply.
The supply terminals are also covered by shutters so you can't put anything in them when there is no plug in the wall.
Australian plugs aren't designed to carry any significant physical weight, as far as I could tell (I was in Melbourne a month ago). The thickness of the live and neutral blades is similar to that of American/Japanese plugs, rather than the round pins common in the EU or the rectangular cross-section pins used in the UK. On the other hand? "Nowhere near as horrible" fits the bill for about 95% of purposes -- because nobody should be expecting a 230 volt mains plug and socket to double as a structural support!
Not at all. NZ plugs are the same design as Australian ones and mine seem quite capable of carrying a reasonable amount of weight - I have never ever seen one of our plugs fail under anything resembling sensible use. They're quite capable of carrying, say, a hefty attached transformer.
And since the pins are angled, even a two-pin version is pretty hard to accidentally wiggle free compared to the two round pin European plug (I think some European countries have extra bits as well that might help?). Definitely does not deserve comparison to the awful American plug design.
> There's also a second reason British plugs are robust and fused: they're built to carry up to 3 kilowatts at 230 volts. (None of your wimpish American 110 volt mains juice here! Nothing quite makes your hair stand on end like accidentally touching a live pin carrying 230 volts and 13 amps ...)
Mainland european grounded plugs pretty much all handle 15A/230V, and none looks like a battlecruiser (see the well-known and widely used "CEE 7/7" aka "Type E/F hybrid": http://en.wikipedia.org/wiki/File:CEE_7-7.jpg)
That design has been around for a while now, I very much like it but I believe that they will find it very hard to have it CE marked. I work as a product designer in the UK and have been involved in the design of a device that plugs directly into a wall socket, the regulations on the design of the UK plug are very stringent and this probably doesn't pass. With that said though I think this is a very good design and would love it if the regulations were changed and this was achievable.
Brilliant design, but ganging up unfused plugs like that spells 'fire'.
It's like plugging in a cascade of extension cords.
I don't like the mobile pieces either, they are:
- structurally fragile
- likely to break off and decrease safety
- in the case of the contacts a source of contact resistance
which causes energy to be lost as well as an
increased fire risk
- if they are 'wired' a spot where the wiring will break
because of fatigue issues
Good industrial design takes in to account the function and safety issues as well.
Electrical plugs are a source of some amusement in Europe, in spite of being a 'union' we are not even capable of designing a plug that satisfies everybody and for some this has become symbolic of the dissent in the various states against EU conformity.
Something to point to every time some European starts lecturing about the metric system or A paper sizes. Overcoming existing standards is damn hard, and it’s not just laziness or stupidity which prevents systemic standard changes.
NOt fair! Do you know they are "unfused", "fragile" or dangerous? You made that up!
As for ganging plugs, this approach has an advantage over other (e.g. American" standards - there is the possibility of keying the "ganged" plugs by rating, so for instance only 10-amp plugs could be ganged to the 40-amp main, thus preventing fusing issues.
The American plugs are no contest, they're junk. Just optimized for cost with terrible degradation as they get older, the same goes for the wall socket.
I've seen multiple blackened areas around wall sockets in relatively new houses in the US and Canada due to ridiculously high contact resistance.
The fuse in these plugs - assuming there is one - is in series with the consumer, not in series with the pass-through to the next plug, so yes, by ganging them up you're bypassing the fuses.
That's kind of logical too, otherwise you'd have to be matching the plugs in decreasing order of load (which in itself would not be a bad idea).
Fragile because they have moving parts, anybody that has any experience with electrical stuff knows that as soon as there are moving parts involved in something as basic as a connector that you're looking at an increased failure rate.
Dangerous because they allow the users a degree of freedom that has led to lots of trouble in the past, to the point that 'gangable' designs in plugs have been outlawed in lots of countries.
The fuses in these devices can do whatever the one in the wall does, how can we tell by looking how it works?
As for moving parts, I wonder how that interlock in the wall-plate works. Also, seems like my two-year-old can stick a fork into the ground pin just as easily as any other. And current flows thru the ground, yes, that's why its called a circuit.
Dangerous - yes, if not keyed. That's kind of a cool idea, if its not easily defeatable like the ground on 3-prong cords in the US- they actually sell adapters in every hardware store that simply ignore the ground!
The contacts on one socket protrude in to the next. Which is also the most logical thing to do (otherwise it gets too thick). So no fuses between sockets, just three wires 'down' towards the consumer one of which is fused (the little red tab on the left).
I believe the picture before ( http://www.iconeye.com/images/news_july_09/choi_uk_folding_p... ) is how that looks before the 3 mini-plugs are inserted. The block with 3 cords coming out isn't 3 in "physical series", but a special 3-way adapter that fits the slim (unexpanded) new plug they designed.
( Disclaimer: I'm in the US and I've a three-way adapter with a cut off ground prong for traveling, so feel free to take what I say with a grain of salt )
If we're speaking about US residential wiring, current never flows thru the ground wire unless there's an electrical fault.
There are 3 electrodes -- hot, neutral, and ground. Current flows thru hot to neutral (both slotted openings). The ground is the round pin.
It's true that, back at the panel box, neutral and ground are connected together. But, current should never flow thru the ground wire to get there! That wire is strictly a safety mechanism.
The relevant terms in the US electrical code (the NEC) are "grounded conductor" (neutral) versus "grounding conductor" (ground).
> It's true that, back at the panel box, neutral and ground are connected together.
Only if you have only one panel. If you have multiple panels (aka pony panels) the connection from neutral to ground (aka the 'bonding connection') is made in the panel where power enters the premises.
This is true, but also orthogonal to my point, which is that the grounding connector ("green wire", "round prong", or "ground") is not part of the circuit in US residential wiring.
but ganging up unfused plugs like that spells 'fire'
Nah, it'll be fine. Actually this sort of thinking is probably because of the "dangerous plugs" pictures we are always shown as children. A stuffed up socket just looks automatically dangerous to us.
I guess you're coming from the perspective of overloading the socket. This is surprisingly hard to do - but you can do it equally well across multiple sockets (basically, if your fuse breaker is going to let it burn it doesn't care much where the devices are plugged in :)) so it is something of a misconception to consider a crowded socket particularly dangerous. People happily use an 8 gang extension cable without batting an eyelid.
More importantly having fuses in the plugs is unlikely to help all that much, the crucial fuse is the one in your circuit breaker. The current will divide across the sockets (my circuit theory is rusty so I won't try any figures :)) and it is the socket taking the brunt. While you would likely eventually see a spike that trips one of the plugs I'm betting the socket catching fire is more likely.
And, finally, I suspect these would be rated (well, if they weren't vapour-ware) for devices with internal fusing or low power draws. I'd also suspect that the plug "holder" would be fused.
BTW it is somewhat moot anyway because I believe those red tabs are a fuse holder :)
The big difference between a single 8 gang extension and this system is that you're putting all those connections in series, whereas in an 8 gang extension they're in parallel.
That's a lot of contact resistance, this socket already has twice as much contact resistance as a normal one (because of the twist in the contact section).
If we're talking 'light' consumers, say below a 100W or so you might get away with it but if a 'heavy' consumer would be plugged in as the last element in a series of 'light' ones you'd be concentrating an awful lot of energy in to a small spot.
But hey, what do I know about electricity ;)
At 10 mOhm (new and very clean) per contact with 5 plugs 'ganged' up that's 5x4x10mOhm or .2 Ohm. With a 240V working voltage and a 2 KW consumer that would be 8.3 Amps so about 1.6 V drop, 8.3x1.6=13 Watts, which the copper wiring alone can probably remove without any heat building up.
If the contacts wear and get older they could get to as much as .3 Ohm apiece. Now you're looking at 5x4x.3 Ohm, 6 Ohm, in total so that's a 49 V drop, almost 400 Watts to dissipate just in the contacts. That's a lot of heat.
That's why some older wall sockets will get warm (or even hot) when you plug in a large consumer.
And your circuit protection will not care even a little bit about all this, it's just another heater.
Hmm you sure they are pulling in series? Depends on the design on the plug but I imagine it works the same way as any other multi-socket (pulling it in parallel), why would they set it up to work in series (that would be a big design flaw). One imagines that once this made it to the engineering level (this is just design, right) this would be sorted out.
If we're talking 'light' consumers, say below a 100W or so you might get away with it but if a 'heavy' consumer would be plugged in as the last element in a series of 'light' ones you'd be concentrating an awful lot of energy in to a small spot.
Think about what is likely to have these sorts of plugs; Laptops, for example, usually pull under 2A. Which means you could have 10 plugged in before it starts to be a problem, and even pulling 20A to your socket (which is a common rating for mains sockets) still leaves plenty of leeway.
I'm not sure what my iPhone or radio alarm clock is rated for (am at work atm) but I can't imagine they add up to more than 1A draw.
As I mentioned, the problem on mains networks overloading comes, usually, from a faulty trip switch. If it is doing its job the most that you can do is trip it (and maybe fry some equipment that isn't earthed/fused properly). Stocking up a plug is pretty safe; again, as mentioned, it is easy (and more common) to overload the whole circuit via a number of plugs :)
EDIT: meh, it's impossible, anyway, for it to be set up in series, otherwise you wouldn't be able to pull power correctly.
with 5 plugs 'ganged' up
Uh, there are three plugs in the design?
But this is a reasonable concern (the heat issue). In practice it is not too much of a worry, if a device is demanding 2KW this plug is clearly unsuitable (for a number of reasons).
So the current for the last load passes through all the intermediary sockets. It does not pass through their wiring but it does pass from pin-to-pin. It would have to and no engineering trick will get you around that when you're piggybacking stuff.
> Think about what is likely to have these sorts of plugs; Laptops, for example, usually pull under 2A. Which means you could have 10 plugged in before it starts to be a problem, and even pulling 20A to your socket (which is a common rating for mains sockets) still leaves plenty of leeway.
Until someone plugs their hairdryer or fryer in to the last one, which is possible because it is still valid socket.
Hmm.... yes, I see what you mean. But it comes back to the same issue; which is that if you are overloading it to the degree that it passes the rated value then the trip switch is the failsafe. The socket is at just as much risk.
You wouldn't (in the UK anyway) be able to sell these if they were rated less than the socket.
You would be doing something that seems safe, that will not trip the breaker but that will cause a problem. Just the fact that you can gang a bunch of stuff that is rated does not mean that there aren't any hidden variables here, and contact resistance is exactly that. Very easy to overlook.
That's why 'three way' connectors were outlawed in many countries (but not in all):
That's the UK version, there are others for different places.
The euro-plug variety of them has been outlawed for so long that I can't even find an image of one.
People would get up to all kinds of creative uses for these, such as 'wonder why I can't plug on three-way in to another', and if that works why not several.
They're also known as 'firestarters', any idea why ;)?
I'm still unconvinced.. the way overloading usually causes fires is heating cables till they short and cause sparks/fire. But that is by the by, my main issues:
If all of the mini-sockets are low rated there is no danger, because of how the socket is set up, if you use the other socket for something with a big draw (i.e. if you have a dual socket and plug one of these into it next to something with a big load it will not overload it).
If you overload this device or the socket it will trip the circuit breaker. Same as if you plug all the devices into different sockets on the main.
Heat is unlikely to be an issue, even with contact resistance it is related to the device it is powering - and I contend that this is not a plug you would use, rate, recommend or legally allow for high power devices. If you're powering three laptops it works out to about 1W for the whole device (rember, while the cable goes to each socket the pins are part of the device circuit, the parallel branch, not the main series).
Unless I'm mistaken this community is about innovation. Making his prototype is a long way along the implementation process and beyond from 'pie in the sky' stage.
Any monkey can innovate. Watch while I innovate the following new word: gronkuiotis. What matters is not innovation but well-engineered ideas. That is, ideas which will work in reality rather than in gronkuiotis, I mean, design-world.
Now I happen to think that this project has some merit, though the rotation of the two main plugs will never pass muster -- it'll break quickly and at any rate almost certainly will rapidly become a fire hazard internally after a few turns. But that's probably fixable.
But what I think the GP was getting on about, and what also annoys me greatly as well, is that there are many "designers" (i.e. artists) who think that engineering is the easy part, and what really matters is "innovating". The mindset of "designers" goes like this. "Let me think of this cool version of a chair! Now I just need to find a lowly engineer to do the menial engineering part, I'm sure it's inconsequential." Design-first-engineer-second is how you wind up with poorly engineered "innovations" like these: http://www.strida.com/en/products/
The basic problem is that most artists have no training in making something which actually works. It's not sexy to get something to work. It's sexy to draw pretty pictures.
When I was a little kid I used to draw spaceships where a lightbulb was focused through a long series of lenses until it became stronger and stronger and was blasted out the back, Star Wars Propulsion style. I was quite the innovator, and had some awesome spaceships with impressive lens sequences. That didn't mean my idea contributed to the global discourse.
Yes, this sort of thing is of a piece with architecture students getting internet kudos when they design neat little shelters for the homeless to be made out of recycled cardboard - terribly clever, except that they estimate thousands of USD for each unit and admit that these "homes" won't survive being rained on.
I've read somewhere that automobiles are typically created by the designer first - they draw up the prototype and then maybe make some 3d models of the vehicle. Then, once it's approved they move the project over to the engineering team and they're tasked with figuring out how to fits all the cars parts inside this new design (shocks, motors, drive terrain, etc.).
So for the case of automobiles, the designer is first, engineers second. Obviously the teams will work together to make compromises but it certainly gives merit to the power/value of the designer.
i think you over-engineered your comment and it broke.
your statement is a gross generalization about "designers", biased toward "engineers", and completely ignores two facts; 1) great products are a combination of both, and 2) most products don't achieve greatness for a variety of reasons that may be unrelated to either party.
You're not wrong, but swombat has, like myself, seen this at least four times on HN already. So, we're not interested in it anymore until it's a product.
They should just switch their infrastructure to the "Euro"-plug as soon as they can, like the rest of Europe already uses since ages. Not only is the "Euro"-plug by far the most solid, durable and safest plug, but it will help the Brits and the rest of Europe to be in-sync with eachother on the consumer electronics compatiblity front. Now that the UK has already taken the step to 230V like the rest of Europe, they should complete the rest of the move.
"The continent" is normally - in English - a shortened form of "continental Europe". Are you saying that you moved from somewhere east of the Urals or perhaps Turkey (if you don't believe that that's culturally European, although the part west of the Bosphorus is indeed part of the continent).
And adaptors are pretty pricy for things with no active parts.
So you're suggesting changing every single plug socket in every house/business/office premises in the UK? Then changing every single plug on every appliance you own (or using a converter)
OF course it would happen over time. ITs not any huge issue - certainly not bigger than the issue of selling different appliances every 1000 miles across Europe.
Adapters are 10-cent items in bulk.
In America we have more than one standard we live with every day - two-prong plugs, 3-prong plugs, 220-volt plugs vs 110. You hardly every even think about it, except when you're shuffling through the pantry drawer, looking for an adapter.
Safest? The euro plug is a compromise, so that it will fit in a wide variety of existing sockets, and the standard version isn't even grounded. It's mostly for pretty small devices.
There's IEC 60906-1, but I don't think any country ever adopted that.
It's much easier to unify currencies than to change every existing socket. As most adapters solve most of the problems, and it's easy to manufacture country-specific devices, this isn't really a big deal in my opinion.
The 6-7 versions are all referred to as Europlug for some reason. The CEE7/7 is the grounded "compromise" one. This is the one I implied, which is the most common grounded connector in Europe today.
The German Schuko with the French contact added? Never heard that given the europlug name, but that's probably due to me being German, where the old-fashioned name just stuck and only the CEE7/16 is given the "euro" prefix.
Yeah, I was quite surprised that this is now a de facto standard, as most of my previous European travel took me to locations where another system was used (e.g. Italy, UK, Ireland).
For longer than I can remember, it was very rare to find a European appliance that didn't work in the UK (and vice versa). The only recent developments have been in tighter regulation so that all electrical products produced in the UK must be guaranteed to work in Europe (and vice versa).
I don't think that Europlugs are more solid, durable or safer than British plugs either. Comparitively speaking, they're flimsy, unfused, unearthed and the wall sockets can't be made to close up without a plug inserted.
> They should just switch their infrastructure to the "Euro"-plug as soon as they can, like the rest of Europe already uses since ages.
The only "euro" plug (CEE 7/16) only handles 230V/2.5A, it was made to be compatible with every continental europe wallsocket (and low-power Class II appliances), not to work with big appliances.
The second most compatible european plug is probably the CEE 7/7[0] (Type E/F Hybrid), which combines the german "Schuko" plug and the french Type E, the Type F being widely used across continental europe, and the Type E adding a few more countries to the mix.
Past that, Switzerland, the Danemark and Italy have their own plugs (though according to Wikipedia, the Type E is now allowed in Danemark).
Or perhaps they are less devoted than you to the church of HN. I'm flagging it, but not because I've seen it before (I have) but because of the hyperbolic title and writeup.
My problem with this design is that it doesn't provide coverage for the pins making it less safe. A similar design which included the shield but tilted the pins could retain most of the safety characteristics of the standard design without being vulnerable to (say) kids sticking fingers near partially inserted pins.
I want the italian type L plugs, except it uses flat pins vs. rounded pins (rounded pins always seem to fall out at the slightest force, it's extremely frustrating) and have a plastic covering for part of the live wires like the british plugs do. Outlets would have 4 to 6 plugs standard instead of one or two. The Schuko plugs are huge monstrosities.
the female plugs in the adapter are not to spec to female outlet plugs. so it can't be legally sold there. (me thinks. in Brazil you can't sell outlet stuff that are not up to government spec)
no matter how well it fits or looks. Unless he managed to implement the shutter activated by the earth plug and minimum depths for the live contacts in that little box. Then i would be honestly impressed.
the female plugs in the adapter are not to spec to female
outlet plugs. so it can't be legally sold there. (me thinks.
in Brazil you can't sell outlet stuff that are not up to
government spec)
That's not a problem in the UK. You can sell non-standard-shape plugs and sockets as long as they're up to the safety spec in all other respects. I believe that also means that they have to be sufficiently different from the standard ones that it's impossible to attempt to fit a standard plug into a non-standard socket (or vice versa).
Have you ever held an english plug in your hands? These things are closer to a battle tank than an AC power plug. Forget about flimsy american crap, english plugs can be used as assault weapons.
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[ 3.0 ms ] story [ 176 ms ] threadThe FAQs on his site claims it will be released this year: http://www.madeinmind.co.uk/faq.php - I sure hope so.
The reason plugs in the UK are so big is that each one must be individually fused. And the reason for that is something called a "ring circuit".
In a ring circuit you have, say, a 40 amp fuse at the mains/box. From this you send out two wires, each rated only for 20 amps, going in a circle around the house. You can now supply 40 amps worth of power using only cheaper 20 amp wires. (Since the current can flow over both wires at once.)
But this means that the wires going to an individual appliance are far too small for the main breaker, so each appliance gets a fuse in the plug.
Ring circuits have serious drawbacks, but they helped during a time when there was a copper shortage.
And ever since then the UK has been stuck with huge plugs.
They tend to rest on the plug's back, and hurt a lot when you step on them.
> Any other countries use them?
India and South Africa use the so-called Type D plug[0] (also called Type M in its 15A incarnation), which is similar but uses round plugs (type D is actually an older english standard). Some other south-east asian countries also use Type D. The english plug is called "Type G" and used in a number of former colonies and protectorates[1], especially in Africa and the Middle East.
[0] http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Type...
[1] http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Type...
I wish someone would come up with a design which doesn't hurt so much when you accidentally tread on one.
http://www.minkyu.co.uk/Site/Product/Entries/2009/4/20_Foldi...
The promo shots of the final working model don't show how you get at the fuse, but I'd be very surprised if it has been overlooked. I suspect it's something to do with the red dots.
Indeed, the red dot is the plug cover. This set of blogspam pictures don't show it, but previous sets (the folding plug first made rounds in mid-2009) showed how the plug works. You can see an "action shot" simulation of the plug in the video: http://www.youtube.com/watch?v=f6DvjKkGT6s#t=1m46
Given a choice between US plugs (spark, fall out of sockets, flimsy, dangerous, bendy pins), and UK plugs (Built to last, don't spark, fused, solid) I know which I'd choose.
There's also large advantages to having each plug individually fused - individual appliances blow rather than the whole circuit.
So I wouldn't say we're "stuck with huge plugs". The only real time it's a slight issue/pain is when you go on a plane and the cables take up a bit of space.
"The only time its a slight issue"???
How about manufacturing, shipping, selling, storing, repairing, and paying for that overdesigned eyesore? How about looking at it? How about moving the couch out from the wall so the dang thing will fit back there?
Also, when you decide to put a lamp somewhere, you typically make sure the cable is not somewhere that can be tripped up.
But as I say, all rooms in the UK come with a fitted ceiling light, and a light switch by the door. So lamps are less common.
Ok, the alarm clock. or the hair dryer (into the bathtub! Yay!) or the wireless access point...
Hairdryers are usually used in bedrooms.
The last time I tripped over a cable was..... years ago. I can't even remember doing it. It's not an issue we have.
Yes, they do. (The UK, or even Europe, is not the whole world.)
> Hairdryers are usually used in bedrooms.
Hairdryers are used in bathrooms if there's a plug in the bathroom.
Sockets do not exist in bathrooms in the UK.
It is usually, but does not have to be, an overhead light.
An alternative that is also code-conforming is to have the switch control a socket (typically, the bottom plug in several duplex receptacles in the room) where a lamp is plugged in. Sometimes people don't actually plug a lamp in there, so the switch does nothing, and maybe that's what you've been irritated by.
If the wiring is done this way -- e.g., bedrooms and living rooms -- it can be quite flexible if you want to rearrange the room layout. You move the furniture and plug the lamp into the bottom receptacle where-ever it is convenient and sensible.
Cars kill 100 times more people than electrocution (not to mention severe injuries, which are rare for electrocutions), so they're probably a more important risk to worry about. Any slight difference in car accidents is going to swamp electrical concerns.
The latest source that I could find said that 400 people died of electrocution in 200, down from 670 in 1990.
I wasn't able to find any information on the UK. However, being from the US, I'd probably bet your wiring over there is safer.
http://www.cpsc.gov/library/electro.pdf
I prefer the UK plug too. But you missed one other very important point of pain: the pain of standing on one. As the flex on a UK plug leaves from the bottom, it has the unique property of tending to lay down on the floor with pins facing upwards.
That would be the point. Better to damage a plug slightly than get the plug through your feet.
16A at 240V in a grounded plug that is very easy to protect against tiny fingers and that you'd have to be trying real hard to get your fingers on when inserting it, even in pitch dark.
Forwards compatible socket with the Euro plug. (that's the thin, ungrounded one with just two pins, one live, one neutral).
It will do anything from your phone charger to a light duty welder.
It's not really that it's forwards-compatible, but that the europlug was created specifically for this purpose. It's compatible with all european sockets but the english one I believe.
http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Type...
Edit: I'd just be happy if Europe picked a single standard and stuck with it. It's ridiculous to have to carry all sorts of converters for what are, in the grand scheme of things, not very long trips.
There is a mechanical/electrical machining process called spark erosion aka electrical discharge machining. Every time you have a spark a tiny bit of the metal of both contacts evaporates. Of course that's when you want it to happen, in sockets with plugged in loads you really don't want it to happen.
Over time this process accelerates and it has been the cause of many house fires in the US.
The fact that such sockets are placed in walls made of mostly wood placed right next to an upright stud does not help either.
Sometimes they're so bad you can actually smell the ozone.
And sparks are not the cause of many house fires, you just made that up. The sparks are harmless, and I've never seen a plug with erosion on it. Just because you can do it doesn't mean it actually happens.
American plugs spark (much) more frequently and strongly than their equivalent UK/EU plugs because the spring pressure from the side contacts is insufficient to maintain good contact over the lifetime of an installation, especially if the plugs are also worn. The fact that typically the current is twice as high doesn't help either (though if you get zapped it's less of a problem than in 230V installations, the US uses a balanced 110 system for most residential circuits where only a few receptacles which are of a different design have both sides of the step-down transformer outside of the house running to them).
The UK/EU plugs are of a much more solid construction than the American ones, as are the wallsockets they go in to.
I've seen US sockets that made an audible buzz while operating and get extremely hot (hot enough to melt the plastic). Not good.
The usual way in which it gets to this state is that a socket has been overloaded a couple of times, or heavy load is plugged in or removed while switched on, the contacts have corroded or have some soot build up on them and then the resistance increases enough to start a runaway process that ends with the socket failing altogether or with the socket getting so hot that the plastic outside cover will start to melt.
At that point all bets are off, especially in houses that are mostly constructed from wooden sticks instead of brick or concrete.
Another cause of trouble like this is that there was a short period when due to the supply issues with copper electrical wire made of aluminum was tried in residential installations in the US.
These required special fixtures so the wire would not come lose as the aluminum compressed over time thus shrinking away from the contact and causing an airgap and thus sparking.
This kind of wiring is no longer 'code' and if you have such wiring it wouldn't harm to periodically tighten up on the screws to ensure good contact.
Aluminum oxide build-up compounds this problem.
People always blame 'short circuits' for electrical fires, but most of the time this is nonsense, since the breaker will almost always instantly trip in a short circuit situation. That's what they're designed to do.
Half shorts (shorts that are of a resistance low enough to cause significant heat build-up and high enough not to cause the breaker to trip) and faulty contacts (intermittent contacts, sparks and thus heat) are a much more frequent cause of fire.
Another big cause of fire is counterfeit junk hitting the market and do-it-yourself types that don't know the difference using this to wire up that extra socket for a space-heater in the attic.
You have soot on your contacts???? Corrosion? Did it rain inside your house?
NEVER tighten aluminium contacts! You will cause exactly those problems that you describe. If there is a problem with it you need to remove it, apply the anti-oxidant paste and reinstall.
But aluminium to the contacts is very rare in america these days, where it does exists it's usually been pigtailed with copper.
Rural areas, farmhouses, but one building I lived in in Toronto had a problem (a bad one) with one of the sockets and it was a fairly recent upgrade from what I remember.
> You have soot on your contacts???? Corrosion? Did it rain inside your house?
No, simply an installation from the 70's still operating in 2005. There are millions like that. And I don't live there anymore, I'm back Europe now.
> NEVER tighten aluminium contacts!
Not over-tighten, tighten. You should do it to the proper torque (there are special tools for that).
> But aluminium to the contacts is very rare in america these days, where it does exists it's usually been pigtailed with copper.
Yes, that's the slightly newer method, also since outlawed (and used as a way to fix problems).
The biggest problem I think with the alu wiring was not even that it could not work, but that people would use it with the wrong connectors, the al specific sockets were pretty pricey.
The only place where I know that aluminum is still used in residential wiring is on the entrance wire from the pole to the transformer, usually that's a very tricky connector that uses wedges to make the contact.
If I found myself in a house with aluminum wiring I'd probably rewire the whole thing just for safety. Costly (especially with the US system which staples cables to studs) but worth the peace of mind.
The correct installation uses anti-oxidant to seal it, then you tighten it enough to crack the aluminum oxide, and the anti-oxidant protects it. If you tighten it without fresh anti-oxidant you are creating a hazard.
And pig tails are not outlawed - quite the opposite, they are the recommended way to handle aluminium wiring.
Ah ok, I see what you mean now, yes that makes good sense.
As for the pigtails, as far as I know you can not make any new wiring with Aluminum in residential installations, pigtailed or not (I left my code book in Canada because it is of no use to me here, maybe there is some up-to-date online resource). Industrial use is still ok I believe.
Yes. But if you already have aluminium wiring you can - and should - add pigtails to it to make it safer.
In my two months in the USA, I observed more arcs and electrical crackling noises than I have in the rest of my life in AU.
Just my anecdotal 2c.
But I could be all wrong, as I'm no expert beyond having a drawer full of adapter plugs.
Or did you mean that you only need to run one set of wire instead of multiple ones to multiple outlets?
I'm not sure why. Is the skin effect sufficient to explain this?
That uses way less cabling than any other network.
To that end, the live and neutral contacts in a British socket are shuttered. The long earth pin on the plug makes contact before the live or neutral pins are in the socket, and once in contact, raises a shutter to permit live and neutral to make contact. And the nether regions of those pins are insulated so that if a plug is halfway into a socket and something bridges the pins, it can't make contact.
This is a great design -- for space heaters and ovens and server racks. It's a bit less useful for the low power consumption devices that have come to dominate the market (where maximum draw is well under 1Kw -- often under 0.1Kw).
Of course, that does break down a bit when you get to fuses, since you now have to worry about using different capacity fuses for appliances with different expected maximum power draw (3A for most things, 5A for the odd high-power small appliance, 13A for anything involving a heater...)
I've only ever lived in houses with the big uglies.
All lightbulb headaches have been due to IKEA and their foreign ways.
That's not really true, you can still get electrocuted if you put you finger on both bolts.
And that plug is massive. Luckily you can use any sticklike thing to allow continental plugs to be inserted (which incidentally I'm doing right now -- hello from Edinburgh)
And since the pins are angled, even a two-pin version is pretty hard to accidentally wiggle free compared to the two round pin European plug (I think some European countries have extra bits as well that might help?). Definitely does not deserve comparison to the awful American plug design.
Mainland european grounded plugs pretty much all handle 15A/230V, and none looks like a battlecruiser (see the well-known and widely used "CEE 7/7" aka "Type E/F hybrid": http://en.wikipedia.org/wiki/File:CEE_7-7.jpg)
http://news.ycombinator.com/item?id=927714
http://news.ycombinator.com/item?id=782236
It's like plugging in a cascade of extension cords.
I don't like the mobile pieces either, they are:
Good industrial design takes in to account the function and safety issues as well.Electrical plugs are a source of some amusement in Europe, in spite of being a 'union' we are not even capable of designing a plug that satisfies everybody and for some this has become symbolic of the dissent in the various states against EU conformity.
Have a look here how crazy the situation is:
http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets
If we can't even design a common AC plug that everybody will actually adopt that's food for thought.
[1] http://en.wikipedia.org/wiki/Euro_zone#Members
[2] http://en.wikipedia.org/wiki/Schengen_Area#EU_member_states_...
As for ganging plugs, this approach has an advantage over other (e.g. American" standards - there is the possibility of keying the "ganged" plugs by rating, so for instance only 10-amp plugs could be ganged to the 40-amp main, thus preventing fusing issues.
I've seen multiple blackened areas around wall sockets in relatively new houses in the US and Canada due to ridiculously high contact resistance.
The fuse in these plugs - assuming there is one - is in series with the consumer, not in series with the pass-through to the next plug, so yes, by ganging them up you're bypassing the fuses.
That's kind of logical too, otherwise you'd have to be matching the plugs in decreasing order of load (which in itself would not be a bad idea).
Fragile because they have moving parts, anybody that has any experience with electrical stuff knows that as soon as there are moving parts involved in something as basic as a connector that you're looking at an increased failure rate.
Dangerous because they allow the users a degree of freedom that has led to lots of trouble in the past, to the point that 'gangable' designs in plugs have been outlawed in lots of countries.
The fuses in these devices can do whatever the one in the wall does, how can we tell by looking how it works?
As for moving parts, I wonder how that interlock in the wall-plate works. Also, seems like my two-year-old can stick a fork into the ground pin just as easily as any other. And current flows thru the ground, yes, that's why its called a circuit.
Dangerous - yes, if not keyed. That's kind of a cool idea, if its not easily defeatable like the ground on 3-prong cords in the US- they actually sell adapters in every hardware store that simply ignore the ground!
Based on this image:
http://www.iconeye.com/images/news_july_09/choi_uk_folding_p...
The contacts on one socket protrude in to the next. Which is also the most logical thing to do (otherwise it gets too thick). So no fuses between sockets, just three wires 'down' towards the consumer one of which is fused (the little red tab on the left).
( Disclaimer: I'm in the US and I've a three-way adapter with a cut off ground prong for traveling, so feel free to take what I say with a grain of salt )
There are 3 electrodes -- hot, neutral, and ground. Current flows thru hot to neutral (both slotted openings). The ground is the round pin.
It's true that, back at the panel box, neutral and ground are connected together. But, current should never flow thru the ground wire to get there! That wire is strictly a safety mechanism.
The relevant terms in the US electrical code (the NEC) are "grounded conductor" (neutral) versus "grounding conductor" (ground).
Only if you have only one panel. If you have multiple panels (aka pony panels) the connection from neutral to ground (aka the 'bonding connection') is made in the panel where power enters the premises.
Nah, it'll be fine. Actually this sort of thinking is probably because of the "dangerous plugs" pictures we are always shown as children. A stuffed up socket just looks automatically dangerous to us.
I guess you're coming from the perspective of overloading the socket. This is surprisingly hard to do - but you can do it equally well across multiple sockets (basically, if your fuse breaker is going to let it burn it doesn't care much where the devices are plugged in :)) so it is something of a misconception to consider a crowded socket particularly dangerous. People happily use an 8 gang extension cable without batting an eyelid.
More importantly having fuses in the plugs is unlikely to help all that much, the crucial fuse is the one in your circuit breaker. The current will divide across the sockets (my circuit theory is rusty so I won't try any figures :)) and it is the socket taking the brunt. While you would likely eventually see a spike that trips one of the plugs I'm betting the socket catching fire is more likely.
And, finally, I suspect these would be rated (well, if they weren't vapour-ware) for devices with internal fusing or low power draws. I'd also suspect that the plug "holder" would be fused.
BTW it is somewhat moot anyway because I believe those red tabs are a fuse holder :)
That's a lot of contact resistance, this socket already has twice as much contact resistance as a normal one (because of the twist in the contact section).
If we're talking 'light' consumers, say below a 100W or so you might get away with it but if a 'heavy' consumer would be plugged in as the last element in a series of 'light' ones you'd be concentrating an awful lot of energy in to a small spot.
But hey, what do I know about electricity ;)
At 10 mOhm (new and very clean) per contact with 5 plugs 'ganged' up that's 5x4x10mOhm or .2 Ohm. With a 240V working voltage and a 2 KW consumer that would be 8.3 Amps so about 1.6 V drop, 8.3x1.6=13 Watts, which the copper wiring alone can probably remove without any heat building up.
If the contacts wear and get older they could get to as much as .3 Ohm apiece. Now you're looking at 5x4x.3 Ohm, 6 Ohm, in total so that's a 49 V drop, almost 400 Watts to dissipate just in the contacts. That's a lot of heat.
That's why some older wall sockets will get warm (or even hot) when you plug in a large consumer.
And your circuit protection will not care even a little bit about all this, it's just another heater.
If we're talking 'light' consumers, say below a 100W or so you might get away with it but if a 'heavy' consumer would be plugged in as the last element in a series of 'light' ones you'd be concentrating an awful lot of energy in to a small spot.
Think about what is likely to have these sorts of plugs; Laptops, for example, usually pull under 2A. Which means you could have 10 plugged in before it starts to be a problem, and even pulling 20A to your socket (which is a common rating for mains sockets) still leaves plenty of leeway.
I'm not sure what my iPhone or radio alarm clock is rated for (am at work atm) but I can't imagine they add up to more than 1A draw.
As I mentioned, the problem on mains networks overloading comes, usually, from a faulty trip switch. If it is doing its job the most that you can do is trip it (and maybe fry some equipment that isn't earthed/fused properly). Stocking up a plug is pretty safe; again, as mentioned, it is easy (and more common) to overload the whole circuit via a number of plugs :)
EDIT: meh, it's impossible, anyway, for it to be set up in series, otherwise you wouldn't be able to pull power correctly.
with 5 plugs 'ganged' up Uh, there are three plugs in the design?
But this is a reasonable concern (the heat issue). In practice it is not too much of a worry, if a device is demanding 2KW this plug is clearly unsuitable (for a number of reasons).
The contacts are in series:
So the current for the last load passes through all the intermediary sockets. It does not pass through their wiring but it does pass from pin-to-pin. It would have to and no engineering trick will get you around that when you're piggybacking stuff.> Think about what is likely to have these sorts of plugs; Laptops, for example, usually pull under 2A. Which means you could have 10 plugged in before it starts to be a problem, and even pulling 20A to your socket (which is a common rating for mains sockets) still leaves plenty of leeway.
Until someone plugs their hairdryer or fryer in to the last one, which is possible because it is still valid socket.
You wouldn't (in the UK anyway) be able to sell these if they were rated less than the socket.
You would be doing something that seems safe, that will not trip the breaker but that will cause a problem. Just the fact that you can gang a bunch of stuff that is rated does not mean that there aren't any hidden variables here, and contact resistance is exactly that. Very easy to overlook.
That's why 'three way' connectors were outlawed in many countries (but not in all):
http://www.rapidonline.com/1/1/8248-3-way-mains-adaptor.html
That's the UK version, there are others for different places.
The euro-plug variety of them has been outlawed for so long that I can't even find an image of one.
People would get up to all kinds of creative uses for these, such as 'wonder why I can't plug on three-way in to another', and if that works why not several.
They're also known as 'firestarters', any idea why ;)?
If all of the mini-sockets are low rated there is no danger, because of how the socket is set up, if you use the other socket for something with a big draw (i.e. if you have a dual socket and plug one of these into it next to something with a big load it will not overload it).
If you overload this device or the socket it will trip the circuit breaker. Same as if you plug all the devices into different sockets on the main.
Heat is unlikely to be an issue, even with contact resistance it is related to the device it is powering - and I contend that this is not a plug you would use, rate, recommend or legally allow for high power devices. If you're powering three laptops it works out to about 1W for the whole device (rember, while the cable goes to each socket the pins are part of the device circuit, the parallel branch, not the main series).
Wake me up when it actually gets implemented and becomes available for real.
Now I happen to think that this project has some merit, though the rotation of the two main plugs will never pass muster -- it'll break quickly and at any rate almost certainly will rapidly become a fire hazard internally after a few turns. But that's probably fixable.
But what I think the GP was getting on about, and what also annoys me greatly as well, is that there are many "designers" (i.e. artists) who think that engineering is the easy part, and what really matters is "innovating". The mindset of "designers" goes like this. "Let me think of this cool version of a chair! Now I just need to find a lowly engineer to do the menial engineering part, I'm sure it's inconsequential." Design-first-engineer-second is how you wind up with poorly engineered "innovations" like these: http://www.strida.com/en/products/
The basic problem is that most artists have no training in making something which actually works. It's not sexy to get something to work. It's sexy to draw pretty pictures.
When I was a little kid I used to draw spaceships where a lightbulb was focused through a long series of lenses until it became stronger and stronger and was blasted out the back, Star Wars Propulsion style. I was quite the innovator, and had some awesome spaceships with impressive lens sequences. That didn't mean my idea contributed to the global discourse.
Of course if you have used "e-gronkuiotis cloud 2.0" we would have funded your innovation with a squilliuon $
So for the case of automobiles, the designer is first, engineers second. Obviously the teams will work together to make compromises but it certainly gives merit to the power/value of the designer.
your statement is a gross generalization about "designers", biased toward "engineers", and completely ignores two facts; 1) great products are a combination of both, and 2) most products don't achieve greatness for a variety of reasons that may be unrelated to either party.
"The continent" is normally - in English - a shortened form of "continental Europe". Are you saying that you moved from somewhere east of the Urals or perhaps Turkey (if you don't believe that that's culturally European, although the part west of the Bosphorus is indeed part of the continent).
And adaptors are pretty pricy for things with no active parts.
Seems like a huge undertaking to me.
In America we have more than one standard we live with every day - two-prong plugs, 3-prong plugs, 220-volt plugs vs 110. You hardly every even think about it, except when you're shuffling through the pantry drawer, looking for an adapter.
There's IEC 60906-1, but I don't think any country ever adopted that.
It's much easier to unify currencies than to change every existing socket. As most adapters solve most of the problems, and it's easy to manufacture country-specific devices, this isn't really a big deal in my opinion.
Yeah, I was quite surprised that this is now a de facto standard, as most of my previous European travel took me to locations where another system was used (e.g. Italy, UK, Ireland).
I don't think that Europlugs are more solid, durable or safer than British plugs either. Comparitively speaking, they're flimsy, unfused, unearthed and the wall sockets can't be made to close up without a plug inserted.
The only "euro" plug (CEE 7/16) only handles 230V/2.5A, it was made to be compatible with every continental europe wallsocket (and low-power Class II appliances), not to work with big appliances.
The second most compatible european plug is probably the CEE 7/7[0] (Type E/F Hybrid), which combines the german "Schuko" plug and the french Type E, the Type F being widely used across continental europe, and the Type E adding a few more countries to the mix.
Past that, Switzerland, the Danemark and Italy have their own plugs (though according to Wikipedia, the Type E is now allowed in Danemark).
[0] http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Type...
It was posted on Reddit a few years ago. It's been posted on HN twice already, it's gone around twitter.
Are you all new to the internet?
http://www.brightyellowcow.com/blog/A-thin-13A-Plug.html
http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Type...
+ http://news.ycombinator.com/item?id=841068
+ http://news.ycombinator.com/item?id=927714 <- This one has some comments worth reading.
the female plugs in the adapter are not to spec to female outlet plugs. so it can't be legally sold there. (me thinks. in Brazil you can't sell outlet stuff that are not up to government spec)
no matter how well it fits or looks. Unless he managed to implement the shutter activated by the earth plug and minimum depths for the live contacts in that little box. Then i would be honestly impressed.