When we recently covered the topic of high voltage safety with respect to mains powered equipment, we attracted a huge number of your comments but left out a key piece of the puzzle. We take our mains plugs and sockets for granted as part of the everyday background of our lives, but have we ever considered them in detail? Their various features, and their astonishing and sometimes baffling diversity across the world.
When you announce that you are going to talk in detail about global mains connectors, it is difficult not to have an air of Sheldon Cooper’s Fun With Flags about you. But jokes and the lack of a co-starring Mayim Bialik aside, there is a tale to be told about their history and diversity, and there are also lessons to be taken on board about their safety.
In the earliest days of domestic electricity, by far its most common use was in lighting. Just as they are today, lighting circuits were hard-wired to receptacles designed for incandescent bulbs. When the first portable domestic appliances appeared they thus only had access to power through lighting sockets, and some of the earliest mains plugs simply replicated the base of an incandescent bulb. As appliances proliferated a variety of plug and socket standards were created to satisfy the need for both electrical safety and convenient access to a mains supply.
Throughout the twentieth century these early sockets were refined, improved, and in some cases superseded by new designs. National standards for voltage and AC frequency were adopted and standardised by the electrical safety bodies of individual countries, and further safety refinements such as earth contacts, partially insulated pins, or shuttered socket receptacles were incorporated into updated versions of each standard. If you are a global traveller or you are selling mains-powered equipment internationally you’d probably be tempted to describe the resulting proliferation as something of a mess.
That’s the Great Thing About Standards…
![A CEE 7 plug designed to be compatible with the earthing arrangements of both French and German variants. Chamaeleon [PD], via Wikimedia Commons.](https://hackaday.com/wp-content/uploads/2016/05/cee_7-7.jpg)
A Plug in Full: The BS1363
Bewilderment at the variety of sockets aside, it’s worth looking at the features of a modern mains plug and socket, examining their purpose, and taking a look at their wiring. An article on how to wire a plug might seem a little basic for Hackaday, but since it’s the first line of defence in mains appliance safety it’s vital that you ensure every piece of equipment that crosses your bench has a properly wired connection so it’s an important area to study. Ask any grey-haired electrician for their horror story tales of badly wired plugs they will have encountered over their career, and maybe then you’ll understand.
So we’ll now consider a mains plug in detail. Because this is being written in the UK we’ll illustrate it with a British 13A 240V BS1363 plug and socket, but the safety features are the point here rather than the individual standard. The BS1363 has all the features you would expect of a modern high-voltage mains connector, so consider them equivalent when shown here to the corresponding features on your local plugs. As an aside, is it a matter of national pride that people consider their own national standards to be better than those of their neighbours? For Brits that feeling probably ends abruptly when they first step on an upturned BS1363 in bare feet. Let’s just say if the pins on your plugs don’t protrude at 90 degrees to the flex, your feet are very lucky.
The BS1363 socket has three rectangular receptacles for pins. At the top is the earth, below left the neutral, and below right the live. There is always a shutter covering the live and neutral pins, opened by the insertion of the earth pin. This is a safety feature missing from earlier British sockets, which were open to whatever could be inserted by a curious but foolhardy child.
The plug has the corresponding three rectangular pins, with the earth pin significantly longer than the other two. Our second safety feature, this ensures both that the earth connection is the first to be made and last to be broken, and that the shutter is opened only as the live and neutral pins are entering their receptacles.
The live and neutral pins are partially insulated, with only the section towards their tips exposed. This is another safety feature that ensures that you can’t accidentally contact live pins when unplugging. The earliest BS1363 plugs lacked this insulation.
Removing the cover of the plug, on the right is the BS1363’s feature that makes it unique among the rest of the world’s mains plugs; it contains a replaceable fuse in the live conductor. This is a safety feature not to protect the user from shock or the appliance from damage, but to protect the cable from fire in the event of a short circuit. The value of the fuse should thus be chosen to match the current rating of the cable, though sadly the majority of BS1363s seem to contain a 13A fuse whatever the cable.
At the bottom of a BS1363 plug is a cord grip, usually a plastic clip, or a band with two screws. This safety feature secures the cord and takes the strain to ensure that the conductors can not easily be pulled out.
The final safety feature of a properly-installed plug comes through the work of the person who attaches it to a cable. If you imagine that the cord grip fails and the wires can be pulled from their terminals, you might understand that the first conductor to be disconnected would need to be the live, followed by the neutral, and finally the earth. Thus the installer should carefully cut the conductors to length to ensure that the live wire – brown in UK appliances – is shortest, followed by the blue neutral wire and finally by the green and yellow earth wire which should be the longest. Your plug should come with instructions with the appropriate lengths for each wire.
In a world moving towards moulded cables and plug-top power supplies it’s true to say that familiarity with the internals of your mains connectors is a less universal skill than it might once have been. But while the Average Joe might have to wire a plug a little less often than they used to it’s likely that you as a Hackaday reader will still find yourself with a mains lead or two to fix. It’s thus been worth taking a little time to consider the humble mains plug, and we hope you’ll go away and look afresh at your own connectors. We know you’ll all have your own favourites and bugbears from the worldwide selection of plugs and sockets, so make your case in the comments.
[Banner image source: United States Patent 7070460]
I would mention that it would be unusual to have a uk wall socket that isn’t switched, so you don’t typically have plugs scattered on the floor to stand on.
https://youtu.be/UEfP1OKKz_Q
Except when you are sorting through a box of random mains leads to find the last “figure-eight” style end! and end up with about a dozen plugs and leads lying around on the floor when the doorbell rings!
Tom’s explanation is perfect, wish other countries would adopt a similar style system it’s very safe and basically idiot proof.
I’d say he didn’t think his video through very well or he’s simply blinded by his patriotism…
For the rest of the EU (Gemany, France + middle EU) plug it’s impossible to have the plug “halfway” and touch the conductors while they are still live, because the socket is recessed, making this physically impossible (without mechanical damage to them), thus no need for insulation kludges…
The safety version of the plug relies on both neutral and line being pushed in at the same time, it’s impossible to open it with just one…In the old days when safety plugs did not exist, there were “child protectors”, a cheap plastic insert that you (or the kids) could not remove without a key-like device, again because of the recessed socket. You can’t do this with the brit one.
The so appraised fuse in the plug – other countries discovered individually fused circuits and size them accordingly to the sockets and intended use, instead of having house sockets that can power an industrial sized welder :P
There’s also one more benefit to the EU system – if the appliance is crapily made (rather common for cheap shit), the breakers will most likely save you, because the house wiring has to be certified, the power company will not connect a house to the grid without it. If you have a Brittish plug where the chinese factory cost cut the fuse out and replaced it with a piece of wire – you will burn.
Case and point – the EU plug is just as, possibly even more safe while being smaller and more practical.
The only system that is even more inherently safe is the EU 5-prong 400V plug, because it’s designed for industrial use. One downside is the size (and cost).
More problems you missed: He was able to plug it just the ground to bypass the shutters and, if he bypassed the shutters like he shows, he could have plugged it in backwards as well.
I think having something like ( – | ) where the parentheses are ground and – hot and the | neutral would be safer.
Coaxial arrangement would probably be better, as that would allow the plug to be rotated at will ;-)
You should really check will first. He may find it very psychologically distressing to have plug rotated at him.
That is because the extension he was demonstrating with is not designed to the correct standard. It is not possible to do that on a proper one.
You can get lockable child covers for the UK sockets too, my sister was a childminder and has to have them fitted all round her house.
I prefer shunko’s myself too, but this isnt a reason to bash the uk system.
If your very very bad, you can defeat the earth shutter mechanism with a screwdriver, then if you force it, a continental two pin plug will go in and function in a uk socket. Its probably illegal, but I may have done it more than once or twice in a jam when travelling…
It’s called SchuKo, an abbreviation of Schutz (= protection) and Kontakt (= contact).
It refers to the eathing contacts at the side.
It is a myth to believe that child minders require socket covers in Britain, but unfortunately some inspectors are ignorant of the dangers of using them and tell carers that they should be used, which is completely against Ofsted policy, see http://www.fatallyflawed.org.uk/html/faq.html#Q2
I remember seeing contractors in Iraq open the shutter with a pocket knife, and sticking in the raw wires from an EU extension cord with the plug cut off…
Why exactly does the UK even have government agents allowed to force people to have specific safety equipment.
Oh wait, it looks like these are requirements for child care centres and that makes more sense.
You can’t just plug a welder into a standard socket in the rest of the EU? :(
You can.. as long as it’s current draw is below the rating of the socket (or better the circuit your connecting it to).
You won’t be able to connect a 24Vdc/200AMP aluminium welder to a normal SchuKo socket though and make it work at the higher settings. ;-)
I’m not sure why you think the insulation on the contacts is more of a kludge than recessing the whole socket.
In the UK we have to have circuit breakers for individual circuits as well as fuses in our plugs. So we won’t burn because of cost cutting Chinese factories.
Re: ” the rest of the EU (Germany, France + middle EU) plug “, that is not one plug! You are ignoring the fact the multiple Italian, and quite different multiple Danish plugs are different again. There are still many non-recessed (also unearthed) sockets in use across Europe, especially in France and The Netherlands, which accept the French and German style plugs and provide no protection against touching live pins of partially inserted plugs.
German sockets are still not required to have shutters, although they are available. The shutter opening method which requires simultaneous insertion of both live pins (neutral and line) was originally developed by MK in Britain in the mid 1950s and has been in use in MK sockets since then. Modern high quality sockets from MK, and some from Hager and Legrand, now require the simultaneous insertion of all three pins of the plug to open the shutters.
Modern British houses also use central circuit breakers (they previously used central fuses for each circuit) and RCDs to limit the duration of shocks. The continental system of circuit breakers rated at 16A for each circuit cannot possibly provide adequate protection for the cables connected to the most commonly used plug, the 2.5A rated Europlug, which is usually fitted to a 3A rated flexible cord, but sometimes to a tinsel cord rated at 0.1A. Having an appropriately rated fuse in the plug is vastly superior to the Europlug nonsense!
I would guess that many UK Monster plugs are fitted with 13A fuses, well in excess of their loads, since most come with a 13A fuse installed. Some safety!
The majority of UK plugs come permanently fitted to the appliance with which they are used. These plugs are actually rated according to the flexible cord to which they are attached, and are fitted with fuses appropriate to that cable, as required by the standard. If you do not understand this, please refrain from making up nonsense.
In the United States the 2008 NEC requires tamper resistant receptacles with the same “shutters” over the live and neutral wires that are described in these British outlets.
…and of course they cost about triple what the non-tamper-resistant outlets cost.
I don’t think I’ve ever seen one of those installed. I guess adoption of 2008 NEC is moving slowly.
They’re fairly common from what I’ve seen, but look every similar to the old ones. Perhaps you’ve seen one without realizing it?
Here’s a link with a picture of an inexpensive tamper resistant outlet from Lowes (a popular supplier of construction material) http://www.lowes.com/pd_294955-1571-3232TRWCP8_1z0rv1iZ1z0yt2jZ1z0zy8f__?productId=3236646&pl=1
I have tangled with one or two of those. You almost need a hammer to insert the plug for the first time!
There will always be proof of that there are idiots in the world :P
If you’ve ever lived any length of time in the UK, you know thats not true, sooner or later everyone does the hop of pain while shouting foul language.
Me and my wife were talking to our kids about this with friends around because they were curious about a uk mains plug on a console someone gave them, and someone pointed out the pain of having 3 squared off pins in the soft arch of your bare foot to them and every person there who lived in the UK at some point winced at the memories. I swear I still have the brand of the territory – 3 holes in the arches of both my feet.
I’ll probably regret saying this, but I’ve lived in the UK for most of my life and don’t recall ever having stepped on a plug… I’m quite curious why people would leave them lying around like that. Makes me think of Sideshow Bob stepping on rakes:
https://www.youtube.com/watch?v=2WZLJpMOxS4
Of course that’s not true. Normally the reason to unplug a cable is not the lack of a switch but the lack of a free socket for another device. So the switch on the socket does nothing to prevent cables lying around.
I’m not that convinced that have fuses at the plug saves much copper. The conductors will have to be sized to carry the total current safely. Even if the smallest load only draw less than half an ampere.
The fuse in the plug has NOTHING to do with saving copper! It is there to ensure that the flexible cord attached to the plug has appropriate protection. Central fuses and/or circuit breakers are rated to provide appropriate protection for the building wiring, whether they be the 30A fuse or 32A circuit breaker used in a British ring circuit, the 20A circuit breaker used in a British radial circuit, or the 16A circuit breaker used in a typical mainland European radial circuit. None of these provides appropriate protection for lower rated flexible cords which, for 230V smaller appliances, are typically rated at 6A, but many cords (especially those connected to 2.5A Europlugs) are typically rated at 3A, and even as low as 0.1A! The idea that a 16A central breaker can protect such cords is clearly nonsense, which is why the British plug fuse is such a superior solution. If Britain had decided to use fuse-less plugs when the ring circuit was introduced, then it would be necessary to provide a local fuse, which would most likely be a 13A fuse situated in the socket (historically France used socket fuses, so there was a good historical precedent if needed). However, as the fused plug was introduced at the same time as the ring circuit, such a requirement was completely unnecessary.
You took his troll bait! Quick, spit out the hook!
https://hackaday.com/2016/05/19/hackadays-fun-with-international-mains-plugs-and-sockets/#comment-3025019
Watch out, they got me too!
; )
The British Monster plug, also found in Malaysia, Singapore (and some countries where they have construction projects) along with HongKong, are totally over-engineered. They are designed in such a way that the quantity of brass drives the cost, these days, through the roof. The lone prongs must be good for a hundred amps or more. And, yes, devotees, I am very familiar with the Ring Main concept.
Of course, these Monster Plugs are typical British – incompatible with anyone else – as with their membership in the EU.
The US/North American/Japanese 2/3 pin variant is a little dubious since they appear to be designed to run warm/hot under rated loads.
The Continental 2+ Ground seems to be a common sense medium between the extremes of the UK and US with grounding and polarity options available.
TYPO
The LINE prongs must be good for a hundred amps or more.
Have you actually bothered to check the comparative costs of Schuko cord sets and BS 1363 cord sets? I know that rewirable Schukos cost more than rewirable British plugs (based on DIY store prices).
Did you know that 50 countries use the British plug?
And, does it not bother you that your “common sense medium” is a very outdated design, is not smaller than a typical British moulded plug, and is severely compromised on safety features?
I am glad you mentioned ‘outdated’ since the Monster’s birth was around 1941 and was followed by “British Standard 1363:1947 Fused-Plugs and Shuttered Socket-Outlets” which makes the Monster around 70 years of age.
Your “50 countries” have not standardised on them, they are to be ‘found’ in many countries. For example, here in VietNam, where Singapore investors have built hotels and condominiums, these outlets are often found. The standard, these days, in new Vietnamese construction are two or three prong plugs with combination sockets for either Euro round or North American flat prongs. I have these in my two hotels and are manufactured by Panasonic. They will carry a sustained load of 10 Amperes with minimal temperature rise.
They are also polarised and shuttered. There is NO compromise on safety.
Given the price of raw materials these days, every opportunity must be taken to reduce manufacturing costs without compromising safety. The Monster plug hardly dies this when you compare the prices to be found on the InterNet.
In my forty plus years of travelling as a technician I have determined the best connector of all are a couple of wires with bared ends and a small screwdriver to fiddle the shutters.
BS 1363 is the 1947 response to a report published in July 1944 1947, NOT 1941! Lie #1!
The BS 1363 is the most MODERN socket in general use, and the ONLY post-war plug in widespread use. (Schuko is 20 years older, the US plug was is 40 years older).
Your example, Vietnam, is NOT one of the 50 countries listed by the IEC which use the BS 1363 standard. LIE #2!
Above you have written “the US/North American/Japanese 2/3 pin variant is a little dubious since they appear to be designed to run warm/hot under rated loads.” Now you say: “they will carry a sustained load of 10 Amperes with minimal temperature rise”, which is, of course, only 2/3 of the rated current for a US plug. Not only that, but Vietnam is one of those countries which is stupid enough to use a plug designed to operate at no more than 125V at a supply voltage of 220V, a terrible example! For the truth on the dangers of multi-standard sockets see http://www.universalsocket.org.uk
You have appropriately shown up your true ignorance with your statement: “I have determined the best connector of all are a couple of wires with bared ends and a small screwdriver to fiddle the shutters”. It tells us all we need to know about your wisdom!
@ Ruth Jones
Rather rash to call someone a liar.
A short history: The late :Lord Reith was chair of a committee struck in 1941. A sub-committee, chaired by Dame Caroline Haslett, President of the Women’s Engineering Society, Electrical Installations Committee, produced a report in 1944. This committee’s report resulted in BS 1363.
AS/NZS 3112, for Australia, New Zealand, Fiji, Tonga, Solomon Islands, and Papua New Guinea, dates from 1990.
The current NEMA 5 standard, predominantly North America, dates from 2005. There are millions more 2/3-blade NEMA connectors than the Monster BS connector.
With reference to VietNam, I never claimed it was an adoptee of the Monster connector – it is imported by developers from Malaysia and Singapore.
Note that I differentiated between the NA NEMA connectors and the Panasonic variant – the latter is a far superior design with full blade/pin/prong contacts along the length of them. They are rated for 240VAC use. It’s on the specifications. NEMA connectors are also rated for 240VAC since even houses have 117-0-117 VAC supplies and frequently the same double outlet will have one socket connected a phase which is opposite to the phase feeding the other for a potential difference of 234 VAC. Wire insulation is greater with an operation temperature of 90C.
125VAC (nominal) is safer than 230 VAC – which why the lower voltage is sites on UK construction sites.
As for my two bare wires and a screwdriver, please note it was MY observation with respect to MY use. I am a certified technician and have an Ontario, Canada, electricians licence (in good standing) and I am a quality control person for my employers who export equipment worldwide.
Have a good one.
Not at all rash when someone is telling lies.
The design of the original BS 1363 was finalised in July 1947:
BS 1363:1947 “Fused-Plugs and Shuttered Socket-Outlets”
What happened in 1941 was nothing to do with the plug, it was the realisation that the whole subject of post-war rebuilding should be the subject of detailed preparation, and so a series of studies were called for by Lord Reith, the relevant government minister (he did NOT chair any of the committees himself, government does not work that way).. The electrical installations committee was convened in June 1942, it was chaired by James Beard, not Caroline Haslett (although she was a member). The Committee published its report which called for a new design of plug in July 1944, that report made no recommendations on the pin style or layout, but does require that the new design be child safe and incorporate a fuse rated at up to 13A. There is no way that any intelligent person could interpret the committee report as an actual design!
The current versions of the standard are just four years old:
BS 1363-1:1995 +A4:2012 “13 A plugs socket-outlets adaptors and connection units – Part 1: Specification for rewirable and non-rewirable 13 A fused plugs”
and
BS 1363-2:1995 +A4:2012 “1 3A plugs socket-outlets adaptors and connection units – Part 2: Specification for 13 A switched and unswitched socket-outlets”
Contrary to your false claim, the current AS/NZS standard is:
AS/NZS 3112:2011 “Approval and test specification—Plugs and socket-outlets”.
The original Australian version was adopted in 1938 as standard C112, but it was not a new design, rather it was an adaption of an American design filed in 1915 under US Patent 1,179,728.
Again, contrary to your false claim, the current American National Standard is:
ANSI/NEMA WD 6-2016 (February 2016) (NOT “NEMA 5”!
What is often referred to as Type B (a designation with no official standing) is actually the 5-15 classification of ANSI/NEMA WD 6. It is a variation of the original Hubble parallel blade two-pin plug which was patented under US 1,064,833 in 1913.
With regard to Vietnam, what you said was “Your “50 countries” have not standardised on them, they are to be ‘found’ in many countries. For example, here in VietNam”.
That is a lie because I was referring to the 50 countries which the IEC list as using the BS 1363 standard, or local variations of it, and does not include Vietnam! If you want to include countries where BS 1363 is “found” then of course the number is much higher than 50, but choosing to deliberately misinterpret someone’s statement is a clear case of dishonesty.
Another lie is your new claim that NEMA connectors are rated at 240V, in fact ANSI/NEMA WD 6 includes connectors rated at various voltages up to 600V, but 5-15 is most definitely rated at 125V 15A, no higher.
Do you not understand that it is vital that a mains connector should NEVER be rated at a lower current than the plug which it is intended to receive? Any connector designed to receive a 15A rated plug MUST be rated at a minimum of 15A! (A 10A socket intended for a 15A plug completely contravenes IEC 60884-1 “Plugs and socket-outlets for household and similar purposes – Part 1: General requirements” which is the internationally agreed standard on mains plugs and sockets to which all national standards adhere? No responsible company would make a 10A socket intended for a 15A plug!
Everything you have written demonstrates that you are the last person who should ever pontificate on electrical safety.
I’d rather that my plug was over-engineered than on fire.
It should be noted that the lampholder plug was also popular for ripping off the electric company. In several places light and power were charged separately, and at different rates, lighting being the lower. These plugs let the user tap in to the lower cost supply. It didn’t take long for the power companies to wise up, and dual rate disappeared.
In Poland in many apartments cellars have no wall plugs, so using special lampholder extender/plug that has plug on one end, lampholder on the other and two standard plugs on the sides, was usual way to power tools in cellars. Especially when cellar lights have one meter, and the bill is divided between all residents of the building.
Note that the US plug has none of the safety features mentioned in the article!
Another drawback of the US plug is that unlike the UK plug, you can’t beat someone senseless with it.
But you can use a power strip as a baton and bludgeon someone with it.
What it does have, though, is an absurdly low cost to produce. Not to mention legacy support! Who needs safety standards or common sense when you have those things, right?
It’s nice to know that we Americans still have ???????????????? guts left. Europeans are a bunch of babies.
I get the “accidentally grab too much” shock on the 2 prong US plugs at least once a year. Then I yank them out by the cord for a few months until I get tired of fixing them, then I do it normal for 6 months until I get shocked again. It’s a vicious cycle.
I would say you’re in the minority. This has not happened to me ever.
Ah, the classic “doesn’t happen to me” “argument”.
I think the ‘classic “doesn’t happen to me” “argument”’ applies quite nicely here. Removing a plug from a socket is not a freaking stochastic process. If you are unable to remove plugs from a socket without getting shocked *multiple times per year*, I would say you are suffering from mental challenges that do not present in someone that is a bit more centrally located on the scale of human intelligence.
The reason argument was quoted was because it’s a classic fallacy, ie non argument. Your “argument” (ie lack thereof) is ignorance.
Oh, and that last part, where you’re trying to build up an “argument” by abusing slander and negative personal characteristics? That’s even worse than not having an argument at all.
Hey, take your petty argument to someone else’s thread!
I would add that this only happens when the plug is being blocked by something large close by and the wire being bent is preventing the plug from coming out easily. Thus an atypical grip (index and middle finger) on the plug and higher force needed for extraction. Also the comment was a fair bit of a hyperbole in response to the humerous comment it was a reply to.
Luckily it’s only 120V :p
“It’s a vicious cycle.” But cheaper than caffeine for waking you up.
It’s not exactly true, because with half the voltage, Americans get electric shocks for wimps :)
Hey! My fuse is bigger than ???????????????? puny eurofuse!
But the main thing is, we Europeans have free health care(most countries).. So if we get electrocuted, we dont have to pay the health care costs
but my taxes are lower, since ours isnt entirely free.
If you get electrocuted, you do not need any more healthcare. Although funerals are not cheap, too.
Of course it’s different if you get shocked, injured, etc.
I disagree. 1st, a grounded US plug has a longer ground pin just like the one in the article allowing it to connect first and disconnect last. 2nd, the tamper-resistant plugs have entered the US electrical code in the last decade and can be seen in new construction (probably similar situation in the UK). 3rd, the fuse is unnecessary since any short would trip the 15 amp breaker.
The fuse is a good idea. That’s why most Christmas lights have them. 15A through my red and green LED’s on tree setup would equal fire.
How would 15A get through the LED string?
I was saying that’s why there is a fuse. Most have a female plug on one end. Kratz seemed to think that the house breaker was good enough. I was typing too fast I think.
The wires could short together just out of the plug. Like Jenny said in the article, the fuse protects the cable, more than anything, prevents fire. You’d probably use a 3A fuse on xmas lights, though you can get 1A but they’re not common. The fuses are the same shape as the ones you use in electronics, except they’re filled with sand, or some other stuff, to absorb a bit of the explosion and vapourised metal when the fuse blows.
The fuse makes a HELL of a bang, actually, when something like a 13A kettle goes wrong. An actual explosion, with black marks all round the socket. Socket still works of course, we build ’em tough.
When I was a kid I installed a fuse into a light socket. It went off like a flashbulb when I turned on the lamp (It made a cool “light ring” effect, which now I’m sure it was just retina cells dying).
Christmas lights typically are fused becase the wire is usually thin and cant handle the as much current as the outlet could supply. The choice is between the fuse or 15A wiring.
But the whole wiring system is protected, from what I understand, at a lot lower current rating than uk stuff, and some cords do have fuses in them in spite of that – look at Christmas light strings. Also, now we have tamper resistant recepacles, our outlets are generally a lot smaller for general receptacles, so reaching in and hitting the hot prong is pretty tough. And we now have arc fault protection required on most branch circuits in the home.
Not necessary because of the low voltage. :-) You have to have very bad luck to get a lethal current through your heart with 110V.
North American electrical systems, also used extensively in half of Japan, these days offer polarised pins AND safety shutters.
“these days “, which started with the 2008 NEC, is correct, but that still leaves the vast majority of installed sockets without shutters, compared to every single BS 1363 ever made having shutters. Can you see the difference?
The Japanese version has historically had no earth, the requirement for earthing in houses having been introduced only in 2005.
Remember how delightfully compact some US appliance plugs used to be?
http://imgur.com/EiugnQv
You can still buy two-prong replacement plugs. You just have to file down the wider neutral to make them as simple as possible.
But, of course, don’t forget to connect the green and white wires together inside that modified plug.
Jeez… You try to tweak the safety kiddies and they don’t take the bait…
Don’t take it personally Rod, some trolls are fun to feed, but you may not be one of them.
I was going to bite, but saw the hook and swam away!
The trolls are still full from last week.
No, no, no… you need to give the green wire a proper earth-ground:
http://i.imgur.com/rbAo0Vc.jpg
Your image link didn’t work, no doubt because this site blocks pix of things stuck into a bunghole.
Further proof that human intelligence *is* evolving in some strange ways.
I do remember those. And I remember the household radio had a terrible 60cps hum. I ‘fixed’ it by reversing the plug to get the receiver in phase with the transmitter. Parents thought I was a genius.
“…reversing the plug to get the receiver in phase with the transmitter.” You forgot the /joke tag.
Haha. Grandma cords.
Got hit by one of those as a child. Bare feet on concrete floor. The outlet wouldn’t let the plug come out without rocking, yanking, fussing and saying words small boys shouldn’t know. I knew not to yank on the cord, for safety sake. With the plug half way out, my very small index finger slipped between the plastic tablet and the wall. I was surprised to have survived that. Dad then replaced all the outlets in the house with ones that worked more properly.
When Brazil switched officially to NBR 14136 plugs ( https://en.wikipedia.org/wiki/IEC_60906-1#Brazilian_NBR_14136_standard ), almost every Brazilian was really mad with the “new” plug, mostly because lot’s of products here had the NEMA plugs or Europlugs.
I find it to be a nice plug, actually. It’s compact, so the power strips and AC adapters are small. The sockets are deep, so even without partly insulated live and neutral pins, you can’t touch them while plugging or unplugging. They are still compatible with the Europlugs.
I just wish they kept the IEC 60906-1 standard.
They could have avoided most of the complains if they had left out the half insulated part. That makes using the bad new pins in older ( or slightly worn out ) receptacles hard to contact. Then people start using cheap 0.99 chinese adaptors, to connect things. Also, break away the ground pin because said adapters and wall receptacles do not have option for said pin.
If they were really worried about safety ( and not the company producing the new pins and receptacles belonging to relatives of government people ) they could have just designed a recessed receptacle able to use the standard American plug .
Just had a look at your link. I had no idea Brazil has two mains voltages, and both available on the one plug! Incredible!
Usually you have just one voltage where you live. Some cities use 127V (usually older cities), some use 220V and in some rare cases, both are available, though not on the same home/building.
We also use three-phase AC and connect some high current appliances (heaters) hardwired through a disjunctor to two phases to get 220V where mains voltage is 127V.
Yeah, that sucks. At least most stuff is 100~240V now and we don’t have to care too much unless it has a motor or something like that.
Since I live in europe, where we have the schuko standard, I prefer that.
On double insulated equipment we use the small two prong plug without earth (like the Brazil one), and it fits the big grounded sockets too.
On powerstrips it is not uncommon to have a few of each to save space, of course any kind of wallwart will obscure the neighbouring outlets.
But what I never liked is the US standard, firs the issue of using 110V, then the flimsy prongs and the outlet that doesnt contact unless you bend the prongs on the plug slightly.
And the wireing standard in the US is terrible, only to be outdone by third world countries.
I think I took more pictures of sloppy electrical work in the US then anything else.
But they will probably get their sh*t together, shortly after going metric and learning to write dates in the correct order :P
(But hey, I love the US for many other reasons, it’s just like a retarded cousin from the countryside, just cant´t hate them)
I’m not aware of any country where people write dates in the correct order. Dates should be YYYY MM DD. I don’t care about choice of separator characters (so long as they are consistent) but the most significant digits should be on the left, just like numbers!
This is the ONLY sensible way to write a date. Why? Because this is 2016 and everything is computerized now. Most significant digits on the left means it sorts correctly!!!!!!
For computers we have the unix time stamp. Includes date and time and fixes all the time zone and DLST bull. But yeah, YYYYMMDD is better then the MMDDYYYY. But I like the [D]D[M]MYYYY because most of the time the day is the most important part of a date. :p
The cool thing of YYYYMMDD is that, when placed in front of a file, it will automatically order these files.
If you start with the day/month it will order on that first, and then the year, which is weird.
2016-05-03 is correct. https://en.wikipedia.org/wiki/ISO_8601
I mostly use the [D]D[M]MYYYY format, but have no problem with YYYYMMDD. But the mixed up US format always confuses me it’s just not “right”, not logic.
In Hungary the proper format is YYYY. MM. DD. This is one of the very few things that are logical in our horribly complicated rules of spelling and grammar. Of course the EU had to force writing best before dates in DD/MM/YYYY …
I totally agree with you. However it is amazing how many people have not figured this out for themselves.
DD MM [YY]YY is just as logical, the way the British do. Then again we say “19th of May” rather than “May the 19th”. But at least our way is in some sort of order, even if it’s the reverse of the arithmetically sortable way.
we dont use “the” unless we leave the month out. example today is the 19th, or today is may 19th.
speaking of logics.. for computers and automatic filenames, the YYMMDD is the most logical. Then if you have a measurement spanning over multiple days, the file are always in the right day order.
Haha. I lost track!
We were talking about electrical outlet standards! But somehow UNIX and expiration date formatting snuck in.
This was great.
January 1st, 2016. It’s a perfectly logical order. There are 12 months. 365 or 366 days. Infinite years. Smallest amount to largest amount.
Small to large?
That is quite a BS argument.
Like writing everyones name in alphabetical order?
Days are 24 hours.
Months are ~30*24 hours.
Years are ~365*30*24 hours.
Small to large hea.
YYYYMMDD is readable for both American people and humans.
Since you will get your month before the days, and we get the logic (small to large).
The problem with MMDDYYYY and DDMMYYYY is that you can’t differentiate 02-03-2016, it could be either 2 March or 3 February
Oh well. I guess you settled that problem.
.
MMDDYYYY
there is nothing to stop someone writing YYYYDDMM though is there, and no way to tell.
Just write DD MMM YYYY instead, in any order you want. problem solved. no it doesn’t require extra storage its simply a formatting issue, the same as sorting by date shouldn’t be affected by the regional display
Japan I think? My region uses DDMMYYYY but I got used to scripting stuff into YYYYMMDD_SomeBackup.7z long time ago and it kind of works for me – even when I move crap around and timestamps get lost/replaced, sorting by name still helps out.
Actually in the 21st century Europe is more like America’s children. Our military shields them from the Russian and Chinese militaries. Our generous allowance enables them to play with nice things like trains, cute smaller versions of our cars and talk in their own languages. Oh and Pee-Wee’s playhouse sized electrical plugs.
America and wars yes, they’ve started far more of them than they can finish, and yet they claim they “shield” the rest of the world from more harm?! Reflection has never been your strong side.
We finished a couple of your wars.
true that.
Better late than never I suppose…
but I think the rest of the allies would have defeated the Nazis without the USA’s military
We don’t really care about the rest of the world. Unless they get in our way.
we are a young country, we still cant compete with the amount of wars european countries have started before we even existed.
The metric system is a Jacobin plot!
The shocko standard?
Replaces the old “Zappo” and the “Kill-U-Quik”.
US wiring standards are decent, it’s the implementation and enforcement that’s the problem.
As mentioned in the Tom Scott video linked above, and surprising for those of us who never lived in Britain, is that for a long time, appliances were sold without a plug and it was an essential skill to be able to wire one. This is apparently changing, but for those of you confused about it, that’s why.
When we made colour displays, the ones that went to the UK market had to have an extra couple of feet of line cord, so our power plugs could be cut off and new, functionally identical ones could be fitted to the cable by local unionised labor.
I always found that strange. Here in continental Europe I am supposed to not “touch” (work on) any electrical connection, also for repairchange of a plug I am supposed to consult a licensed electrican. Which – of course – I all the time (*) did. Ha-Ha!
And in UK people are officially allowed to do this work by themselves. Are the British considered smarter by the authorities?
(*) never
Yep! British person here, and I can confirm that we can wire plugs.
I think insurance companies don’t like you doing it, but they really don’t like you messing with electric stuff that’s permanently attached, like the sockets and light switches.
You’re allowed to put in spurs and extend rings.
Yep! We’re allowed to rewire plugs!
The fuses in British plugs aren’t just any old fuse either – they’re sand-filled ceramic ones rated to break something like 6000A of fault current. I’m not sure quite why our plugs need such robust fuses and would probably rather not find out.
because if the switch is on before you plug it in, the fuse will pop WHILE YOUR HOLDING THE PLUG.
fuses dont always go “pop”, they sometimes go BANG, this would cause a minor hand injury, or if your face is reeeally close…
the sand absorbs part of the blast to the point where death, or even injury is so unlikely, its almost considered impossible.
also i believe the fuse is supposed to be considered safe even with the plug cover open (or taped lightly), this avoids lawsuits if the screw-threads are worn.
PS: i do not live in the country with this plug, so i am only guessing, based on watching videos of hollow glass fuses (and lightbulbs) blowing on youtube, that is can be very dangerous for someone down on the floor with face VERY close to outlet.
While there may be some truth to your claim that a sand-filled fuse is less likely to explode than a glass one, I believe the main reason for their use is their improved ability to break a fault (for a given size).
From wikipedia:
Miniature fuses may have an interrupting rating only 10 times their rated current. Some fuses are designated High Rupture Capacity (HRC) and are usually filled with sand or a similar material.
The “improved ability to break a fault” due to the sand is precisely why they do not explode!
Oh, the misinformation here… The sand in fuses is not to increase the break current (what would be the point of having the fuse if you’re just trying to keep it from blowing?), but rather to cool and quickly extinguish the arc if the fuse fails.
Quote: “…extinguish the arc if the fuse fails”
Hmm … note sure if failure mode is fail or not fail. By your choice of words, the fuses failure mode would be not failing so then I ask – what would it’s “not failing mode” be?
+10 for anyone who understands.
Only 2 points for understanding? (I think in binary, as you have surely observed by now, but am converting to decimal for clarity.)
As long as you’re going to be pedantic, my friend, you might at ???????????????????? use apostrophes correctly [it’s “not failing mode”].
i was more or less referring to the ceramic VS glass body.
yes sand helps cool the arc, by doing this it prevents explosion, the fuse is supposed to contain the arc by staying in one piece.
in my last post i should have included links:
basics and less-severe scientific style testing (low-voltage, only glass fracture)
https://www.youtube.com/watch?v=6JACvzfmIzE
counterfit fuse inside said plug (slowmo plug burns and flys)
https://www.youtube.com/watch?v=KVJVswLbqaA
Yep apparently the Chinese have been producing fake, unsafe fuses. Because the world didn’t think they were a bunch of conniving dicks before.
Once you’ve heard they even make fake eggs and – I kid you not – fake jellyfish (that unlucky people then proceed to eat…), hardly anything can ever surprise you in that department ever again…
The break current (more correctly “breaking capacity”) refers to the over current that can be extinguished as the fuse blows, not the current that the fuse blows at. At some current all fuses will carry on passing current because a spark develops across the fuse, part of the fuse specification defines the maximum current that can flow that will still be extinguished.
When designing things for use on the network in the UK this will be minimum of 250,000 amps.
I think you might be confusing two different ratings – the rated current, and the breaking capacity. Sand absolutely does increase the breaking capacity and is usually used for this reason. As you say, it draws a ton of energy out of the arc, thus extinguishing it.
Because until the main breaker trips or a cable melts the entire current available from the local substation (transformer) can be delivered to your outlet. If you have a short circuit in the flex going to your appliance (or in the appliance) there will be a few nanoseconds where hundreds of amps, possibly even thousands are being delivered through the short. This is why the fuse blows and the sand is there to arrest the arc to stop an explosion.
If your short circuit just caused 25A of current for example it may take a couple of minuets for your fuse to blow.
It is worth remembering that wherever you are in the world the final protection for your house is the FUSE fitted by the electricity supplier at the point where the supply enters your premises. (to which you do not have access). Central breakers can fail (indeed there are some Chinese fakes with no working components inside!), and a failed breaker does not break, but a fuse will always melt at some level of current, even if it is a little higher than intended. Fuses are the simplest most reliable protection available and still have an important role to play in the overall scheme of overcurrent protection. (This is in no way to disparage the important role of circuit breakers, or RCDs.)
The feeds to houses in Kampuchea, Laos and VietNam enter the meter box and terminate on fast-action (no tolerance) appropriately rated circuit breakers.
The breaker and the meter are in a sealed partition in the meter box.
These breakers are accessible by the consumer, through an opening, and often serve as the main house breaker – even when the breaker boxes have duplicative functions.
Fuses necessitate a service call from the supply authority and waste labour and money.
Ring circuits made with wire 1/2 the size it should be, with a power hungry appliance nearer one end of the loop. Power imbalance overloads the longer part of the loop.
Are ring circuits still allowed for new construction in the UK? They were never allowed in the USA, all circuits must be a direct run to a single outlet or can have multiple outlets along the parallel conductors.
If individual wires are used they must be in metal or plastic conduit. Flexible plastic insulated wire with two or more conductors may be run alone or inside conduit. The reason is for safety in case of failure. Should the wire get overloaded to where it melts the insulation, the wires will touch and make a dead short, tripping the breaker or blowing the fuse.
Wayyyy back when there was ‘knob and tube’ wiring. Tubular ceramic insulators with one end having an enlarged knob were inserted through holes drilled in studs, rafters and joists. Individual wires were threaded through the insulators, often several inches apart. The problem there is an overheating wire could not touch another wire to cause a short. So there could be long runs of glowing hot wire causing fires. A few years ago the church my parents were married in caught fire from that. It was being converted into a house. As a Christmas gift to their family, the occupants had finished the kitchen and had connected a couple of heaters to dry the paint or something. Middle of the night a fireman on his way home pounds on the door to wake them because flames were pouring from the roof. The person they’d bought the church from had claimed he’d completely redone all the wiring… So a week before Christmas they were out a house. They’d decided to go to Disneyland that year instead of buying each other gifts. The tickets for the trip were the only thing they were able to save. That was one crazy cold night. The fire department poured on so much water the street down the whole block had 2 or more inches of ice on it.
So if you’re renovating an old home, check for knob and tube wiring and if it has any, replace it.
Yep, ring mains are still the thing in the UK.
In domestic UK installations the ring main still predominates as the most efficient solution, but there will normally be several of them (eg, living area, kitchen and sleeping area) and often several radial circuits also. Designers are expected to evaluate the individual needs of any installation and choose the appropriate topology, or combination of topologies, which best fits the need. 70 years of practical experience of the Ring Final Circuit in the UK has proved its value and safety.
No, the cable in the ring circuit is NOT “1/2 the size it should be”, it is the appropriate size for the chosen topology.
one of the things that people in the US don’t realize is the US power system feeds 2-phase 120vac 60hz to houses. this is how we have multi-voltage systems here (ie 240 for heaters/stoves/dryers and 120 for lighting and other stuff)
A split-phase, or single-phase three-wire system not a two phase supply. It is single phase because both voltage waveforms are in phase, or in step, with each other only the voltage is split to the center tap of the supply transformer.
what i mean by two phase power is it’s two phase as in the two phases are 180 degrees from each other, not the outdated two phase that is 90 degrees from each other.
http://lib.store.yahoo.net/lib/yhst-14463325294384/Electric-Household-2Phase
If they were 180 deg out of phase with each other they would not sum to 240V , which they do. See further:
https://en.wikipedia.org/wiki/Split-phase_electric_power
Indeed. When I rebuilt my house I ran 12/3, carrying both “phases” plus the single neutral, to many of my outlets (with the hots split) so that I could draw 20A from each outlet–very useful in the kitchen with lots of high-current appliances. If the phase angles weren’t as they are, the neutral could carry more than 20A with both hots loaded. As it is, worst case (unbalanced hots) is 20A, best case (balanced loads) is zero. My electrical inspector was confused, but finally got it.
@Rodney-
Do you have the circuits gfci protected via a 2-pole breaker? Or did you rebuild you house in the 70s… All kitchen counter receptacles should be gfci protected if you are following code, as in early 70s and onwards,
2014 nec code requirements with all the ground fault and arc fault protection required in homes, including kitchens multi-wire branch circuits have become a horrendous wiring method, especially when trying to remodel a home bringing it up to present code requirements….
Also- ALWAYS remember what happens in your neutral wire fails. Your plugged in devices will receive a nice shot of 240V which will burn out surge arrestors in the best case, and burn out electronics in the worst case…
To be fair in the very early days of electricity being used in industry, in the US, there was in fact a two phase system. It was in place mainly for induction motors. The funny thing about two phase is that it requires four conductors while the vastly more efficient three phase system only needs three conductors, eventually leading to the standardization of three phase power.
Yes, there are true two-phase systems around, but this is not what is being delivered to homes. The old Niagara Falls 40Hz station produced two-phase AC.
I didn’t know about the 40Hz system, but I have another one for you…in the northeast, Amtrack ran a 11KV system at 25Hz for traction motors.
I was in error, the Niagara Power station contained twelve vertical axle, 25 Hertz generators rated at 8320 kVA each for a total generating capacity of 100 MVA. I don’t know why I thought it was 40Hz
In Sweden you had to pay a fee for the number of sockets you had installed, Therefore these adapters with sockets that you could fit in a light socket (E27) were very popular: http://home.swipnet.se/elsamling/stickproppar_skarvuttag_1.htm
There’s also some old plugs at the top of the page.
Honestly as a European that emigrated to the US when I was a kid. I can say this about US plugs, they are dead nuts reliable, simple and backwards compatible. The voltages in the 110v range are hair raising but not too bad either. The older I get the more I dislike europlugs every time I go to Italy. I have yet to see one wall receptacle that is not worn out over there. Allot of heat cracking and lots of nasty little plugs that are too large for their own good. In contrast I have replaced 40-50 year old wall receptacles in my own home. All of them were functional, all of them were not worn out to the point a plug had to be wiggled to get contact. At least in Italy the plugs are a true frustration for me. Its the only country where there are like 3 different standards, 2 prong fat/2 prong skinny, and 3 prong straight……. Nasty stuff. I will stick to a US plug thank you. Its also way sleeker to look at.
I used to hate the British plug because to me it looked like a silly sign of arrogance, national pride and lack of common sense (like driving on the left and using miles, stones and other silly measurement units). However, having thought a bit about it, I realise it is actually one of the best plugs anywhere. It has a nice big surface of contact, it has a fuse by default.. these features alone are enough to make it the best standard.
People really don’t understand the point of the fuse.
1. All sockets are supplied using a ring-main supplied at the distribution point with a 32A breaker or fuse. Therefore any single socket is capable of delivering at least 32A before the circuit cuts. In order to avoid having to use a flex from the plug to the appliance that can withstand 32A a fuse is installed in the plug.
2. Fuses come in a range of sizes, the most common being 3A, 5A & 13A but other sizes down to 1A are also available. This allows smaller lighter flex to be used on low power appliances.
3. People seem to be under the impression that fuses only protect against short circuits. A fuse also protects against overload situations. If you have for example a TV that has water spilled into it so that a fault condition causes 15A to be drawn that would probably cause overheating and potential fire a fuse will break. It is far better to have your 300W device connected with a 3A fuse than it is relying on a 15A fuse at the board in the case of a US/EU style radial wiring or simply the 32A on the UK style ring main.
So a socket can supply 220V at 32A? ????????????????…… I take back everything I’ve said about Europeans being wimps.
That means that each socket is wired with 10AWG (or whatever the Euro equivalent is) or heavier cable. Sounds expensive!
Not so in the UK – the sockets in a house are normally* wired into a ring using 2.5mm2 cable (Google says somewhere between 12 & 14AWG) which is rated at 24A.
ie:
fuse box –> socket —> socket —> socket —> back to same connection in fuse box
Each ring in the fuse box is fused at 32A, but you have two paths back to the fuse box which splits the load. Obviously this means that on each ring you can only have a maximum of 32A for all sockets in use.
From what I’ve seen, the majority of houses split the rings as one ring for the upstairs and one for the downstairs. My fathers house is somewhat odd in that one ring seems to be the front of the house and one the rear (I would have been too young to understand the potential swearing that might have happened while he was discovering that oddity…)
*you are (or were) allowed to take a spur off of the ring to a socket that accepts a single plug. Spurs off of spurs are a no no for obvious fire-in-wall inducing reasons :) There may also be other exceptions – I’m trained as an EE, not a sparky….
A ring circuit is an absolutely insane system, with too many ways that something can go horribly wrong. It may save some copper, but as a wise man once said: penny wise, pound foolish. The radial system is simple and flexible and, if like me, you occasionally need to add circuits to accommodate some high-power tools (I’m now at ten subpanels in my large DIY house/workshop :-), you don’t have to worry that you’re going to screw up the circuit loading and fry your wiring.
hehe 10 subpanels! Respect :)
Haha. But most of them look like this…
http://www.4mistersparky.com/images/outdated-panel.jpg
If you inspect and test your installation/modification as you are supposed to then there isn’t a problem. How many fires were caused by ring final circuits that were installed and tested by a competent person? this year? ever? none probably.
Saying that there is certainly a preference for radial circuits especially for high loads. It used to be typical to see just a ring final per floor, newer installs will usually have a radial for the kitchen, possibly a separate circuit for washer/dryer. Topology in the rest of the house is decided based on layout and usage, its not just flung in.
Since the popularity of MCBs replacing fuses and the requirement for RCDs in regs its not unusual to have circuits split or altered when a consumer unit replaces a fuse box.
To say you have 10 subpanels is utterly meaningless. Heavy equipment that requires hardwiring is often put on its own breaker. If you require this many ‘subpanels’ for portable equipment then I suggest you have too many hands or at least look at getting your line voltage increased to something sensible.
Ah, but that’s why we have ring mains in the UK, to allow us to get away with thinner wire (a bit of post-war economising to save copper, I believe).
You left out the bit how Aussies can who buy US electronics can usually twist the pins to fit our local sockets :)
Haha! Thats great.
Ohh, we are all playing with fire.
https://upload.wikimedia.org/wikipedia/commons/7/7a/Australian_dual_switched_power_point.jpg
…Please work this time, image upload.
Well,no – i live in Czech Republic (Europe) and in our country it is this way:
Standard distribution network up to each building is always (if there is exception, they are rare) 3 phase 380V – After this the installation varies – if the house has multiple flats, sometimes they are wired with 3 phases, sometimes simgle phase – all flats which was fitted with larger electrical cooker has 3 phases, countryside is mostly all 3 phase at the house junction box. In the box with meter, there is main breaker – for single phase installation maximum rating is 25A, for three phase you can go over 80A (new house installations are done with 4×16 mm2 Al or 4×10 mm2 Cu at the entry to the house from the street) – the catch is that you pay for the rating of your main breaker – the higher current its is, the more money you pay each month as constant payment.
After the meter you have your flat / house breaker box – there you will have lover rating breakers, commonly 16A for sockets (must be wired with 2.5mm wire) and 10A or less for lights (can be wired with thinner, like 1.5mm wire). If you have 3 phase meter and 3 phase installation up into the flat, its mostly split (except if you use induction cooker, that thing uses 2 phases) into single phases in the flat breaker box. At the countryside, many people operate motors built for three phases and various “equipment” withe different levels of “safety” (380V is the best voltage for your home built welder you know?)
Current Czech standards does not directly proscribe cross-section of wires that must be used for given current rating. There are requirements on temperature rise and fault loop impedance, which then boils down to guideline derating tables based on cable type, cable installation method and cable length. In essence, result from this is that (with copper wiring) for many house-hold installations 1.5mm^2 is perfectly permissible for 16A. (notice how most hobby markets stock large amounts of CYKY(Lo)-3×1.5 and comparatively almost no 2.5)
HAHA…
As a toddler I used to like to put car keys in the hot socket and watch as people grabbed for them. Now I am a reader here…LOL…
GFCI is now standard in any new construction in the USA if it falls within so many feet of a hazard. NEMA and other codes dictate that any dishwasher not only have GFCI but also AFCI as well as the main failure mode of dishwashers is AFCI.
AFCI hasn’t caught up to the breaker panel yet. It adds on average 800 dollars to the cost of a new house in the US. However, just like GFCI it makes absolute sense when you have muppets running about.
Teach…your churldens well… https://www.youtube.com/watch?v=EkaKwXddT_I
LOL.
I know what it is, it isn’t something from black magic, R-E-S-P-E-C-T…
https://www.youtube.com/watch?v=6_NEAEGeFIw
Or we could go back to Edison’s power plant every mile…
Yawn…
I have a DVD of an episode of “Danger Men” that’s all on the air2 company. Got it from the grandfather of one of the guys who used to work for the company.
I’m quite happy with our AU plug. Slanted pins so you can’t plug it in the wrong way, 220v and every socket has a switch on it.
I live in Canada (NEMA country) and I have to admit Aussie plugs are my favourite too, wish we had adopted them!
Anyway, the bottom line is: power to the people!
People in London probably pay 1500 quid in rent just for the room their plugs take.
But talking about safety, is there any statistical data on those ‘wonderful’ British monstro…plugs being such a boon to safety? I mean in practice rather than theoretical.
One aspect of the UK plug that has not been mentioned is that you cannot remove it by pulling the cord, you have to remove the plug top using the plug top.
Whether you consider that to be a safety aspect or a danger aspect is up to you.
In a movie or TV episode, has the BS1363 ever been used as a weapon? Safer against zaps = better melee weapon.
I’ve been very suprised to discover that a lot of extension cords or multi-plugs adaptors sold in France/Europe are reversing the live and neutral between the source (wall plug) and the end plug(s). Not only “noname” ones but also notorious brands like Legrand. Also a lot more internally do not respect the cable color regulation (blue = neutral).
That’s because mainland europe doesn’t do polarity, all plugs are reversible (you can plug them in ‘upside down’ since there is no up or down) and although installers have a convention when installing in homes there is no need to keep to it.
Uh oh.
Idea there is that there should not be devices for which the polarity matters for either function or safety. On the other hand various national standards do specify or recommend the polarity. Problem is that there are at least three variously formalized conventions for that:
– Phase left when the socket is facing the right way up (ie. ground pin on top)
– Phase right when the socket is right way up
– Phase always right without regard to socket’s orientation
(Current Czech standards says that the polarity should be consistent across whole installation, but only recommends phase being on left)
Another thing is that everything today has CEE 7/7 universal plugs, which are not polarized when plugged into schuko sockets.
This mess is the reason why new switched power strips typically switch both line and neutral.
I was talking about 3 pins ones with french earth connection, they can’t be reversed in France. But effectively CEE 7/7 can be reversed in other countries like Germany.
Quote from Wikipedia:
“To bridge the differences between German and French standards, the CEE 7/7 plug was developed. It is polarised to prevent the line and neutral connections from being reversed when used with a French CEE 7/5 socket, but allows polarity reversal when inserted into a German CEE 7/3 socket.”
Since these cords extension/multi-plugs are supposed to respect french regulations, i would expect them NOT to reverse polarity (and respect almost universal cables color conventions).
Polarity probably doesn’t matter for most devices, but reversing polarity can lead to have a switch cutting only the neutral and not the live, leaving live present in cables/devices, which is quite dangerous!
Yes the plug is seemingly forcing a polarization, but it’s only superficially since they also use the non-earthed euro plugs which can be oriented either way, plus as you say there are extension cords that ignore polarity, so in reality you can assume there is no polarity and you can assume you are safer with dual pole switches as Aleš Hakl points out.
In the UK something went wrong if the plug has the ‘neutral’ and ‘live’ reversed, but in many other countries it’s not a thing at all and you should therefore just assume there is a ‘wrong’ wiring in the circuit at all times.
Wikipedia has a list of plugs and if they are polarized btw https://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#Comparison_of_standard_types
There is a massive problem expecting polarity with the French standard, which is the fact that in Belgium they used the same socket. But reverse phase and neutral. Now given CEE 7/7 doesn’t provide polarity at all on Schukos (most common socket in Europe), all European equipment is either designed to not require a specific phase-neutral or are equipped with IEC 60309 plugs.
BS1363 doesn’t have any features of a high voltage connector because it isn’t one, its low voltage.
If you stand on a plug then you are a fool for 1) leaving things lying around on the floor 2) not looking where you are going.
Maybe people can’t see where they are going because it’s dark because the damn light is unplugged, and the plug is hard to find since it fell on the floor, in the dark.
unfortunately bs1363 plugs don’t just fall out of the socket. they are held very firmly.
perhaps you should think about the consequences of your actions before you commit to them fully.
Mum pulled it out earlier because she had to vacuum you see.
She was too busy to put it back.
No, the plug is easy to find. Just walk around till you step on it.
(But really, if it’s too dark to see what you’re stepping on, it’s just dark enough to consider why you don’t EDC a small flashlight. Or if you’re in the land of BS1363 plugs, a small torch.)
A “CEE 7” plug is commonly called a Schuko plug [HaD]; and it’s not “CEE 7”, it’s “CEE 7/4”.
“Schuko” /ˈʃuːkoʊ/ is a registered trademark referring to a system of AC power plugs and sockets that is defined as “CEE 7/3” (sockets) and “CEE 7/4” (plugs).
More here:
https://en.wikipedia.org/wiki/Schuko
Personally, I’d love to see the world standardise on something like the IEC C13 and C14 connectors (or possibly the C19 and C20 connectors for the higher current capacity). Wall outlets could easily be updated to include shutters over the connectors, triggered by the sheath entering the outer slot, or even the earth slot.
Obviously, I’d also like to see variations with a 90 degree bend, since that will also discourage people unplugging them by pulling on the cord, as well as keeping the cord close to the wall.
You have to be joking right?
Swiss Type-J plugs for the win! Small, safe, comparatively high power (10A + 16A Version @ 230V), one way to plug them in. Oh and did I mention there are 3 phase Versions of them, with almost the same size of Schuko ? Electric car AC charging would be quite OK if only these were in general use – 11 kW possible instead of 3.6 kW with Schuko.
Speaking of miswiring horror stories:
Couple days ago I was called to fix an old lamp. It was connected to Neutral and Earth inside the lamp. The plug was wired correctly. The wiring inside the lamp looked like it’s always been that way. Wonder how that could ever have worked.
Especially since the Schuko plugs you can fit in any orientation, making it possible to connect the lamp between Live and Ground, making all your appliances “Killer Apps” when you turn on the lights…
(what also baffles me is why the House’s FI-Fuse did not trip (if terminology isn’t correct, I mean the fuse that trips when it measures more than 100 milliAmps on the ground rail))
Why would that make all appliances unsafe? It only does when your earth wire has a high resistance.
Here where I live you usually have FIs only for the bathrooms. FIs don’t look at the current through the earth wire. They trip when the current through the live wire is different from the current through the neutral wire.
There’s one thing you forgot about UK plugs. They’re falling out of sockets which is infuriating
every single time I slightly pull a 2.5m usb charger wire, the charger falls out of socket.
Err… you might want to replace either the charger or the socket… that shouldn’t happen
Needs duct tape. But yeah, something needs replacing. All of the outlets could be from a bad vendor. Don’t bend the blades/pins like me. *JK*
I spent a few years in India as a kid.
We got lost on a hike in the hills once and ended up spending the night in a hydro electricity commission shed.
The power outlets were pairs of nails in the wooden frame with 240v on them.
In a nod towards safety, the nails were high up and not driven all the way through the frame to the tin cladding.
To turn on the light you hung a bayonet fitting with two rigid wires with loops to fit over the nails.
The water heater was a pair of metal plates (with a bit of cement sheet as an insulator) hung from the nails and dropped in a bucket.
I bet that building burned down not long after you left. One bird lands and ZAP! FWOOSH!
I’ve seen bad wiring but wow. I bet the lights had wire wrapped around the screw base and tape for good measure.
Ah, the UK three pin. It comes under so much fire for being big, but at least it’s flat. Hilarious how we never really decided on a standard, it’s way too late now.
“In a world moving towards moulded cables and plug-top power supplies it’s true to say that familiarity with the internals of your mains connectors is a less universal skill than it might once have been.”
Prior to about the mid-90’s in the UK you’d buy some appliance and then have to buy the three pin plug to go with it separately, so wiring a plug was pretty common knowledge. As noted in the article, the problem was that people would often just pick up or reuse one with a 13A fuse. Usually there was a choice of plugs with 3A, 5A or 13A fuse included – but they often just got the biggest – ‘cuz more amps is better!
UK consumer protection legislation now requires that domestic electrical goods be provided with fitted plugs (and so the correct fuse too).
If you push the plug in hard enough, you can normally persuade a British 3-pin socket to accept a 2-pin European plug.
I.e. you _can_ fit a round peg in a square hole. You normally have to use something like a biro in the earth pin to get the shutters open first.
Unfortunately the round pins are slightly larger in diameter than the square ones, so the receptacles in the socket end up getting bent open, This causes future British plugs to feel very loose, or in some cases, stop working completely.
If you spend any time at a British airport (e.g. Heathrow T5) then you’ll recognise this phenomenon!
Has anyone discovered inexpensive DC plugs and sockets, for off grid or modern DC grid scenarios? Andersson Powerpole is nice but more for batteries and not wall sockets. For now I plan to use XLR (rated to 16A per pin, commonly available, relatively inexpensive). Still nowhere near as inexpensive as normal US/EU AC plugs :/
Here is a draft for a wall socket for low voltage DC: https://github.com/OpenNanogrid/ON-socket
Interesting concept, and great execution. I wanted to mention that there already is a loose standard for 4-pin XLR plugs/sockets in power distribution.
3-pin has a few uses for power, albeit more seldom. The XLR 3 ones are generally reserved for audio signal distribution. In my mind, it would be unwise to mix the two – it opens the door to ambiguity of use.
Maybe I’m silly, but what’s wrong with one of the coaxial “barrel jack” standards? Just want more current handling? IMO it looks like a 5A barrel jack should cover 90% of use cases, and a higher-current, more expensive connector could be pursued for the other 10%. (Much like the NEMA 5-15 is used for 90%, but other connectors are used for electric ovens, dryers, welders, etc.)
XLR’s interesting, but a locking plug is both a blessing and a curse. When you trip over a skinny cord, do you want it to come unplugged, or risk permanent damage to the cord or whatever’s attached? There’s a reason locking connectors are common (at least in the US) for industrial high-current applications (where cable management is usually better, and cables are stout enough to resist tripping damage) but extremely rare for domestic use.
All this time, I never thought anyone actually gave thought to how to design a plug. I live in the US and it always just looked like someone picked the most convenient thing.
All NEMA 15A and 20A 125V and 250V receptacles contain 20A contacts. A 15A 125V plug has two parallel blades (| |) (neutral — grounded) blade wider. The safety grounding prongs are round and sufficiently close in size to the Schuko prongs to be interchangable (4.0 vs 4.8 or so). I use individual Schuko prongs when I need a safety ground without power. The 15A 250V plug uses the same sized blades (- -) as the hot 15A blades pointing at each other. The 20A 125V plug uses the 15A hot blade and the neutral blade is rotate to make a (- |) formation. The 20A 250V plug reverses the (| -) formation. The grounding prong prevents the 20A configurations from being plugged into the wrong voltage. The 20A receptacle configurations will accept 15A plugs because the slot that is changed for the 20A configuration in the plugs, is T shaped in the 20A version. The Canadian’s have their own 20A 125V receptacle that will only accept a 20A plug (it is without the T formation).
Double insulated devices in the US do not use the wide prong neutral blade because of the inherent additional protection in their design. The metal non-powered surface of a residential toaster in the US is never safety grounded and hence they all use two prong plugs.
As of the adoption of the 2008 National Electric Code (adopted by states at verious times) require all 125V receptacles installed in new construction and used a replacement receptacles in residential or locations specifically for small children be of the tamper-resistant, that is, shuttered and require the two flat blades be inserted at the same time to open the shutters. The grounding prong is not involved becuase it is not required for all applications. In potentially wet locations all 125V receptaces must be protected by a GFCI (Ground Fault Circuit Interrupter) set to trip on an unbalanced current of more that 5ma and less than 6ma. You can still be shocked with a cross-the-lines (hot and neutral) contact, but not from hot to ground and often not with neutral to ground. 250V receptacles of less that 30A capacity are rare in residentail settings (electric range and electric clothes dryer being the 50A and 30A exceptions).
The AUS/NZ plugs and receptacles are based on an early US design for a plug/receptacle with a safety ground prong which was of the same dimensions as the hot and neutral blades just slightly longer. This design was designated 15A 125V or 10A 250V with no change in configuration. The neutral and hot blades were (\ /). It might be possible for the safety ground to be plugged into the hot slot on the receptacle (I’ll try that some time.) The reason that AUS/NZ went with that design was that flat blades were easier and cheaper to make than round blades and the UK/GB plugs in use at the time of adoption had round prongs. The design did not catch on in the US because it was incompatible with the many existing parallel blade plugs. The NEMA plugs in the first para preserved that compatibility. The (\ /) blade configuration (along with a round grounding prong) lives on the NEMA 15A 277V plug/receptacle.