AudioMasters
 
 User Info & Key Stats   
Welcome, Guest. Please login or register.

Login with username, password and session length
September 09, 2010, 05:21:09 AM
71080 Posts in 7446 Topics by 2268 Members
Latest Member: dino3daudio
News:       Buy Adobe Audition:
+  AudioMasters
|-+  Off Topic
| |-+  OT Posts
| | |-+  British mains plugs
  « previous next »
Pages: [1] 2 3 4 Print
Author
Topic: British mains plugs  (Read 4087 times)
« on: November 25, 2009, 04:59:59 PM »
Bert Offline
Member
*****
Never too old to do new things Posts: 124



Recently I bought a pair of new active monitors. Since they were designed in Britain but manufactured in China, and delivered by a german supplier, they came both with British mains cables and german ones. Neither fits to my domestic outlets and the cables had to be retrofitted. At this occasion I noticed that a British plug rated for 5 Amps takes 50 mm of space, while my Swiss plugs take only 20 mm of space and are rated for 10 Amps. The difference is that the British plug is fused,  and can also serve for murder, while my domestic ones are not. I started to count the plugs under my table serving all computers, peripheral devices, amplifiers ........ and ended above two dozens taking about 1 m of plugged noodles. Extrapolating this further I came up to about 2.5 m under a British desk. I am really not making fun of my British friends - but how do handle this ?
Logged
Reply #1
« on: November 25, 2009, 05:39:46 PM »
Graeme Offline
Administrator
Member
*****
Posts: 2247

WWW

I'm not sure I fully understand the question.  Do you mean the British plug takes up more space than the continental/US ones?  In which case, yes, they do.

However, there are some serious advantages to the UK system;

1 - Although it might not be connected (and would have no need to be, if the equipment is double isolated) there is always an earth/ground connection available.

2 - The earth/ground pin is longer, thus ensuring the equipment is earthed/grounded, before any power is applied.

3 - The very nature of the UK plug means it cannot be reversed in the socket, hence (assuming the correct connections have been made internally) live is always live and neutral always neutral.

4 - As you have noted, there is an internal fuse.  This means that each plug can be fused at a rating consistant with the device it is attached to (although I would be the first to admit that few users actually do this, but that's not a criticism of the basic design). 

5 - The maximum rating is 13A (at 240 v of course) - more than adequate for virtually any domestic appliance, other than an electric cooker.

6 - Following on from Nš5, the same plug can be used throughout the house.  Unlike the continent, where there are two very similar designs (rated at different capacities) that will actually mate with each other, but not very effectively - and potentially dangerously.

Being UK born and bred, but now living in Spain, I'm appalled at the liberties the Spanish take with electricity and the shoddy construction of many of the local plugs and sockets.  For reliability and safety, give me the UK system anytime.


If I have any complaint at all about modern trends in electrical equipment, it is the proliferation of wall warts that we now have to endure.  They invariably take up the space required for two or three normal plugs and often result in even more wires trailing around.  I have loads of stuff which require a wall wart supply and although I always label them (so I know what belongs to what) they do get moved around and then I have to go on a hunt for the missing item.

Of course, the manufacturers love them , as it removes the necessity for them to design and build a proper supply inside the equipment and they no longer have to worry about the various standards that exist throughout the world.  But, for the end user, I think they are nothing but a problem.  I find these things a real PITA and I would be only too pleased to see them banned!
Logged

Reply #2
« on: November 25, 2009, 07:16:31 PM »
Havoc Offline
Member
*****
Posts: 1131



I don't really agree with that Greame. The UK plug is a remains from the victorian age that has outlived its need. And then you even forget to add that there is a switch at each outlet.

1. If a piece of equipment is double isolated there is no need for earth and then you can use type C. Doesn't pose any issue. So why add a piece of wire that can only add to confusion and potential problems if you do connect it?

2. Ok, a point. Note that most other european sockets also offer this feature but it isn't visible, the contact in the socket is nearer the frontplate for the earth connection.

3. debatable. The only ones that are reversable are type C (but it is double isolated), type F and L. So most plugs are polarised. And I don't know much installations where the polarity is done according to the books.

4. rather a problem than an advantage. How do they do this with IEC sockets? At the office when we move gear we leave the cords and only move the equipment. And what is the use of 3 fuses in line (the equipment, the plug and the box)?

5. most outlets here can handle 16A without a problem and in far smaller space.

6. don't know where you get the idea that they don't mate securely. There is only a single socket and that is the grounded 16A one. You can fit a type C in that without any problem. It is designed to work that way.

I don't think overengineering is a virtue. About time we do away with earth I think. It isn't a problem double isolating anything and the result will be both safer equipment, safer installations because less faults in connections and cheaper with less wire.

Agreed about the warts however.
Logged

Expert in non-working solutions.
Reply #3
« on: November 25, 2009, 07:26:22 PM »
SteveG Offline
Administrator
Member
*****
Posts: 9635



I've seen enough problems with equipment in metal boxes that are supposedly fully isolated but in fact are nothing of the sort to think that the UK wiring system (which is not  Victorian - back in the early 20th Century we had a much more dangerous system more like some of the Continental ones) as it is is a whole lot safer than any of the Continental, or come to that, American ones.

Like Graeme I suspect, I'd rather live with a slightly over-engineered system than die by an overtly dangerous one - which that Swiss system certainly is.

http://www.leadsdirect.co.uk/technical/mainswiring.html
Logged

Reply #4
« on: November 25, 2009, 09:16:28 PM »
ozpeter Offline
Member
*****
Posts: 2289



When I moved to Australia from the UK I was amazed at the way power points are located, legally, right next to bathroom basins here.  But on the other side of the coin, DIY electrical work is banned, whereas I think in the UK you can do what you like in your own home in that respect.

The size requirements for electrical outlets these days is now influenced by the need to accommodate "wall warts" of sometimes prodigious size.

As for what's beneath my own desk here - well, it's a mess of UK and Australian mains cabling - it was easier to put plug-in adapters on some UK distribution boards and connect my UK-origin stuff to those rather than change all the plugs.  But as stuff gets updated, I'm gradually saving some space by the increased proportion of move svelte Australian connectors.
Logged
Reply #5
« on: November 25, 2009, 09:39:15 PM »
Bert Offline
Member
*****
Never too old to do new things Posts: 124



I was almost sure to open a can of worms but I did not expect the worms to come out so fast. My question was not really serious and my concern was simply as where to take so much space for the usual number of apparatus a technical person in common needs. It was not my aim to critisise the system as such, except the plugs looking overly heavy to me.

Obviously, I have to correct my British colleagues with respect to the Swiss system. Refering to Graemme's points I can asure that ALL of these are met by the Swiss system also. The only exception is that the maximum rating is 10 A, which is also the rating of the fuse or safety switch at the mains board. The disadvantage of the smaller plugs is in fact the increasing use of wall warts which often overlap the space of the adjacent outlet and make it unusabele. I know that some other continental systems have deficiencies I would not like to live with myself. Therefore I strongly reject the Swiss system to be rated as dangerous. Anytime there is need for more power, the idea of our system is to use a 3-phase connection. That is common for kitchen stoves, laundry machines ......... Apart from that I would like to point out that some time ago, there was an international  harmonising effort that brought up the original 220 V on the continent to 230 V in 2 V steps per year and at he same time the British 240 V were brought down by the same steps. At least in my place the voltage is between 228 and 232 V. I think that holds for Britain too.
Logged
Reply #6
« on: November 25, 2009, 11:50:12 PM »
SteveG Offline
Administrator
Member
*****
Posts: 9635



Refering to Graemme's points I can asure that ALL of these are met by the Swiss system also.

Graeme didn't mention one point - and unless it's true of the Swiss system (which I rather doubt) then it's still dangerous as far as I'm concerned - like the majority of other continental sockets. And that is the shuttering system that's inherent in UK sockets. The earth pin, because it sticks out further, activates a shutter system for the other two connectors which means that bare wires can't be poked straight down into the sockets. Also the current design of the pins on the plugs (which is now similar in the Euro ones) means that you can't accidentally get a shock from them when inserting them, and that's a failing with a lot of other connectors. It's also worth noting that the relatively wide spacing of the pins, and the relatively substantial earth pins makes for a far more stable connector than some other systems, although a fully implemented round continental one isn't bad either.
Logged

Reply #7
« on: November 26, 2009, 01:58:21 AM »
Amrad Offline
Member
*****
Posts: 34



When I moved to Australia from the UK I was amazed at the way power points are located, legally, right next to bathroom basins here.  But on the other side of the coin, DIY electrical work is banned, whereas I think in the UK you can do what you like in your own home in that respect.

Not since January 1st 2005, you can't, with some exceptions! For a brief overview of the new regulations, see this PDF article: Rules for electrical safety in the home.

Refering to Graemme's points I can asure that ALL of these are met by the Swiss system also.

Graeme didn't mention one point - and unless it's true of the Swiss system (which I rather doubt) then it's still dangerous as far as I'm concerned - like the majority of other continental sockets. And that is the shuttering system that's inherent in UK sockets. The earth pin, because it sticks out further, activates a shutter system for the other two connectors which means that bare wires can't be poked straight down into the sockets

There are some UK sockets which don't use the earth pin to activate the shuttering. Instead, the shutter is operated by the other two pins. The shutter is so designed that, as the plug is inserted, the pressure on the shutter causes it to rotate about its centre, moving out of the way of the pins.

It is very easy to insert bare wires into sockets where the shuttering is operated by the earth pin, and not much more difficult with the other type. All it needs is a suitable screwdriver (or an earth pin removed from a plug!) to push the shutter actuator in the socket's earth connector, allowing insertion of the wires! Removal of the screwdriver or earth pin, allows the shutter to partially close, clamping the wires, though not very effectively.

Regards,

Dave.
Logged
Reply #8
« on: November 26, 2009, 06:01:42 AM »
Graeme Offline
Administrator
Member
*****
Posts: 2247

WWW

I wrote a long reply to Havoc's post - basically refuting most of his arguments - but the site went down while I was writing and I then lost the post when trying to upload it!  I really don't fancy doing it all again so, suffice to say, I don't have a problem with over-engineered products.  In fact, modern 'value engineering' tends to leave me a little concerned about overall efficiency and long-term reliability.

A case in point:

Many of you may have heard about the bad floods in the Cumbria area of the UK.  These floods totally demolished a number of bridges that were less than 100 years old.  On the other hand, the Roman bridges (undoubtedly 'over-engineered' by todays standards) are still standing and in use.
Logged

Reply #9
« on: November 26, 2009, 08:26:40 AM »
Bert Offline
Member
*****
Never too old to do new things Posts: 124



No Graeme, your post seems to be complete. For some British members, it seems to be important to proove that the British system is the only safe one. May they keep their pride. BTW: The shutter system is known in Switzerland as well, but it is only an OPTION. However then, the shutter can only be opened by pressing ALL of the 3 contacts. As far as I remember from my visits on the isle, NOT ALL of the outlets had the shutter system.
Logged
Reply #10
« on: November 26, 2009, 09:20:04 AM »
SteveG Offline
Administrator
Member
*****
Posts: 9635



No Graeme, your post seems to be complete. For some British members, it seems to be important to proove that the British system is the only safe one. May they keep their pride.

No, it's just a  relatively safe system - I'm sure that there may be others in existence. Amrad's statement about being able to circumvent the shutter system misses the main point of it completely; almost any  system can be circumvented if you make enough effort, but one thing that the UK system achieves though is to make it rather harder for young children to force things into sockets, which was a major reason for the shutter introduction. Despite his claims, it's not easy to force wires into contact with the mating parts of sockets - the wires would need to be pretty stiff, and make contact on the sides to work, and ensuring that means quite a bit of effort, as these parts are recessed about 2cm.

My point isn't that the UK system is good (I think it's pretty average actually, certainly in its original form*) but that most other countries have a rather worse one - which they demonstrably do.

Quote
BTW: The shutter system is known in Switzerland as well, but it is only an OPTION. However then, the shutter can only be opened by pressing ALL of the 3 contacts. As far as I remember from my visits on the isle, NOT ALL of the outlets had the shutter system.

Optional  safety? Hmm.... In the UK there are still remnants of the previous system (used four different sizes of round pins in four different sockets!) lurking, and indeed half of the system is still in 'official' use in installed stage and studio lighting systems. Domestically though, use of that system is mercifully rare, and invariably it's only found in properties that are way  overdue for rewiring.

* One of its major problems, certainly when it was introduced was that it is essentially a 'flat' system, and that meant that it was possible (and I've seen this happen a couple of times with serious consequences) for a child to wrap a hand right around the plug, fingers in contact with pins, whilst pushing it into the socket. Since then, and as a direct result of many instances of this, the shrouded pins were introduced, meaning that contact was only made when the pin was sufficiently far into the socket for no possibility of contact. Inherently, any system where the socket is recessed and pins shrouded eliminates this possibility completely. My only real concern with the continental system (which sort-of addresses this) is that shutter arrangements aren't particularly good - if they are there at all.

Logged

Reply #11
« on: November 26, 2009, 12:08:36 PM »
Havoc Offline
Member
*****
Posts: 1131



Safety shutters are required here as well. You cannot buy anything else. They are operated by the pins of the connector, the earth is a pin sticking out from the socket. They are so safe that if they have been more than a year under your desk you cannot even open them anymore by just sticking in a connector. So yes, they are a problem but only in the safe sense. You will still find installed older sockets without shutters around but anything installed the last 20 years will have those things.

To address the concern about touching live pins, the pins do not mate with the contacts unless the connector sits inside the recessed socket. No way to get your fingers at powered pins. And at that time the earth connection is already made. And before someone mentions the 2-pin connector, this one has shrouded pins.

So will those brits that keep bashing european systems please go out and study one before continuing? Not just looking at a connector but also the mating socket. After all it is a system.
Logged

Expert in non-working solutions.
Reply #12
« on: November 26, 2009, 02:59:03 PM »
SteveG Offline
Administrator
Member
*****
Posts: 9635



So will those brits that keep bashing european systems please go out and study one before continuing? Not just looking at a connector but also the mating socket. After all it is a system.

I've studied quite a lot - and in several different countries as well. And all I can say is that the standards of sockets you find varies considerably. Best ones I found were on a cruise liner - although that had only just been refitted. I was going to say something about what I found in rural France, but that would only provoke more comments - probably along the same lines as the comments about remnants of the old UK system, although I get the impression that the French might not care as much about this as they should... The ones in Norway were okay generally, as were the ones in Iceland.
Logged

Reply #13
« on: November 26, 2009, 03:11:57 PM »
Graeme Offline
Administrator
Member
*****
Posts: 2247

WWW

No Graeme, your post seems to be complete.

No - my second post failed entirely Smiley .

For some British members, it seems to be important to proove that the British system is the only safe one. May they keep their pride.

That's not really the case.  Having lived with the UK system, the USA system and the Spanish one, I know which I consider to be the safer.  This has nothing to do with national pride, just practicalities.
Logged

Reply #14
« on: November 26, 2009, 03:14:59 PM »
Graeme Offline
Administrator
Member
*****
Posts: 2247

WWW

So will those brits that keep bashing european systems please go out and study one before continuing?

I don't need to study it, I live with one.  I have also lived with the UK and USA systems, so my comments are based on use, not theory.

Not just looking at a connector but also the mating socket. After all it is a system.

However, not as good, IMO.
Logged

Pages: [1] 2 3 4 Print 
« previous next »
Jump to:  

Powered by MySQL Powered by PHP Valid XHTML 1.0! Valid CSS! Ig-Oh Theme by koni.