Internal wiring of USA v UK mains plug

Sleeves and pins... blades and wipers. They both sport similar life spans and contact mating particulars, and neither is a clear winner, and BOTH are used in higher power commercial scenarios. They are both proven winners for the industry.

As far as our "130V" (120V actually) 2 and 3 prong plugs and receptacles not having strain relief... they don't need it. If one remains within the specs for their use, the outlet/plug combo never sees any particularly high mechanical stresses placed on it. The bladed type actually fights mechanical stress in one plane far better than pins do without harming contact mating integrity over tens of thousands of stress cycles.

It is not a standard *Euro* plug and is only suitable for 2.5A

Its proper name is CEE7/16.

Graham

You take those with you when you travel? ;-)

But it won't fit a UK outlet due to the shutters - so not a true Euro plug.

--
*The fact that no one understands you doesn't mean you're an artist 

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

of

design

They are about the same as the IEC connector on the other end of most power cords. No big deal.

I think that the number of deaths from US-style outlets is minute. Electrocution and electrical fires result mostly from bad/old house wiring and faulty appliances.

Germany runs about 1 PPM annual risk of death from electrocution, with the USA closer to 2 PPM. That's not a lot of risk. I recall reading that the majority of electrocutions in the US are on construction sites, things like machines and ladders hitting high-voltage lines.

Really, cars are hundreds of times more dangerous than electricity, and cigarettes 10x again. If Europeans want to save lives, they should discourage smoking.

John

A timely comment. England starts a total smoking ban in enclosed public spaces and the work place at 0600 on the 1st July. And having used a train today noted my area service has banned smoking anywhere on their land - most of the smaller stations are surface with the platforms not enclosed so don't come under the law.

--
*Letting a cat out of the bag is easier than putting it back in *

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

There are also outlets used for room air conditioners. I have a 120V

15/20A outlet by one window downstairs and a 240V 20A (IIRC) outlet for the thru-the-wall AC. Stoves and clothes dryers may also have either a three pin ungrounded or four pin grounded outlet.

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  Keith

Am 30.06.07 16.28 schrieb Dave Plowman (News):

therefore I said "... but also for...." ,-)

Yeah well, the 'Islanders' always had to be slightly different from the rest of the world :-)

Am 30.06.07 14.04 schrieb John Larkin:

design

It's not necessarily the wall outlet itself I had bad experience with weakened contacts but much more those extremely poor designed extension cords with those 3 socket heads. And I also have seen so many messed up cable plugs, due to the lack of a decent mechanical support from the socket moulding and plug housing. Those often flaky cheapest style flat contacts bend very easily, especially if used on power cords connected to class II devices, which do not require a protective ground.

But also those 3-pin plugs come out of the wall socket quite easily, when a heavy rubber cable for an air compressor with that weird AWG format, probably coming close to a wire cross section of some 3.something mm², is connected to it. Despite the thicker, round third ground pin, the plug comes out very easily quite a bit, exposing dangerously the 2 spade contacts, so that I wouldn't want a toddler to be near it to put its tiny fingers across them. The extremely poor electrical safety is, btw., besides the far below suboptimal mechanical stability of the whole socket-plug system, my biggest critic of the US domestic 110V/15A power connector system.

Or think of a vacuum cleaner with roll-up cable, where you bend or even break the plug contacts quite easily while vacuuming around the room and putting some tension on the power cord, especially if the stress is applied under an angle

Boy I sure have, things got really cheap in the late 70s, about half the outlets in my 1979 house were bad, of course they also were the cheap bargain bin home center junk. You can get a pretty good outlet that will last a long time for about 2 bucks, or you can get a really crappy one that will wear out for about 75 cents. Guess which goes into most cookie cutter houses they're building these days?

I've heard of those, I don't recall ever actually seeing a 240V window AC unit though. AC in general is very rare around here and if people have it, it's normally central. Perhaps 0.1% of the houses have vertical casement windows that an AC unit will fit in, I suppose that would explain it.

Correct.

We're talking about oddballs in general though right? As I've said, in 99% of houses, you'll find one type of receptacle in all the standard locations, and it's the same type that's been used for decades. You'll also find a dryer outlet and a stove outlet in those houses that are not gas, and occasionally one of a few different oddballs for specific applications like air conditioners, compressors, welders, etc, but those are almost always added later and most houses lack them. I just don't understand why this would be confusing, it's made sense to me since I was a little kid, it's not as if we have a random mismash of different types in every room of the house. Any yahoo can do electrical work if they take some care to be neat and tidy.

design

of course, my bad. I was still thinking in terms of my accustomed european

230V system.

Having seen plenty of badly bent contact blades on vacuum, TV set, computer & monitor, power drill and other shop devices' power cords, I strongly disagree. Stuff is moved around, either in use or in off state and suddenly the power cord limits the mobility range. Depending on what kind of bull is pulling on the other end and he rarely does perpendicular to the wall with the outlet, those spades bend, simply because there is *no* strain relief *at all* in the US style socket/plug combo.

I can't comment on that, since I don't have reliable data, but simply asked, what about the other plain? And it also is much easier to have a slotted pipe type receptacle, with a steel tape spring surrounding it to guarantee, constant, long-term contact pressure for a round, mechanically sound, 5mm pin, which gives solid, equal contact all around its circumference.

I think it has a good reason that the later added third ground pin for the US system isn't of flat spade shape anymore, but strangely a round one now with, who would have thought it, 5mm like in the Schuko system as well ;-)

Am 30.06.07 15.01 schrieb Eeyore:

What is your definition of "standard"? The Euro plug was specifically developed already 1963 for insulated, class II, low power devices up to max. 2.5A, to fit universally all over Europe with the exception of the British BS1363 sockets. And it was adopted by the IEC in 1975 as plug C5 and as European standard EN 50075 in July 1990.

The European standard plug for higher currents is CEE7/17 contour plug, but also only for insulated devices, not requiring a ground contact.

The regular grounded Schuko plug system, CEE 7/4 and CEE7/7 is used as primary electrical system in the following countries:

• Afghanistan * Andorra * Deutschland * Estland * Finnland * Griechenland * Indonesien * Island * Italien / San Marino / Vatikanstaat (nicht norm, aber verwendet) * Kroatien * Lettland * Litauen * Niederlande * Norwegen * Österreich * Portugal * Rumänien * Rußland * Schweden * Slowenien * Spanien * Südkorea * Ukraine * Ungarn

Among others, these countries are using the CEE 7/7 compatible, ?french? system:

• Belgien * Frankreich und ein Teil der ehemaligen Kolonien * Monaco * Polen * Slowakei * Tschechien * Tunesien

So I would say, this rather long list of countries, stretching from the Atlantic to the Pacific and from the polar circle down to Africa, qualifies it as a "European standard" as well. Still not "European" enough?

But part of the EU so officially 'Euro'. Of course a Euro plug will fit a UK 'shaver' outlet.

--
*Why is the man who invests all your money called a broker? *

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

jakdedert wrote in news:e6yhi.8611$09.1625 @bignews8.bellsouth.net:

If an earth ground is not available, a GFI outlet should be installed at the beginning of the run and 3 prong outlets along the rest of the run.

The GFI will trip if a ground fault is present.

The outlets should be marked to indicate that a GFI is installed and that no earth ground is present.

I believe that this is much safer than using 2 prong outlets and meets code.

--
bz    	73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an 
infinite set.

bz+ser@ch100-5.chem.lsu.edu   remove ch100-5 to avoid spam trap

Right, things are different here then (UK). Its mostly the upper class with grand buildings that keep running historic installations. The less wealthy usually rent rather than own, and laws are much more stringent than those applying to privately owned dwellings. Capitalism backwards.

NT

I have (vertical) "casement" windows that are difficult to find window units for (even uglier to install). I also have two "window" units installed through the wall. One is a 25KBTU unit on a 240V 20A circuit, IIRC. The other is 7.5KBTU on a normal 120V 20A (15A outlet) circuit.

We normally only have two weeks of weather where an AC us useful (mine have run a total of 20 hours so far this year) so central AC is a bit expensive.

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  Keith

I never knew that, thanks.

I can bore the guys at the office with something else, now :-)

-- "Electricity is of two kinds, positive and negative. The difference is, I presume, that one comes a little more expensive, but is more durable; the other is a cheaper thing, but the moths get into it." (Stephen Leacock)

What's your mother got to do with it?

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JF