On 16 Jun 2008 08:19:12 GMT, firstname.lastname@example.org (Andrew Gabriel)
There is a list with images of all the EIA receptacles.
There are higher voltage models, and higher current models, and euro
models. About 40 different plug/connector combos.
I don't have the link handy right now, but I dug through this sheet
about a year or so ago.
Going with the standard is the way to go. anything else handcuffs your
available sales region(s).
The Germans blew it all up ?
I have always said Europe and Japan got a kick start after the war
because they had to build new infrastructure. We still had all of our
old "plant". (particularly the "big iron" tank factories) How else can
you explain why cars in the US didn't advance much from the 30's until
the rest of the world kicked our ass into changing.
I suppose you are right, we do have a lot of homes wired for a "60a"
world and trying to live the American "200a" lifestyle. That does tend
to get back to my "extension cords and cube tap" theory.
Precisely why I'd like to see some reliable statistics.
Strange, because they're more electrical appliances in use at the end,
especially portable ones.
That's surprising. I wouldn't be surprised at higher electrocution
figures since the US has more swimming pools per capita, and the code
for electrical outlets in bathrooms anf kitchens has only recently been
Was it the increase in "do it yourself" wiring? I hope it wasn't the
inspectors getting electrocuted! :-)
There is a proposed US code change to require "arc detecting" circuit
breakers in many areas. This sounds like a good idea, until one sees
the problem with implementing such a device. GFCIs, (RCDs), are now
common, and and are required in dangerous areas by the new codes.
"Use and regulations differ widely from country to country. In Europe,
the UK is the only country that does not mandate the use of RCDs
(however this is due to change in July 2008 for most new installations).
In contrast, Germany requres the use of RCDs on ALL sockets up to 20A
which are for general use. This rule was introduced in June 2007 (DIN
VDE 0100-410 Nr. 411.3.3). In the U.S., the National Electrical Code
requires GFCIs in bathrooms, kitchens, garages, outdoor areas, crawl
spaces, unfinished basements, near wet bars, swimming pools, and spas in
I don't mean to re-ignite, (no pun intended), the 240V vs 120V argument!
If the initial data capture is inaccurate, there are none to be
had no matter how you process the data subsequently.
There was a noticable effect around 1990, which was put down
to a significant increase in HiFi/TV/Video appliances. However,
the general trend would appear to be safety improving faster than
the rate of increase of appliances (although that's a gross over-
No. DIY wiring has always been very popular here. The change
in the law made it much more beurocratic, and expensive, to make
safe DIY changes legally, and encourages temporary and less well
designed changes. There was no evidence that DIY wiring was
responsible for any of the incidents. Indeed there was much
evidence that the incidents resulted from _not_ making changes
and improvements to wiring when they were required. So a law to
encourage temporary and less well designed changes, and to dissaude
you making improvements properly, had exactly the effect many of us
predicted it would, but much more drammatically than even we imagined
I was reading that recently New Zealand reversed similar
legislation they have had, and saw safety improve. I'm not
familiar with local issues with New Zealand wiring, but given
what we predicted and have subsequently seen here, that comes as
no surprise to me.
I have to say that seems to me like the wrong solution to your
arcing problem. I think you should look at the design and quality
of your wiring accessories compared with other countries at
similar economic levels. This just isn't a problem in most
countries. An arc fault detector is a sticky plaster, and you
would do better to solve the actual arcing problems, IMHO.
Do bare in mind that over half of Europe pays no attention to
their wiring codes at all, so it doesn't really matter what they
say. Our wiring regs in the UK have been very good for years (and
have been adopted by some other countries too). However, the newest
(17th) edition you refer to above has gone rather commercial now with
companies managing to force their products into it without the considered
risk and benefit analysis which made it a highly respected set of regs in
the past. The 17th Edition regs claim to replace the 16th Edition in July
2008, but their legal force is via building regulations, which still
explicitly require use of the 16th Edition for homes. So currently this
is all in a mess, because the processes have been taken over by politicians
and commercial concerns with their own agendas, whereas it used to be
handled by real engineers who understood wiring and what safety and risk
[email address is not usable -- followup in the newsgroup]
They really ought to be grounded too. Years ago I had a halogen torchier
in my office. I could swear I got a tingle several times when touching
it, then one day I pulled the monitor cable off one of my PCs and in
doing so the metal connector shell brushed the lamp and POW! It tripped
the circuit, burned a chunk out of the connector, and left a small blob
of melted metal on the lamp. I did some investigating and found that a
wire had chafed where it runs through the threaded tube up at the top
and the entire lamp was hot.
On Tue, 10 Jun 2008 09:33:30 -0400 email@example.com wrote:
|>why we are preferring 3pin plugs in some devices (eg.in ups,extention|>boxes...) and why we are preffering 2pin plugs in some devices(eg.in|>ordinary night lamps)?
| Anything with a metal case probably should have a ground pin, although
| it is not always true.
The way a device is used might also factor in. Aside from those using a
wall wart power supply with a definite low voltage barrier, computers are
devices that humans regularly operate (even though the keyboards tend to
be make of plastic).
The way the wiring is done internally might also factor in. A device that
has a greater risk of creating a path from the hot wire to the case, or is
more subject to potential damage internally, or can get wet, might need a
But I see many exceptions to a lot of these. A friend has an electronic
organ that directly connects to AC power with a 2-conductor cord that is
a lot like a shaver cord. Many kitchen appliances still use ungrounded
I think a lot of it is legacy, too.
A neighboor of mine, when I was in grade school, was wiring up an antenna to
a new 2nd TV. It kept blowing fuses when it was turned on. He had the TV
repair guy come check it out. After blowing yet another fuse he was trying
thingswith it and notice it was OK with the antenna disconnected. So he
went to put the antenna back on while it was on and got to see a nice bright
arc and blew another fuse. Turns out the 1st TV was the culprit and the TV
antenna was "hot" and sufficiently isolated from ground that it didn't draw
enough to blow a fuse or burn out the twin line. The 2nd TV had the antenna
line grounded. Reversing the plug on the 1st TV was the workaround. As far
as I know, they left it like that. This was in the 1960's.
I had an old shortwave radio my grandmother gave me that would have its antenna
lead "hot" when the plug was reversed. My grandfather gave me an old capacitor
tester when I was getting interested in electronics. I got to feel what 120V
was like one time when I touched it while barefoot in the basement.
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| by the abuse department, bellsouth.net is blocked. If you post to |
There three classes of protection against electric shock listed in IEC/EN
See extracts from IEN/EN 60950-1 below:-
Class I - equipment where protection against electric shock is achieved by
- using BASIC INSULATION and
- providing a means of connection to the PROTECTIVE EARTHING CONDUCTOR in
wiring those conductive parts that are otherwise capable of assuming
VOLTAGES if the BASIC INSULATION fails
NOTE CLASS I EQUIPMENT may have parts with DOUBLE INSULATION or REINFORCED
The typical electic stove, kettle etc used in Europe with a three pin plug.
Class II equipment in which protection against electric shock does not rely
on BASIC INSULATION only,
but in which additional safety precautions, such as DOUBLE INSULATION or
INSULATION are provided, there being no reliance on protective earthing.
A typical electric shaver, hair drier etc, with a two pin European plug (no
Class III equipment in which protection against electric shock relies upon
supply from SELV CIRCUITS
and in which HAZARDOUS VOLTAGES are not generated
NOTE For CLASS III EQUIPMENT, although there is no requirement for
protection against electric shock, all other
requirements of the standard apply.
Typical battery operated equipment.
insulation to provide basic protection against electric shock.
independent insulation applied in addition to BASIC INSULATION in order to
reduce the risk of
electric shock in the event of a failure of the BASIC INSULATION
insulation comprising both BASIC INSULATION and SUPPLEMENTARY INSULATION
single insulation system that provides a degree of protection against
electric shock equivalent
to DOUBLE INSULATION under the conditions specified in this standard
NOTE The term "insulation system" does not imply that the insulation has to
be in one homogeneous piece.
It may comprise several layers that cannot be tested as BASIC INSULATION and
Hope the above helps.
Leeds lad in exile
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