Internal wiring of USA v UK mains plug

[krw]

Dont think I've ever seen pet chewed cords here, maybe different
checmicals get used in the plastic or something.

Ever see "National Lampoon's Christmas Vacation"?

120 0r 240 would kill either way.

240 is more lethal, though either is enough if they get a good chomp.

 

[Gary Tait]

What part of "if one remains within the specs for their use..." do you
not understand?

But when, in the hands of a lay person, does things stay within spec?

 

[John Larkin]

What part of "if one remains within the specs for their use..." do you
not understand?

If it's bent so much that it's hard to plug in, just bend it back. No
big deal.

John

 

[John Larkin]

Understood. I spent quite a bit of time putting GFI's in a house we bought
and are renting out. It was built in the late 40's and expanded several
times, some grounded outlets were installed but grounds were missing on
several. Older parts of the house are on an aux breaker box.

Figuring out what fed what was fun.

Why don't houses come with schematics?

John

 

[jakdedert]

Understood. I spent quite a bit of time putting GFI's in a house we bought
and are renting out. It was built in the late 40's and expanded several
times, some grounded outlets were installed but grounds were missing on
several. Older parts of the house are on an aux breaker box.

Figuring out what fed what was fun.

That's why I just replace the two-prongers as they wear out. New
grounded circuits are home-runs from the breaker box, with new cable and
a new breaker.

jak

 

[[email protected]]

You'd have to explain that. Most of the old round pin sockets were
switched - unswitched was a short lived fashion with 13 amp stuff. At
least in my experience.

The old round pin sockets were far more likely to be overloaded, though.

Round pin systems did not consistently have good contact arrangement,
leading to frequent bad connections between plug & socket, producing
the same type of damage as occurs with unswitched sockets.


NT

 

[Geoffrey S. Mendelson]

Round pin systems did not consistently have good contact arrangement,
leading to frequent bad connections between plug & socket, producing
the same type of damage as occurs with unswitched sockets.

Flat plugs came about because of Thomas Edison. He hated Tesla and
refused to use anything but direct current in his electrical systems.
His electrical service company, which supplied New York City,
started out as DC and the large spring loaded plugs were needed.

The originaly were made of two leaf springs, probably brass.

Geoff.

 

[Dave Plowman (News)]

Round pin systems did not consistently have good contact arrangement,
leading to frequent bad connections between plug & socket, producing
the same type of damage as occurs with unswitched sockets.

I'd say it depended on the quality of the fitting - given most plug/socket
arrangements have round pins. Including the heavy duty BS4343 type.

 

[Wolfi]

Am 02.07.07 19.20 schrieb Spurious Response:
You're talking about this IEC (http://de.wikipedia.org/wiki/IEC_60309) power
connector, rated from 16A up to 250A @690VAC? ;-)
But it also uses round pins, not flat ones.

Yes. Thick, flat blades. Leaning toward square even, but not quite so.

Or should you mean that type, which is used for computer monitors and -power
supplies?
If so, then you surely noticed the lousy Ampère rating of mere 10A for it,
which is just 2.3kW, rather than the 3.68kW which you have with a 16A
connector system?

The main reason is that the designers of that chassis end (entry
module) of that chassis connector system wanted large, round nosed
pyramidal points on those strong, flat blades so they could act as good,
repeatable "lead-ins" for the "otherwise only held in by the rubber
squeeze" connector. Also, flat blades do maintain larger swept area of
contact (and therefore safer current carrying capacity) longer than pins
and sleeves after repeated disconnect reconnect cycles. That plug design
was meant for molded on plug assemblies.

Jeez, just think of how huge some strain relieved, metallic, heavy duty
device would be on the back of all our gear over the years.

That's not required at all, but all those connector standards, Schuko, Euro,
IEC 60309, IEC 60906-1 and the forementioned 3-contact socket/plug system used
for computer monitors and SMSP have the removable parts case dive into the
fixed mounted one, taking off mechanical stress from the pins and burden it
onto the housing.
And exactly this point is *not* true for the U.S. style connector system and
this is one of the reasons, why I have quite a low opinion of it.

That was one more benefit of the flat bladed design, was narrower
overall plug size for any given ampacity and voltage compared to what
would have been required for round pins.

Well, it must have some reason that the international standard 230 V household
plug system, specified under IEC 60906-1, uses round pins as well, not flat
ones. http://en.wikipedia.org/wiki/IEC_60906-1

 

[Wolfi]

Am 02.07.07 19.07 schrieb Spurious Response:

What part of "if one remains within the specs for their use..." do you
not understand?

I don't know. Apparently those specs are either missing completely on those
devices' power cords I came across so far, or they are written so tiny, that
not a single one of their owners could read them either.

And, If I plug in that forementioned air compressors power cord and it comes
out of the socket again just by the weight of the cable pulling on it, which
spec applies for it then?

It just prooves my point that it is a poor system having all the weight/pull
on a cable being put on the electric contacts rather than to the largest
degree on the housing.

 

[Wolfi]

Am 02.07.07 21.35 schrieb John Larkin:

If it's bent so much that it's hard to plug in, just bend it back. No
big deal.

Oh yes, it easily becomes a big deal as in case of an electric floor heater.
Some moron in the past had moved it around so violently while being plugged
in, that both contacts had been bent to at least 45° off direction befor it
came out of the socket and when I tried to put them straight again, one of
them broke off. I had quite a hard time to find a screw on replacement plug.

 

[Spurious Response]

Why don't houses come with schematics?

John

The number of complete dopes that ignore the "No User Serviceable Parts
Inside" notice and open their consumer product up anyway is already
staggering, and some of those still come with schematics.

I am sure this would cause an increase in house fires around the
nation.

 

[Spurious Response]

You're talking about this IEC (http://de.wikipedia.org/wiki/IEC_60309) power
connector, rated from 16A up to 250A @690VAC? ;-)
But it also uses round pins, not flat ones.

No, silly. He was talking about the STANDARD US 120V IEC cord used on
nearly everything made these days, from dongles to 70" FPDs.

http://www.coleparmer.com/techinfo/techinfo.asp?htmlfile=IEC320ModularPowerCordsAndPlugs.htm&ID=346

 

[Spurious Response]

If so, then you surely noticed the lousy Ampère rating of mere 10A for it,
which is just 2.3kW, rather than the 3.68kW which you have with a 16A
connector system?

If I do not need 16 A power feeds as a result of not having any 16 A
power requisites, then why would I need a 16 A cord and receptacle
system?

 

[Spurious Response]

Well, it must have some reason that the international standard 230 V household
plug system, specified under IEC 60906-1, uses round pins as well, not flat
ones. http://en.wikipedia.org/wiki/IEC_60906-1

That thing has ONLY been planned for adoption by BRAZIL!

You say "international standard", but the part of that that makes it
"international" is the fact that an international organization published
it. Other than that, it is quite obscure.

There are many reasons for choosing round or flat contacts. There are
many connector systems... many different connector system designs.

One factor is temperature.

Here is a great place to get some power cord trivia:

http://www.accesscomms.com.au/reference/IEC320.htm

That is just the 320 section.

 

[Spurious Response]

I don't know. Apparently those specs are either missing completely on those
devices' power cords I came across so far, or they are written so tiny, that
not a single one of their owners could read them either.

So, now you want to convince everyone here that the force needed to make
those blades bend was within the operational specs for the connector
system?

Use a little common sense, or don't be a dork, take your choice.

 

[Spurious Response]

And, If I plug in that forementioned air compressors power cord and it comes
out of the socket again just by the weight of the cable pulling on it, which
spec applies for it then?

If you are plugging some bent up plug into a power socket, you are an
idiot for not servicing the plug before using the product it was attached
to. Oh, and if you are seeing perfectly normal plugs coming out of an
outlet, YOU need to service the outlet.

How's that for a spec, dipshit? or... How's that for getting
yourself spec'd, as a dipshit, dipshit?

 

[Eeyore]

If I do not need 16 A power feeds as a result of not having any 16 A
power requisites, then why would I need a 16 A cord and receptacle
system?

The standards aren't set around one person's requirements.

Graham

 

[Wolfi]

Am 03.07.07 19.42 schrieb Spurious Response:

If I do not need 16 A power feeds as a result of not having any 16 A
power requisites, then why would I need a 16 A cord and receptacle
system?

Because initially we had been talking about wall outlets and according plugs,
with flat (US, UK) or round (most of Central Europe) contacts and those
connectors are rated 15A/130V (US) or 16A/250V (Europe).
So when talking about alternatives, we have to stay in the same ratings range.

 

[Wolfi]

Am 03.07.07 19.40 schrieb Spurious Response:

No, silly. He was talking about the STANDARD US 120V IEC cord used on
nearly everything made these days, from dongles to 70" FPDs.

http://www.coleparmer.com/techinfo/techinfo.asp?htmlfile=IEC320ModularPowerCordsAndPlugs.htm&ID=346

Ah, that's what I reckoned, cords with the *international* standard socket
type IEC 60320-C13 /max. 70°C/10A (and -C15 /max. 120°C/10A or max. 155°C/16A).
http://en.wikipedia.org/wiki/IEC_connector
http://de.wikipedia.org/wiki/Gerätestecker

And there is also our famous Euro socket for small devices according to
protection class II, the type IEC-60320-C7, which normally is the device sided
end of the 2.5A Euro wall plug we had discussed earlier on.

But they all have in common, that they provide excellent user protection
against touching of live parts *and* they all plug mechanically *into* the
counterpart with their housing, hence guiding mechanically stress away from
the contacts and into the housing.