Internal wiring of USA v UK mains plug

[Rich Grise, Plainclothes Hippie]

For general purpose recepticle and lighting circuits, they are wired as
radial, but one fuse or breaker per radial circuit.


Yes, but not as much KWs are delivered to GP recepticles as there is in the
230V world, so less copper is used. Yes, that is at the expense of not
having 2.5 KW kettles and really funky coffee machines.

Larger appliances that need more power have their own dedicated recepticle
(or are hard wired) and circuit.

Receptacle.

They're more like tentacles than like testicles. ;-)

Rich Grise, Self-Appointed Chief
Internet Spelling Police. ;-)

 

[Richard The Dreaded Libertarian]

Sounds dodgy!
I've spent time in the US and Japan, and I have to say that those flat
blade sockets are an atrocious design. They suffer sloppy fit problems
very easily . Those countries don't seem to have switched wall sockets
either, which the Uk standard has, so you get more arcing if plugging
in live equipment

In the US, we know better than to do stupid crap like plugging in live
equipment.

Good Luck!
Rich

 

[Eeyore]

Ok, I'll conceed that one, but only 50%, after all, how many people
put a 16amp fuse on a .5mm cord?

No-one these days. A lamp for example will come with a plug already fitted and
probably a 3 or 5 amp fuse in the plug.

Graham

 

[Rich Grise]

Could someone direct me to pics of the 2 different types of plug/socket
system used in the USA to differentiate for medium and high power use, I
didn't even realise 220 or 240V was used residentially anywhere in the USA.

http://www.voltec-industries.com/nema_chart.html
https://www.hubbellnet.com/max_htm/tech_stuff/NEMA/front.html
http://nooutage.com/nema_configurations.htm

Hope This Helps!
Rich

 

[Eeyore]

In the U.K. you can buy appliances with 2 condoctor cords
with two plug pins that can usually be forced into U.K. outlets.
They are supposed to be for export to the E.U. but they are sold.

You can only force them into UK sockets with the aid of a large screwdriver down
the earth to open up the shutters. You're not supposed to do that.

The neat answer if you want to continue to be able to use them abroad is to use
one of these.

http://i17.ebayimg.com/04/i/07/20/fb/ag_1_b.JPG
http://cgi.ebay.co.uk/EURO-CONVERTO...ryZ96942QQrdZ1QQcmdZViewItem#ebayphotohosting

Graham

 

[Richard The Dreaded Libertarian]

It seems to be political why the US doesn't want to stop the sale of
unsafe accessories and the deaths that result.

Yes. Entirely political. We are the Land of the Free. If people want to
electrocute themselves, they have that right. Most of us in America are
grownups, who know better, and so don't need nanny queen to wipe our ass
for us.

Thanks,
Rich

 

[Eeyore]

Electric clothes dryer, stoves/ovens, and permanently installed air
conditioners are only available in 240 V versions. Also, larger sizes of
electric space heaters. The first three are probably more likely to be wired
in directly to a junction box than to use a plug/socket. There are several
incompatible types of 240 V plugs. All are huge, bigger than the UK plug,
and expensive.

Considering that the UK plug is good for 3kW, it's not really that large.

Graham

 

[Eeyore]

Well, much of the "fires" due to faulty wiring are because we have
*had* wiring as a general condition in most houses since the early
1900s, so after 100 years or so it gets a little tired, and when
overloaded can fail. Of course, 100 years ago, y'all had very nice
green lawns and gorgeous buildings.... but little electricity other
than the very wealthy.

I'd like to see some supporting data for that litle outburst.

Graham

 

[Eeyore]

I'm amazed. It presumably has some form of rubber insulation which will
have crumbled away years ago.

There's still some remnants of old rubber insulated wire in my house. It's in
quite good condition actually.

I imagine the current PVC stuff must be about 40-50 yrs old.

Graham

 

[Eeyore]

We have a bit of an issue with socket positions here. The great
majority of sockets are low down, and this doesn't stop the switches
being used. However new builds now require them high up for dubious PC
reasons, transforming trailing leads into trip hazards, which I think
will only cause more injuries and electrical faults.

Required ?

Since when was this . As you say, it seems to be a daft idea.

Graham

 

[Tam/WB2TT]

Its a known deal that 240v is safer than 120 for 2 main reasons.
1. The main killer is not electrocution, it is fire.

That is a sociologic/economic. not technical issue.

2. 240v gives much better discrimination between normal and fault
loads. IOW faults have less chance of tripping a breaker in time on
120v circuits.

I don't know what your load is. The US load per branch circuit is 1800 W,
before the circuit breaker in the box will trip. I think a GFI will trip at
10 microamps.

Tam

 

[Gary Tait]

Could someone direct me to pics of the 2 different types of
plug/socket system used in the USA to differentiate for medium and
high power use, I didn't even realise 220 or 240V was used
residentially anywhere in the USA.

http://nooutage.com/nema_configurations.htm

Some are used only in industrial and commercial situations though.

Not shown is the NEMA 10-xx configuration, which is used for the
aformentioned 120/240V appliances that use a neutral for chassis grounding
and as a return for internal 120V loads. They basically have angled hot
prongs with a straight or L shaped neutral prong (appropriately sized for
the load). FWIW, the NEMA 10-15 plug is exactly the same as a typical
Australian plug, less safety features.

 

[Dave Plowman (News)]

More likely cloth, not rubber...

If like UK wiring of that age, rubberised cloth. Which crumbles away. Uk
wiring was often lead sheathed and inside the sheath the insulation can be
perfect. But the ends exposed to air etc not.

 

[Gary Tait]

Leaving aside the joining wires/terminal blocks issue, on the subject
of the plugs and sockets, the UK one to me is superior in many ways.
1. fused plugs.

Not really needed, but could be a hazard due to mis-fusing.

FWIW, some lighting (especially holiday lighting) has fused plugs.

2. cord grip in plugs

Good aftermarket or factory moulded plugs have grips.

3. screw terminals in plugs -no wrapping wires.

As I said, good plugs don't have them, and wires can be twisted anti-
clockwise to wrap around screws.

4. ALL receptacles and plugs have earth pin.

That is a plus. As is the shuttered recepticals, the reason for the
earth pin on everything.

5. 3 prong design means a better fit (they don't waggle about at all)

I can't complain there. It is just easier to deal with two prong moulded
plugs, and they don't hold that bad in a decent recepticle.

6. much thicker pins - handle more current, do not bend, and seem to
resist arcing damage better.

In theory they could handle more, but are only limited to 13A by design.
the standard US plug design can do up to 20A.

7. switched sockets

Another plus for the UK (and Aussie) system.

 

[DJ Delorie]

http://www.voltec-industries.com/nema_chart.html
https://www.hubbellnet.com/max_htm/tech_stuff/NEMA/front.html
http://nooutage.com/nema_configurations.htm

Here's the one I use:
http://www.quail.com/nema.cfm

But yeah, TWO types of outlets? Come on, my house has way more than
just TWO types. Heck, I have at least two types of just 120v outlets.
I think I have four types of 240v outlets.

 

[Gary Tait]

[email protected] (Geoffrey S. Mendelson) wrote in

Cut me a break. Since around 1960 all of the outlets in the U.S. have
grounds.

In new installations maybe. There are still many hundreds of thousands of
two prong recepticals still installed, or incorectly refitted to three
prong recepticals.

 

[Gary Tait]

No you can't - legally. With the exception of shavers or toothbrushes
etc designed to fit a transformer isolated bathroom outlet, everything
must be fitted with a '13 amp' plug with a suitable fuse.

The appliances have a two prong cord, but a 13A plug with a dummy ground
pin (to open the shutters in the receptical). With the exception of those
that are inteded to be plugged into the batheroom shaver outlet, and those
sold in the black/grey market

 

[Gary Tait]

Really! I'm amazed... I thought Romex really had taken over the country
completely... does some locality think Romex is dangerous? Or they just
haven't updated their electrical codes to take it into account

They blame safety, but it is really the unions that force pipe, where pipe
is mandated. Not to mention certain type of buildings requiring conduit or
MC wiring.

 

[Gary Tait]

Most US-style fixtures have some plastic barriers between hot and
neutral and ground. If the wire was stripped too long the barriers
don't help... :-(.

That is improper though.

Stranded is the standard for line cords. I've never seen a line cord
with solid copper (maybe forbidden by code?)

At minimum it is bad practice to use solid conductor in place of a flex
cord.

Knob-and-tube was used through the 40's, maybe even 50's, in some
places in the US, and in most places is still allowed for repairs and
even extensions (if you can find the stuff! And no inspector ever
agrees with anyone on how to extend knob-and-tube using Romex!)

K&T is almost always solid copper.

 

[Eeyore]

I think a GFI will trip at 10 microamps.

!!!!!

Graham