Mike Barnes wrote in message ...
The Americans, being a resourceful people, have a simple solution to
that problem: Most of them don't have electric kettles. With very few
exceptions, they boil their water in a pan on the hob.


I think you're out of date, they now use the microwave!

Regards
Capitol

Jim Hatfield wrote in message ...


They have these things called wirenuts which are the recommended
way of joining the wire. Sort of like a plastic cone containing
a cone-shaped brass fitting with an internal thread. You twist the
wire ends together and screw the wirenut onto the ends.


This is normally followed by the fire, with double the current being
required per KW, overheating is common!

Regards
Capitol

Owain pretended :
Scruit(tm)

Ta!

--


--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.org

In article om,
"Dave Liquorice" writes:
On Thu, 11 Mar 2004 16:12:56 +0000, Parish wrote:

Think about how you would achieve (110 - 0v - 110v) centre tapping
at the mid point of each phase.... :-)

Thats what a center tapped transformer does...

You mean you would need 6 cables rather than 3 for distribution?

Nope. The US distribution is 3 wire (phase).

It's usually just single phase per street, at something like 4500V
or 13000V (can't remember exact figures). This is dropped to 120-0-120
in pole mounted dustbin sized oil filled transformers (rather imfamous
for overheating and blowing up) each of which feeds a few houses.

The normal US domestic
supply is really a 230v center tapped one.

That's misleading. Regulation is at the 120V level, not just across
the two 240V hots.

Heavy loads like the aircon
etc are connected across the full windings and the ordinary 115v stuff

US is 120V actually, with some States having reduced that to 117V
to reduce energy consumption.

across half the winding. Donno where earth fits into the scheme of
things the yanks tend not to use it as their system is "balanced".

The 0V centre tap is earthed, and more recent installations include
earth runs in the wiring. However, earthed socket outlets with no
earth connected are not uncommon (and are even allowed if you have
an RCD in the circuit).

The big snag with 115v is that you need double the current for the
same power. So your 3kW kettle draws 26A instead of 13, voltage
fluctuations as loads change are much bigger problem in the US than
over here simply due to ohms law.

Also, they mix power and lighting on the same branch circuit, which
does nothing to help this situation.

--
Andrew Gabriel

In article ,
Andy Hall writes:

It's different connector types completely for 220v.

There are lots of different ones -- they don't have a single standard
for 240V outlets.

The consumer
units tend to be pretty big with a lot of breakers because there are
lots of radial circuits.

IIRC, 115v circuits are wired with black/white/green and 220v with two
blacks and a green.

240V circuits are red/black/white/green with red and black being the
two hots. They usually carry the 0V line too as many 240V appliances
also require 120V for things like integral lights, small motors,
timeswitches, etc. I believe 240V circuits are allowed (or were at
one time) to combine the 0V and protective earth in a single circuit
conductor.

In premises wiring, the earth is normally just bare. The NEC (US
wiring regs) actually allows green/yellow earth too, but I've never
seen it used in the US.

BTW, am I correct in thinking that, in our system, the Live should more
correctly be called Line?

That term is sometimes used.

'Phase' is another.

--
Andrew Gabriel

In article k,
Alistair Riddell writes:
On Thu, 11 Mar 2004, Harry Bloomfield wrote:

...and I think I read something about it now being legal to use 240v on
sites, providing an RCD was fitted.

It is permitted according to newer versions of the regs (BS7671), though I
am not clear whether both are permitted at the same time.

EU forced it on the UK -- EU wanted to outlaw the UK 110V supply.
The compromise was that we removed the restriction that appliances
on construction sites under 4kW had to run on no more than 60V
above earth. Whilst it might not be illegal to find 230V supply on
a construction site any more, in practice you still won't.

--
Andrew Gabriel

Andrew Gabriel wrote:
However, earthed socket outlets with no
earth connected are not uncommon (and are even allowed if you have
an RCD in the circuit).


Is that not bloody dangerous? An appliance that needs earthing plugged
into a socket with no earth connection?

"Andrew Gabriel" wrote in message
...
In article ,
Andy Hall writes:

It's different connector types completely for 220v.

There are lots of different ones -- they don't have a single standard
for 240V outlets.

The consumer
units tend to be pretty big with a lot of breakers because there are
lots of radial circuits.

IIRC, 115v circuits are wired with black/white/green and 220v with two
blacks and a green.

240V circuits are red/black/white/green with red and black being the
two hots. They usually carry the 0V line too as many 240V appliances
also require 120V for things like integral lights, small motors,
timeswitches, etc. I believe 240V circuits are allowed (or were at
one time) to combine the 0V and protective earth in a single circuit
conductor.

In premises wiring, the earth is normally just bare. The NEC (US
wiring regs) actually allows green/yellow earth too, but I've never
seen it used in the US.

BTW, am I correct in thinking that, in our system, the Live should more
correctly be called Line?

That term is sometimes used.

'Phase' is another.


All in all, it's a bit of a dog's breakfast really, innit?



--
Richard Sampson

email me at
richard at olifant d-ot co do-t uk

On Fri, 12 Mar 2004 16:36:11 -0000, "RichardS" noaccess@invalid
wrote:



All in all, it's a bit of a dog's breakfast really, innit?

Definitely. Try taking a look at American wiring accessories and
techniques. It makes the crappiest stuff here look like quality.



..andy

To email, substitute .nospam with .gl

Andy Hall writes:
On Fri, 12 Mar 2004 16:36:11 -0000, "RichardS" noaccess@invalid
wrote:



All in all, it's a bit of a dog's breakfast really, innit?

Definitely. Try taking a look at American wiring accessories and
techniques. It makes the crappiest stuff here look like quality.

We went into a hardware store in Manhattan Beach (Los Angeles) to buy
a plug for something, once. I was horrified at the "quality" of the
electrical fittings.


--
"The road to Paradise is through Intercourse."
[email me at huge [at] huge [dot] org [dot] uk]

Huge wrote:
We went into a hardware store in Manhattan Beach (Los Angeles) to buy
a plug for something, once. I was horrified at the "quality" of the
electrical fittings.

....and extension leads look like bell wire.

--
Toby.

'One day son, all this will be finished'

In article ,
Parish writes:
Andrew Gabriel wrote:
However, earthed socket outlets with no
earth connected are not uncommon (and are even allowed if you have
an RCD in the circuit).


Is that not bloody dangerous? An appliance that needs earthing plugged
into a socket with no earth connection?

We would think so. They apparently do not.

--
Andrew Gabriel

In article ,
"Toby" writes:
Huge wrote:
We went into a hardware store in Manhattan Beach (Los Angeles) to buy
a plug for something, once. I was horrified at the "quality" of the
electrical fittings.

...and extension leads look like bell wire.

Unless you want to run anything slightly meaty over more than
a few feet, in which case you could almost mistake them for
the hose pipe...

--
Andrew Gabriel

Parish wrote in message ...
Andrew Gabriel wrote:
However, earthed socket outlets with no
earth connected are not uncommon (and are even allowed if you have
an RCD in the circuit).


Is that not bloody dangerous? An appliance that needs earthing plugged
into a socket with no earth connection?

The American GFCIs are mounted in the socket and are very sensitive,
unlike ours, so as long as it does trip it is quite safe to use earth
requiring goods with no earth. The problem is that GFCIs do have a
failure mode or two, and therein lies the risk. Their systems is safe
as long as it works, whereas ours is more inherently safe. America has
more electrical accidents per person than us.


Regards, NT

(Andrew Gabriel) wrote in message ...
In article ,
Andy Hall writes:

240V circuits are red/black/white/green with red and black being the
two hots. They usually carry the 0V line too as many 240V appliances
also require 120V for things like integral lights, small motors,
timeswitches, etc. I believe 240V circuits are allowed (or were at
one time) to combine the 0V and protective earth in a single circuit
conductor.

Earth wires normally connect to the neutral supply wire at the CU. I
forget the details but basically they dont seem to worry about keeping
earth and neutral separate like we do.

There are lots of apartments that still have their 1930s wiring, with
no earth anywhere on the premises, with very inadequate capacity,
typically 30A at 110v for the whole flat, and in god knows what
condition. Seems to be one of the more common complaints about
renting.

Their CU breakers are thermal only, no magnetic component, so they
behave more like fuses than our MCBs.

Their table lamps usually use cardboard for insulation in the hot
bulbholder, and figure of 8 speaker wire for mains leads.

If the neutral wire comes adrift at the CU then the voltages vary
wildly, popping any appliances in sight. You just get 2 sets of 110v
appliances in series then.

The trouble in America is basically that they have so many very poor
inhabitants, that enforcing higher standards would be hopelessly
difficult. Another factor is the prevailing political beliefs, whch
basically boil down to: we must always let the market decide, and not
interfere with that hallowed process.


In premises wiring, the earth is normally just bare. The NEC (US
wiring regs) actually allows green/yellow earth too, but I've never
seen it used in the US.

I have never seen any sense in insulating our earth wires - I'm with
them on that one.


Regards, NT

In article , Harry
Bloomfield writes
Owain presented the following explanation :
The 110V is actually 55-0-55V centre tapped, so the maximum shock voltage to
earth is 55V. That's a lot safer than 240V. The idea predates the
widespread use of RCDs.

...and I think I read something about it now being legal to use 240v on
sites, providing an RCD was fitted.


110V filament bulbs will be a bit more robust too, because they'll have
thicker filaments.

Someone else though claimed it was an anti-theft "feature"[1] - less
attractive to nick for flogging down the pub. He was adamant about
this as he "has a mate in the trade who told him".

There is that as well. I think either London or New York underground railway
used backwards-threaded lightbulbs to discourage theft.

Certain hospitals used to use a round pin 13amp plug of their own
design, where one of the pins was a fuse, as a theft prevention measure.

And we used t have 3-peg bayonet fittings. I've only ever seen them in
enlarger lamp fittings, but I suspect that the original use was theft
prevention.



Regards,

Simonm.

--
simonm|at|muircom|dot|demon|.|c|oh|dot|u|kay
SIMON MUIR, UK INDEPENDENCE PARTY, BRISTOL www.ukip.org
EUROPEANS AGAINST THE EU www.members.aol.com/eurofaq
GT250A'76 R80/RT'86 110CSW TD'88 www.kc3ltd.co.uk/profile/eurofollie/

In article , Rod Hewitt
writes
Harry Bloomfield wrote in
o.uk:

Harry Bloomfield laid this down on his screen :
Parish wrote on 11/03/2004 :
That rings a bell, but wouldn't that be for having separate circuits
for critical equipment, such as Life Support Machines, so only such
items could be plugged into them? Stop Mrs. Mopp unplugging a LSM to
use the floor polisher :-)

That might be the reason why they are still used (I could not
comment, I have not been involved with that side of hospitals for a
long time), but I am talking about lots of years ago when plug tops
were considered to be expensive items. The hospital had these fitted
to all of their protable equipment throughout. From memory, they
looked very similar to a 5amp plug, but the the live pin could be
unscrewed and formed the fuse.

The ones I have seen are almost identical to standard 13 amp plugs but with
all pins rotated 90 degrees. Typically used in theatres (operating) and
intensive/special care units.

Walsall "B" gauge. The 5A round-pin plugs mentioned above were somewhat
earlier, but still urn up occasionally at car boots, etc. I bet someone
still makes the fuses, somewhere, as India is still round-pin, and all
the 5A stuff I bought for lighting recently came from there.


Regards,

Simonm.

--
simonm|at|muircom|dot|demon|.|c|oh|dot|u|kay
SIMON MUIR, UK INDEPENDENCE PARTY, BRISTOL www.ukip.org
EUROPEANS AGAINST THE EU www.members.aol.com/eurofaq
GT250A'76 R80/RT'86 110CSW TD'88 www.kc3ltd.co.uk/profile/eurofollie/

In article ,
SpamTrapSeeSig wrote:
Walsall "B" gauge. The 5A round-pin plugs mentioned above were somewhat
earlier, but still urn up occasionally at car boots, etc. I bet someone
still makes the fuses, somewhere, as India is still round-pin, and all
the 5A stuff I bought for lighting recently came from there.

The D&S plugs with screw in fuses may look vaguely like a 5 amp, but are
13 amp designed to be used on a ring main.

--
*If a pig loses its voice, is it disgruntled?

Dave Plowman London SW 12
RIP Acorn

SpamTrapSeeSig wrote in
:

And we used t have 3-peg bayonet fittings. I've only ever seen them in
enlarger lamp fittings, but I suspect that the original use was theft
prevention.

And railway carriage lighting (at least on Southern Region EMUs).
--
Rod

www.annalaurie.co.uk

Jim Michaels wrote in message ...


They have these things called wirenuts which are the recommended
way of joining the wire. Sort of like a plastic cone containing
a cone-shaped brass fitting with an internal thread. You twist the
wire ends together and screw the wirenut onto the ends.


This is normally followed by the fire, with double the current being
required per KW, overheating is common!

Regards
Capitol


Not common, actually very rare and only when mis-installed.


Sufficiently common that it is now proposed to fit Arc Fault Circuit
Interrupter devices to each spur and it is suggested that this will reduce
the number of fires caused by electrical wiring by 50%. 326 deaths, 1481
injuries and $646M in property cost losses over a 9 year period!

Regards
Capitol

Capitol wrote in message ...

Jim Michaels wrote in message ...


They have these things called wirenuts which are the recommended
way of joining the wire. Sort of like a plastic cone containing
a cone-shaped brass fitting with an internal thread. You twist the
wire ends together and screw the wirenut onto the ends.


This is normally followed by the fire, with double the current being
required per KW, overheating is common!

Regards
Capitol


Not common, actually very rare and only when mis-installed.


Sufficiently common that it is now proposed to fit Arc Fault Circuit
Interrupter devices to each spur and it is suggested that this will reduce
the number of fires caused by electrical wiring by 50%. 326 deaths, 1481
injuries and $646M in property cost losses over a 9 year period!

Sorry, missed some info. 38.4K electrical distribution fires per year on
average in US.

Regards
Capitol

In article ,
Jim Michaels wrote:
Use Google and search for wire nut fire.

They probably as dangerous as Choc blocks..

Given that every wiring accessory uses a connection method identical to a
choccy block, why should a correctly specified and protected one be any
different?

--
*A hangover is the wrath of grapes.

Dave Plowman London SW 12
RIP Acorn

"Dave Plowman" wrote in message
...
In article ,
Jim Michaels wrote:
Use Google and search for wire nut fire.

They probably as dangerous as Choc blocks..

Given that every wiring accessory uses a connection method identical to a
choccy block, why should a correctly specified and protected one be any
different?


Because some busy-body, who probably doesn't have enough real work to do has
decided that they are ?.....

Jim Michaels wrote in message
Electrical sources accounted for 58% of the 55,000 reported fire
incidents in the UK over the years 1994-1998

http://www.cefic-efra.org/pdf/1202/EFRA_TV_fire.pdf

http://www.interfire.org/features/el...ing_faults.asp

http://www.odpm.gov.uk/stellent/grou...ge/odpm_fire_6
00678-01.hcsp

http://www.cpsc.gov/library/fire99.pdf


I suggest you try checking the number of fires attributed to household
wiring installations in the UK, they are very few! Chocolate blocks are a
far superior electrical connection to wire nuts. I've never found a reliable
piece of military or aviation equipment which uses wirenuts (wirewrap-yes)
and I've seen plenty which use chocolate block type connections.

Wirenuts are a fire waiting to happen IMO and frequently it does ( in spite
of the very good UL wire specifications)!

Regards
Capitol