Roger Hayter wrote:
How has it come about that electricity plugs are called "plug tops" and
electricity sockets are called "plug sockets"? There seems to be no ambiguity
using just "plugs" and "sockets".

Plug top v plug bottom :-)

Theo

On 10/04/2021 13:02, Roger Hayter wrote:
On 10 Apr 2021 at 11:32:56 BST, "Theo"
wrote:

Max Demian wrote:
I would have thought it would be better to have fused sockets, then
there wouldn't be the chance of overload with multiple appliances
plugged into the socket with an unfused adapter.

The circuit breaker (or rewireable fuse) is supposed to protect the house
wiring. The plugtop fuse is to protect the appliance wiring. A fused
socket can't tell whether you plugged in a 1A appliance or a 13A appliance.
If the 1A appliance starts taking 10A its cable may melt, but a 13A fused
socket wouldn't notice. By putting a 1A fuse in the plugtop you can protect
the appliance's cable.

If you're running a multiway extension then that has a fuse in /its/ plugtop
which is matched to the maximum current the extension can handle. If you
daisy chain extensions, or plug in three kettles, that fuse should blow
before troubling the circuit breaker. There shouldn't be unfused adapters,
because then you're only relying on the circuit breaker.

If you have a removable appliance cable, like a C13 'kettle lead', the same
holds if the fuse in the plugtop is rated for the size of the cable - it's
fine to fit a 10A fuse on a C13 cable capable of carrying 10A - as long as
the appliance has its own fuse (typically at the IEC inlet) rated for its
own requirements.

Theo

How has it come about that electricity plugs are called "plug tops" and
electricity sockets are called "plug sockets"? There seems to be no ambiguity
using just "plugs" and "sockets".


the story I recall is that it dates from the early days when electrical
connections one could make and break were novel and were sold as plug
points, each of which comprised the bit you pushed in (the plug top) and
the bit you pushed it into (the plug socket). And I think this was
before the days of sockets on domestic walls.

--
Robin
reply-to address is (intended to be) valid

In article ,
charles wrote:
In article , Dave Plowman (News)
wrote:
In article , SH
wrote:
They are bigger. Still used in theatres. ^^^



The reason for that is if a plug had a fuse in it and it blew during a
live performance, it was not a quick or safe job to get a maintenance
man out to climb into the suspended walkways in the dark, find the
plug, unplug it, take it apart, replace fuse, reassemble the plug,
plug it back in and vacate the suspended walkways.

Err, theatre lighting doesn't use a ring main. Most usually a radial
with dimmer control. You don't want such circuits confused with a GP
mains supply - hence different connectors.

yes, but the reason is you don't want a fuse in some remote part of the
rig.

Chicken and egg? I'm willing to bet there are some projection/effect
luminaires that do have a local fuse somewhere, though.

--
*Marriage changes passion - suddenly you're in bed with a relative*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Roger Hayter wrote:
How has it come about that electricity plugs are called "plug tops" and
electricity sockets are called "plug sockets"? There seems to be no ambiguity
using just "plugs" and "sockets".

Sadly, many call the sockets plugs. As in that room has plenty plugs. Plug
top at least differentiates from that.

--
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Dave Plowman London SW
To e-mail, change noise into sound.

On Sat, 10 Apr 2021 19:59:27 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


FLUSH the trolling senile asshole's latest troll**** unread

--
Bod addressing senile Rot:
"Rod, you have a sick twisted mind. I suggest you stop your mindless
and totally irresponsible talk. Your mouth could get you into a lot of
trouble."
Message-ID:

On 10/04/2021 11:21, Max Demian wrote:
On 10/04/2021 10:24, Owain Lastname wrote:
On Saturday, 10 April 2021 at 01:26:43 UTC+1, Rod Speed wrote:
There were lots of small appliances intended for use on 2A
and 5A plugs, with thin flexes.
Doesnt explain why all other countrys
handle those fine without fused plug tops.

1. Because they didn't have 2A and 5A circuits, their appliances had
thicker flexes?
2. Many European countries had bottle fuses which may have provided
finer protection than rewireable fuses used in Britain.
3. Their electrical safety standards were/are lower?
4. We designed the fused 13A plug to suit the conditions in the UK at
the time and to be the best possible solution overall, albeit a
compromise in some ways.

I would have thought it would be better to have fused sockets, then
there wouldn't be the chance of overload with multiple appliances
plugged into the socket with an unfused adapter.

But then they'd all have 13A fuses. Fusing the plugs allows for
different fuses to suit different appliance requirements and flex ratings.

I could have a flex suitable for a 13A fuse on my 17W soldering iron (it
actually has a 3A fuse), but the thicker, heavier, less flexible wiring
required would make using it far more difficult.

Such cables may also pull table lamps and other light items out of position.

On 10/04/2021 12:06, Dave Plowman (News) wrote:
In article ,
Max Demian wrote:

I would have thought it would be better to have fused sockets, then
there wouldn't be the chance of overload with multiple appliances
plugged into the socket with an unfused adapter.

How would the socket know which fuse to fit? Never noticed some appliances
come with a 5 amp fuse in the plug?

Fuses mostly only protect against a dead short. To protect the
appliance, e.g. a PSU, you need a fuse on the output or a thermal cutout.

--
Max Demian

On 10/04/2021 17:57, Max Demian wrote:
On 10/04/2021 12:06, Dave Plowman (News) wrote:
In article ,
Â*Â*Â* Max Demian wrote:

I would have thought it would be better to have fused sockets, then
there wouldn't be the chance of overload with multiple appliances
plugged into the socket with an unfused adapter.

How would the socket know which fuse to fit? Never noticed some
appliances
come with a 5 amp fuse in the plug?

Fuses mostly only protect against a dead short. To protect the
appliance, e.g. a PSU, you need a fuse on the output or a thermal cutout.

The theory is that the MCB protects the house wiring, and the plug fuse
protects the wire to the appliance, after that, its likely there will be
an internal fuse to protect the magic smoke generators


--
All political activity makes complete sense once the proposition that
all government is basically a self-legalising protection racket, is
fully understood.

"Max Demian" wrote in message
...
On 10/04/2021 10:24, Owain Lastname wrote:
On Saturday, 10 April 2021 at 01:26:43 UTC+1, Rod Speed wrote:
There were lots of small appliances intended for use on 2A
and 5A plugs, with thin flexes.
Doesnt explain why all other countrys
handle those fine without fused plug tops.

1. Because they didn't have 2A and 5A circuits, their appliances had
thicker flexes?
2. Many European countries had bottle fuses which may have provided finer
protection than rewireable fuses used in Britain.
3. Their electrical safety standards were/are lower?
4. We designed the fused 13A plug to suit the conditions in the UK at the
time and to be the best possible solution overall, albeit a compromise in
some ways.

I would have thought it would be better to have fused sockets, then there
wouldn't be the chance of overload with multiple appliances plugged into
the socket with an unfused adapter.

Real bugger to change the fuse when its down on the skirting board tho
and impossible to make doing that safe for the technostupids. Easy on
both counts when the fuse is in the plug.

Well, All I can tell you is that people moved in in 1942 according though
the searches. The sockets were made of a very brittle brown bakelite
substance and we had to change them in 1956 when we moved in as some had
clearly overheated due to loose screw syndrome. I did go into several of the
houses along this terrace back around 58 or so and remember, being a nerd
back then too, that they all had 13 amp square shuttered pin sockets, so
unless somebody did the whole block at once, then they must have been here
since just before the war.
I guess its possible that some damage was done during the war needing some
work to them all, but no mention on the search. I was still a child but
loved things electrical back then as well.


I'm not going to do loads of research on tit but there were a couple of
socket adaptors left here when we moved in, one was for a large round pin
socket the others were several small three pin sockets on a box shaped 13a
adaptor. None of these adaptors were fused and of cours no plug back then
had shrouded pins and some of the sockets shutters were jammed open, one
assumes to poke wires in with the usual lethal consequences no doubt.
Another device that was left in the cupboard under the stairs was an
electric iron terminated in a bayonet plug that went into a light fitting.
of Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Dave Plowman (News)" wrote in message
...
In article ,
Brian Gaff \(Sofa\) wrote:
Might I just say that although this house was built in 1939, it was
built using 13 amp sockets on the old rubber and fabric covered wires,
including earth.

Pretty certain 13 amp was a post war thing, Brian. But it could have taken
a long time to build your house. ;-)

--
*A plateau is a high form of flattery*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Brian Gaff \(Sofa\) wrote:
Well, All I can tell you is that people moved in in 1942 according
though the searches. The sockets were made of a very brittle brown
bakelite substance and we had to change them in 1956 when we moved in as
some had clearly overheated due to loose screw syndrome. I did go into
several of the houses along this terrace back around 58 or so and
remember, being a nerd back then too, that they all had 13 amp square
shuttered pin sockets, so unless somebody did the whole block at once,
then they must have been here since just before the war. I guess its
possible that some damage was done during the war needing some work to
them all, but no mention on the search. I was still a child but loved
things electrical back then as well.


I'm not going to do loads of research on tit but there were a couple of
socket adaptors left here when we moved in, one was for a large round
pin socket the others were several small three pin sockets on a box
shaped 13a adaptor. None of these adaptors were fused and of cours no
plug back then had shrouded pins and some of the sockets shutters were
jammed open, one assumes to poke wires in with the usual lethal
consequences no doubt. Another device that was left in the cupboard
under the stairs was an electric iron terminated in a bayonet plug that
went into a light fitting. of Brian

According to Wiki, a committee was convened in 1942 to look into the ring
main idea. But no information when production of the sockets and plugs
actually started. My guess is factories would be busy with other things
until near the end of the war.

--
*Your kid may be an honours student, but you're still an idiot.

Dave Plowman London SW
To e-mail, change noise into sound.

On 11/04/2021 09:50, Brian Gaff (Sofa) wrote:
Well, All I can tell you is that people moved in in 1942 according though
the searches. The sockets were made of a very brittle brown bakelite
substance and we had to change them in 1956 when we moved in as some had
clearly overheated due to loose screw syndrome. I did go into several of the
houses along this terrace back around 58 or so and remember, being a nerd
back then too, that they all had 13 amp square shuttered pin sockets, so
unless somebody did the whole block at once, then they must have been here
since just before the war.

The BS1363 13A plug and socket were not introduced until 1947.