On Jan 5, 9:51*pm, Terry Casey wrote:
In article ,
says...











On 04/01/2012 17:50, Ian wrote:

2pin 3A
3pin 3A
3pin 5A
3pin 15A
3pin (round pin, fused pin) 13A
Clock outlet.

I may have left one or two out.

ISTR 3 different sizes of 2 pin plugs in the early 1950's. They had pin
sizes similar to current 2A, 5A and 15A round pin plugs but I think the
larger ones might have been known as 10A - no one had anything more
powerful than a 2 bar electric fire in those days.

What was a pain, and for which I can see no logical reason,[1] is that
the live pin spacing differed between 2-pin and 3-pin versions. This
meant that if you had a device which didn't require an earth and was
fitted with, say, a 5A 2P plug, you couldn't plug it in to a 5A 3P
socket, which was rather stupid as it would have been perfectly safe.

I remember 5A adapters that had a 3P socket at the front and two 2P
sockets on the sides.

MBQ

On Jan 5, 4:01*pm, John Rumm wrote:
On 05/01/2012 13:08, Man at B&Q wrote:

On Jan 4, 11:27 pm, Andy *wrote:
On 04/01/2012 16:36, John Rumm wrote:

That's 237 kWh of electricity...

27 quid.

Makes you wonder what the testing labs lekky bill would be like after
doing a few of those ;-)

Hardly likely to be a concern - anyway the current/heating tests can be
done at arbitrarily low voltage. *It's only I^2*R ...

Which is power. The same regardless of the voltage you use. If R is
fixed, reducing V will reduce I.

That would be a woosh then ;-)

Yes :-(

MBQ

On Jan 5, 2:46*pm, John Rumm wrote:
On 05/01/2012 13:08, Man at B&Q wrote:









On Jan 5, 10:20 am, John *wrote:
On 04/01/2012 23:27, Andy Wade wrote:

On 04/01/2012 16:36, John Rumm wrote:

That's 237 kWh of electricity...

27 quid.

Makes you wonder what the testing labs lekky bill would be like after
doing a few of those ;-)

Hardly likely to be a concern - anyway the current/heating tests can be
done at arbitrarily low voltage. It's only I^2*R ...

Yes good point, the BS does not actually specify the test voltage for
those particular tests.

Another one I thought had more intelligence.

Huh?

I was being woooshed.

MBQ

On Thu, 5 Jan 2012 23:32:03 +0000 Mike Clarke wrote :
Yes, I remember us having some 2 way adaptors which had cunning
overlapping holes to allow either a 2 pin or 3 pin 5A plug to be used.
They must have had rather weird contacts inside.

I remember a device called a Flexiplug - as you moved a shutter different
pins dropped out which you unscrewed to lock them in place so it could act
as 2 or 3 pin 2A, 5A or 15A plug - it must have had a 13A option too.

--
Tony Bryer, Greentram: 'Software to build on',
Melbourne, Australia www.greentram.com

On Fri, 06 Jan 2012 22:59:38 +1100
Tony Bryer wrote:

I remember a device called a Flexiplug - as you moved a shutter
different pins dropped out which you unscrewed to lock them in place
so it could act as 2 or 3 pin 2A, 5A or 15A plug - it must have had a
13A option too.

Yup, I've got a "Fitall Plug" in the "Bits I haven't used for years but
might need sometime" box. It does 13A, 15A and 5A but only 3 pin. Move
a lever to let the desired pins slide out and twist them to lock.

It was quite fiddly to set up but useful to have on a short lead
with a 13A socket on the other end so I could use my stuff when
visiting places which still had old style sockets. And, no, I didn't
try to use it to power a 3KW heater from a 5A socket.

--
Mike Clarke

Lieutenant Scott wrote:
On Thu, 05 Jan 2012 13:04:03 -0000, ARWadsworth
wrote:
dennis@home wrote:
"Lieutenant Scott" wrote in message
newsp.v7lx6ngiytk5n5@i7-940...

There's plenty 3kW appliances, which is 12A.

You won't win, doing the job properly costs too much (about £1).
Its the users fault anyway for using both the sockets.
Just hope its not an old spur with 22A cable feeding it with the
cable behind dry lined PB on thermal blocks with PVC capping.

Imagine what could happen if a retard was let loose with an
induction hob.

Less than a normal hob.

Indeed. And you are probably unaware that your hero dennis managed to start
a fire using an induction hob. His first attempt failed as he did not
realise his non magnetic pans would not work on the hob.

However, the fool went and bought a cheap iron wok to try and managed to set
the thing on fire.

--
Adam

"John Rumm" wrote in message
...

Try and comprehend, this has nothing to do with the user, and everything
to do with the designer and installer. If the designer does their job
right, the user can get on and use a system that is flexible, does what
they need, does not give spurious trips. and remains safe.

Try and comprehend that the designer is putting in a system that will be in
place for decades.
The users will die (hopefully not from design faults), other users will
arrive, the designer has no idea what they will do in 5 years time let alone
50.
All of your so called good design ideas have problems that get worse with
time, you know minor things like undetectable faults developing.
Any engineer would recognise these problems and avoid them where possible,
not just follow some *minimum* standard that needs revising. No, sorry, I
meant has been revised several times due to the minimums it set being too
minimum to be safe.
You can assume the current (pun intended) minimums are OK but I expect them
to be revised in my direction not to stay where you think they should be,


You might like to mandate that a 32A circuit is dedicated to each and
every double socket, but fortunately its not your decision, and no one
else thinks its a good idea. So you may as well learn to live with it.

As a designer one has the freedom to make sensible choices about matching
the installation to the pattern of use. This is a system that works
remarkably well in practice, and has given the UK the safest electrical
systems in the world.

If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning about it
here.

You moan about it, I just don't do minimums to save a few pence.

Some idiot answering to "ARWadsworth" wrote
in message ...

Indeed. And you are probably unaware that your hero dennis managed to
start a fire using an induction hob. His first attempt failed as he did
not realise his non magnetic pans would not work on the hob.

The idiot ARW doesn't understand that there are pans made of stainless that
do work on induction hobs and the easy way to find out is try one.


However, the fool went and bought a cheap iron wok to try and managed to
set the thing on fire.

Well yes but it was steel not iron and it was a warning about how fast the
thin ones heat up, like about 5 seconds and a teaspoon of oil doesn't make
much of a fire.
However I now have some new pans with a thicker bas and they work fine

ARW being a childish bully type thinks it makes a difference to me when he
keeps posting his cr@p.
The reality of course is it makes him look like the idiot he is.

It really upsets him that I read his cr@p and treat him with contempt and
ignore him.

On Jan 6, 8:58 pm, "dennis@home"
wrote:

It really upsets him that I read his cr@p and treat him with contempt and
ignore him.

erm.... run that last bit by me again.??....

(PS nearly 1/2 way tgo breaking Google Groups again - woo hoo ;)))

Jim K

On Fri, 6 Jan 2012 12:57:31 +0000 Mike Clarke wrote :
Yup, I've got a "Fitall Plug" in the "Bits I haven't used for years but
might need sometime" box. It does 13A, 15A and 5A but only 3 pin. Move
a lever to let the desired pins slide out and twist them to lock.

That sounds like the one I remember. It's good to live in an age where
such things are no longer needed!

--
Tony Bryer, Greentram: 'Software to build on',
Melbourne, Australia www.greentram.com

"Jim K" wrote in message
...
On Jan 6, 8:58 pm, "dennis@home"
wrote:

It really upsets him that I read his cr@p and treat him with contempt and
ignore him.

erm.... run that last bit by me again.??....

(PS nearly 1/2 way tgo breaking Google Groups again - woo hoo ;)))

(I can help there.)

Jim K

On Jan 6, 9:28 pm, "dennis@home"
wrote:
"Jim K" wrote in message

...

On Jan 6, 8:58 pm, "dennis@home"
wrote:

It really upsets him that I read his cr@p and treat him with contempt and
ignore him.

erm.... run that last bit by me again.??....

(PS nearly 1/2 way tgo breaking Google Groups again - woo hoo ;)))

(I can help there.)

& don't it feel good ?

Jim K

"Jim K" wrote in message
...
On Jan 6, 9:28 pm, "dennis@home"
wrote:
"Jim K" wrote in message

...

On Jan 6, 8:58 pm, "dennis@home"
wrote:

It really upsets him that I read his cr@p and treat him with contempt
and
ignore him.

erm.... run that last bit by me again.??....

(PS nearly 1/2 way tgo breaking Google Groups again - woo hoo ;)))

(I can help there.)

& don't it feel good ?

Anything that breaks Google is good.

Maybe we should just choose a long thread and change its title instead of
starting new threads?

On Jan 6, 9:44 pm, "dennis@home"
wrote:
"Jim K" wrote in message

...



On Jan 6, 9:28 pm, "dennis@home"
wrote:
"Jim K" wrote in message

...

On Jan 6, 8:58 pm, "dennis@home"
wrote:

It really upsets him that I read his cr@p and treat him with contempt
and
ignore him.

erm.... run that last bit by me again.??....

(PS nearly 1/2 way tgo breaking Google Groups again - woo hoo ;)))

(I can help there.)

& don't it feel good ?

Anything that breaks Google is good.

Maybe we should just choose a long thread and change its title instead of
starting new threads?

why don't you just resolve to only answer your own posts from now on
and then you can claim all the credit for yourself?

Jim K

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:

On 05/01/2012 20:17, dennis@home wrote:


"John Rumm" wrote in message
o.uk...
On 05/01/2012 11:20, dennis@home wrote:


"Lieutenant Scott" wrote in message
newsp.v7lx6ngiytk5n5@i7-940...

There's plenty 3kW appliances, which is 12A.

You won't win, doing the job properly costs too much (about £1).

We are not all tightwads like you dennis...

Its the users fault anyway for using both the sockets.

Why?

Just hope its not an old spur with 22A cable feeding it with the cable
behind dry lined PB on thermal blocks with PVC capping.

You could do with getting a handle on this concept we call "design".
You make an assessment of the typical load, look at the installation
conditions, and then specify an appropriate installation.

What might be appropriate for a socket behind a TV is very different
for one in a utility room where you expect a washing machine and
tumble drier to be installed.

Here we are again.
If the user is stupid enough to use both sockets behind the TV to
maximum its their own fault and they deserve what they get.

Are you genuinely stupid dennis, or just being obtuse because you like
arguing?

Try and comprehend, this has nothing to do with the user, and everything
to do with the designer and installer. If the designer does their job
right, the user can get on and use a system that is flexible, does what
they need, does not give spurious trips. and remains safe.

Having a system which can overheat without tripping something is NOT
safe, is a BAD design, and should NOT be done by anyone who calls
themselves qualified.

Well unless you are talking about the current limit on the double socket
itself (which if you wish to avoid, you will need to use single
sockets), then we are actually in agreement.

You might like to mandate that a 32A circuit is dedicated to each and
every double socket, but fortunately its not your decision, and no one
else thinks its a good idea. So you may as well learn to live with it.

Where did you pull that one from? Nobody has mentioned seperate

This is a bit of historic dennis... don't worry about it.

circuits. As long as you can't overheat something. The max load
handleable by any one point in the circuit (in this case the double
socket) should be equal to or more than the protective fuse or breaker.

Not really a logical deduction is it. The circuit can feed far more than
one socket, so there is no point limiting its design current to
something that just one socket can handle.

As a designer one has the freedom to make sensible choices about
matching the installation to the pattern of use. This is a system that
works remarkably well in practice, and has given the UK the safest
electrical systems in the world.

Don't guess at patterns. Allow for what COULD happen. "Oh the user most
likely won't do this" is just not good enough.

Engineering decisions are frequently made on the balance of probabilities.

If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning about
it here.

Why can't he moan about people like you who agree with the incorrect 17th?

Well he can, but its pointless because we don't agree with him. If he
wants something to be different, then he would need to address his
concerns to the people able to change the requirements.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 06/01/2012 20:47, dennis@home wrote:


"John Rumm" wrote in message
...

Try and comprehend, this has nothing to do with the user, and
everything to do with the designer and installer. If the designer does
their job right, the user can get on and use a system that is
flexible, does what they need, does not give spurious trips. and
remains safe.

Try and comprehend that the designer is putting in a system that will be
in place for decades.

Indeed, not that it makes much difference...

If you start with the premise that with a new installation, all the
circuits are fundamentally sound. What needs to be addressed with the
design is making sure there is adequate provision of sockets etc, in the
places they are likely to be needed, and that the circuits selected are
appropriate.

That means where you put sockets, and how many you install will reflect
the anticipated use.

If there is only one logical place in a kitchen to stick a
fridge/freezer, then that would be a good place to stick the non RCD
protected socket with the "Freezer Only" label on it.

The users will die (hopefully not from design faults), other users will
arrive, the designer has no idea what they will do in 5 years time let
alone 50.

The kitchen will still be the kitchen, so the same basic provisions will
be required. If there is a 1200mm wide gap under a worktop, with two
sets of washing machine taps, two drainage stand pipes, and a tumble
drier vent, its still a pretty good guess that a couple of remotely
switched sockets under there are going to be equally handy in 30 years
as they are now.

Likewise 4 or 6 doubles in the corner of the lounge adjacent to the TV
aerial socket is also going to be a safe bet.

All of your so called good design ideas have problems that get worse
with time, you know minor things like undetectable faults developing.

Tis why I prefer to use more fault tolerant circuits in the first place.

Any engineer would recognise these problems and avoid them where
possible, not just follow some *minimum* standard that needs revising.
No, sorry, I meant has been revised several times due to the minimums it
set being too minimum to be safe.
You can assume the current (pun intended) minimums are OK but I expect
them to be revised in my direction not to stay where you think they
should be,


You might like to mandate that a 32A circuit is dedicated to each and
every double socket, but fortunately its not your decision, and no one
else thinks its a good idea. So you may as well learn to live with it.

As a designer one has the freedom to make sensible choices about
matching the installation to the pattern of use. This is a system that
works remarkably well in practice, and has given the UK the safest
electrical systems in the world.

If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning
about it here.

You moan about it, I just don't do minimums to save a few pence.

You mean install a couple of 20A radials where an electrician would
place a 32A ring circuit? Cost is about the same, but the ring circuit
will be less likely to cause the user problems with nuisance trips
because they plugged the wrong combination of appliances into a set of
sockets. The radials are also more likely to be subject to long term low
level overload - something that the designer is supposed to mitigate
against.

Use 4mm^2 cable instead of 2.5mm^2? Harder to wire, costs more, performs
the same. So why bother?

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article ,
says...

On Fri, 06 Jan 2012 22:59:38 +1100
Tony Bryer wrote:

I remember a device called a Flexiplug - as you moved a shutter
different pins dropped out which you unscrewed to lock them in place
so it could act as 2 or 3 pin 2A, 5A or 15A plug - it must have had a
13A option too.

Yup, I've got a "Fitall Plug" in the "Bits I haven't used for years but
might need sometime" box. It does 13A, 15A and 5A but only 3 pin. Move
a lever to let the desired pins slide out and twist them to lock.

It did 2 pin as well! There was a crack running through the base so that
you could change the pin pitch by squeezing it like nutcrackers.

It did have one drawback, though. The 5A live pin could get past the
fibre selector plate in the 13A position, which was not a problem until
you plugged it into a metal clad 13A socket!

It was interesting to go round a stage so equipped at any venue where
pop groups performed and look for the tell-tale crater on the face of
the sockets. At first, maybe only one, then two then, as the plugs
popularity rapidly increased, suddenly it was virtually impossible to
find a metal clad socket free of pock marks anywhere!

There was a MkII version which was modified to stop this happening but
it was a bit late in the day. I think most people had got in the habit
of putting a empty fag packet over the socket and forcing the plug
through it by then, anyway ...

It was quite fiddly to set up

Strange. I don't recall any problems!

--

Terry

"John Rumm" wrote in message
o.uk...
On 06/01/2012 20:47, dennis@home wrote:


"John Rumm" wrote in message
...

Try and comprehend, this has nothing to do with the user, and
everything to do with the designer and installer. If the designer does
their job right, the user can get on and use a system that is
flexible, does what they need, does not give spurious trips. and
remains safe.

Try and comprehend that the designer is putting in a system that will be
in place for decades.

Indeed, not that it makes much difference...

If you start with the premise that with a new installation, all the
circuits are fundamentally sound. What needs to be addressed with the
design is making sure there is adequate provision of sockets etc, in the
places they are likely to be needed, and that the circuits selected are
appropriate.

That means where you put sockets, and how many you install will reflect
the anticipated use.

If there is only one logical place in a kitchen to stick a fridge/freezer,
then that would be a good place to stick the non RCD protected socket with
the "Freezer Only" label on it.

The users will die (hopefully not from design faults), other users will
arrive, the designer has no idea what they will do in 5 years time let
alone 50.

The kitchen will still be the kitchen, so the same basic provisions will
be required. If there is a 1200mm wide gap under a worktop, with two sets
of washing machine taps, two drainage stand pipes, and a tumble drier
vent, its still a pretty good guess that a couple of remotely switched
sockets under there are going to be equally handy in 30 years as they are
now.

Likewise 4 or 6 doubles in the corner of the lounge adjacent to the TV
aerial socket is also going to be a safe bet.

All of your so called good design ideas have problems that get worse
with time, you know minor things like undetectable faults developing.

Tis why I prefer to use more fault tolerant circuits in the first place.

Any engineer would recognise these problems and avoid them where
possible, not just follow some *minimum* standard that needs revising.
No, sorry, I meant has been revised several times due to the minimums it
set being too minimum to be safe.
You can assume the current (pun intended) minimums are OK but I expect
them to be revised in my direction not to stay where you think they
should be,


You might like to mandate that a 32A circuit is dedicated to each and
every double socket, but fortunately its not your decision, and no one
else thinks its a good idea. So you may as well learn to live with it.

As a designer one has the freedom to make sensible choices about
matching the installation to the pattern of use. This is a system that
works remarkably well in practice, and has given the UK the safest
electrical systems in the world.

If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning
about it here.

You moan about it, I just don't do minimums to save a few pence.

You mean install a couple of 20A radials where an electrician would place
a 32A ring circuit? Cost is about the same, but the ring circuit will be
less likely to cause the user problems with nuisance trips because they
plugged the wrong combination of appliances into a set of sockets. The
radials are also more likely to be subject to long term low level
overload - something that the designer is supposed to mitigate against.

Use 4mm^2 cable instead of 2.5mm^2? Harder to wire, costs more, performs
the same. So why bother?

You still don't get it.. you want to work to the minimum standards, I don't.
You can do as you wish.
There is no need for the regs to change to make things better, all it takes
is a bit of thought.
I notice you don't mention putting a 20A breaker in the ring and getting all
the benefits of a ring and having less problems with faults.

dennis@home wrote:
Some idiot answering to "ARWadsworth"
wrote in message
...
Indeed. And you are probably unaware that your hero dennis managed to
start a fire using an induction hob. His first attempt failed as he
did not realise his non magnetic pans would not work on the hob.

The idiot ARW doesn't understand that there are pans made of
stainless that do work on induction hobs and the easy way to find out
is try one.

However, the fool went and bought a cheap iron wok to try and
managed to set the thing on fire.

Well yes but it was steel not iron and it was a warning about how
fast the thin ones heat up, like about 5 seconds and a teaspoon of
oil doesn't make much of a fire.
However I now have some new pans with a thicker bas and they work fine

I'm sure they do, considering that you sent the induction hob back to Aldi.

--
Adam

In message
, Jim
K writes
On Jan 6, 8:58 pm, "dennis@home"
wrote:

It really upsets him that I read his cr@p and treat him with contempt and
ignore him.

erm.... run that last bit by me again.??....


Oh do come on now, its his spell checker playing up again ...

--
geoff

On Fri, 06 Jan 2012 20:58:41 +0000, dennis@home wrote:
It really upsets him that I read his cr@p and treat him with contempt
and ignore him.

Do you have adults looking over your shoulder or something, and so you're
not allowed to type crap?

Jules Richardson wrote:
On Fri, 06 Jan 2012 20:58:41 +0000, dennis@home wrote:
It really upsets him that I read his cr@p and treat him with contempt
and ignore him.

Do you have adults looking over your shoulder or something, and so
you're not allowed to type crap?

He usually does:-)
--
Adam

"ARWadsworth" wrote in message
...
Robin wrote:
What a **** hole.

That seems to me rather harsh - especially as there's a bar of Lindt
with sea salt on offer. And the floor doesn't look bad to me for a
kitchen which has been used rather than prepared for a show home. But
then perhaps my standards are as low as my expectations.


My kitchen worktop usually has a cat asleep on it!

Paws for thought

On Fri, 06 Jan 2012 16:20:54 -0000, ARWadsworth wrote:

Lieutenant Scott wrote:
On Thu, 05 Jan 2012 13:04:03 -0000, ARWadsworth
wrote:
dennis@home wrote:
"Lieutenant Scott" wrote in message
newsp.v7lx6ngiytk5n5@i7-940...

There's plenty 3kW appliances, which is 12A.

You won't win, doing the job properly costs too much (about £1).
Its the users fault anyway for using both the sockets.
Just hope its not an old spur with 22A cable feeding it with the
cable behind dry lined PB on thermal blocks with PVC capping.

Imagine what could happen if a retard was let loose with an
induction hob.

Less than a normal hob.

Indeed. And you are probably unaware that your hero dennis managed to start
a fire using an induction hob. His first attempt failed as he did not
realise his non magnetic pans would not work on the hob.

However, the fool went and bought a cheap iron wok to try and managed to set
the thing on fire.

How is this possible?

--
http://petersparrots.com
http://petersphotos.com

The light at the end of the tunnel is the headlamp of the oncoming train..

On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:

On 05/01/2012 20:17, dennis@home wrote:


"John Rumm" wrote in message
o.uk...
On 05/01/2012 11:20, dennis@home wrote:


We are not all tightwads like you dennis...



Why?



You could do with getting a handle on this concept we call "design".
You make an assessment of the typical load, look at the installation
conditions, and then specify an appropriate installation.

What might be appropriate for a socket behind a TV is very different
for one in a utility room where you expect a washing machine and
tumble drier to be installed.

Here we are again.
If the user is stupid enough to use both sockets behind the TV to
maximum its their own fault and they deserve what they get.

Are you genuinely stupid dennis, or just being obtuse because you like
arguing?

Try and comprehend, this has nothing to do with the user, and everything
to do with the designer and installer. If the designer does their job
right, the user can get on and use a system that is flexible, does what
they need, does not give spurious trips. and remains safe.

Having a system which can overheat without tripping something is NOT
safe, is a BAD design, and should NOT be done by anyone who calls
themselves qualified.

Well unless you are talking about the current limit on the double socket
itself (which if you wish to avoid, you will need to use single
sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately protected in a standard ring main.

You might like to mandate that a 32A circuit is dedicated to each and
every double socket, but fortunately its not your decision, and no one
else thinks its a good idea. So you may as well learn to live with it.

Where did you pull that one from? Nobody has mentioned seperate

This is a bit of historic dennis... don't worry about it.

circuits. As long as you can't overheat something. The max load
handleable by any one point in the circuit (in this case the double
socket) should be equal to or more than the protective fuse or breaker.

Not really a logical deduction is it. The circuit can feed far more than
one socket, so there is no point limiting its design current to
something that just one socket can handle.

In which case the socket should either be fused, or be able to handle more. Two sockets at 13A = 26A. We could have 26A fuses in ring mains, and double sockets that are made properly.

As a designer one has the freedom to make sensible choices about
matching the installation to the pattern of use. This is a system that
works remarkably well in practice, and has given the UK the safest
electrical systems in the world.

Don't guess at patterns. Allow for what COULD happen. "Oh the user most
likely won't do this" is just not good enough.

Engineering decisions are frequently made on the balance of probabilities.

Which is why problems arise. Especially when people tend to assume there is a safety margin (and not the other way round!) - for example if food has a sellby date of yesterday, it's most likely just fine.

If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning about
it here.

Why can't he moan about people like you who agree with the incorrect 17th?

Well he can, but its pointless because we don't agree with him. If he
wants something to be different, then he would need to address his
concerns to the people able to change the requirements.

You'd think after 17 editions they would have got it right.

--
http://petersparrots.com
http://petersphotos.com

Light travels faster than sound. This is why some people
appear bright until you hear them speak.

On 07/01/2012 21:29, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm
wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:

On 05/01/2012 20:17, dennis@home wrote:


"John Rumm" wrote in message
o.uk...
On 05/01/2012 11:20, dennis@home wrote:


We are not all tightwads like you dennis...



Why?



You could do with getting a handle on this concept we call "design".
You make an assessment of the typical load, look at the installation
conditions, and then specify an appropriate installation.

What might be appropriate for a socket behind a TV is very different
for one in a utility room where you expect a washing machine and
tumble drier to be installed.

Here we are again.
If the user is stupid enough to use both sockets behind the TV to
maximum its their own fault and they deserve what they get.

Are you genuinely stupid dennis, or just being obtuse because you like
arguing?

Try and comprehend, this has nothing to do with the user, and
everything
to do with the designer and installer. If the designer does their job
right, the user can get on and use a system that is flexible, does what
they need, does not give spurious trips. and remains safe.

Having a system which can overheat without tripping something is NOT
safe, is a BAD design, and should NOT be done by anyone who calls
themselves qualified.

Well unless you are talking about the current limit on the double socket
itself (which if you wish to avoid, you will need to use single
sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately
protected in a standard ring main.

So change all yours to singles if it bothers you.

BTW the circuit topology is not relevant - the situation would be no
different on a radial. It would be no different if you reduced the MCB
size to 16A either.

(there are plenty of other examples of equipment design that take load
diversity into account as well - probably best we don't tell you about
those though ;-))


If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning about
it here.

Why can't he moan about people like you who agree with the incorrect
17th?

Well he can, but its pointless because we don't agree with him. If he
wants something to be different, then he would need to address his
concerns to the people able to change the requirements.

You'd think after 17 editions they would have got it right.

You will never get an standard "right" when its dealing with a
constantly evolving requirement. Patterns of use change, technology
changes and evolves. The law of unintended consequence will often bite!
Hence you get evolution. Things that are proven to work well, stay.
Things that demonstrate real world problems get changed. All that before
you even consider political and other vested interests exerting influence.

anyway, think this one is done to death now...


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

"John Rumm" wrote in message
o.uk...
On 07/01/2012 21:29, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm
wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:

On 05/01/2012 20:17, dennis@home wrote:


"John Rumm" wrote in message
o.uk...
On 05/01/2012 11:20, dennis@home wrote:


We are not all tightwads like you dennis...



Why?



You could do with getting a handle on this concept we call "design".
You make an assessment of the typical load, look at the installation
conditions, and then specify an appropriate installation.

What might be appropriate for a socket behind a TV is very different
for one in a utility room where you expect a washing machine and
tumble drier to be installed.

Here we are again.
If the user is stupid enough to use both sockets behind the TV to
maximum its their own fault and they deserve what they get.

Are you genuinely stupid dennis, or just being obtuse because you like
arguing?

Try and comprehend, this has nothing to do with the user, and
everything
to do with the designer and installer. If the designer does their job
right, the user can get on and use a system that is flexible, does
what
they need, does not give spurious trips. and remains safe.

Having a system which can overheat without tripping something is NOT
safe, is a BAD design, and should NOT be done by anyone who calls
themselves qualified.

Well unless you are talking about the current limit on the double socket
itself (which if you wish to avoid, you will need to use single
sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately
protected in a standard ring main.

So change all yours to singles if it bothers you.


Bloke rewired his own bungalow and had leccy board come round to connect.

Man From Leccy Board looks at wiring behind sockets, only one T&E, where, on
a ring, he would expect to see two (or three if there is a spur involved).
MFLB: " Can't connect. Your ring main isn't a ring, there is only one T&E
going to each socket"
Owner: "It IS a ring. Look in the loft."
MFLB goes in loft: sees ring around edge of loft near roof, *30A joint
boxes* actually onthe ring, with single T&E going off down to each socket
outlet.
MFLB: "Can't connect. At least half the socket outlets must be actually
ON the ring"
MFLB goes away.

An couple of hours later, MFLB gets call from his boss, to go back,
reinspect and connect.

MFLB goes up into loft, to find that each and every 30A jointbox had been
removed, and replaced with a 13A socket outlet, neatly screwed with a box
onto the joists. Each 13A s/o had a spur down into the living area, with one
13A s/o on the end......

MFLB gave up and connected.

On 31/12/2011 12:39, Terry wrote:
On 31/12/2011 12:15, ARWadsworth wrote:
Judith wrote:
Someone posted the following picture on another newsgroup.

http://www.swldxer.co.uk/kitchen.jpg


What a **** hole.


Misty grey tiles - must have been done in the 90's. What colour
is the bathroom suite ?.

Andrew

On 31/12/2011 15:06, johannes wrote:


ARWadsworth wrote:

Judith wrote:
Someone posted the following picture on another newsgroup.

http://www.swldxer.co.uk/kitchen.jpg


(Note the white cable coming out of the LHS of the supply point above
the cooker)

Whilst it is obviously potentially unsafe and stupidity to have
something like this in a kitchen; has the person who did it broken
any regulations?

I suppose if it was the owner of the property who did the wiring,
then it would be their own stupid fault if someone gets an electric
shock - or would the person who made the connection be liable in
anyway?

It's a bloody disgrace.

There is no HP sauce.

The selection of goods on display shows that the people living there
are a bit snobbish. E.g. Ginseng extract - pah!

If that is their diet, then they will needs those Andrews Liver salts,
if that is what they are.

Actually I think you work for the BBC don't you - all that product
placement ..

Cycling group added as the owner of this kitchen frequents that group

"Andrew" wrote in message news
On 31/12/2011 12:39, Terry wrote:
On 31/12/2011 12:15, ARWadsworth wrote:
Judith wrote:
Someone posted the following picture on another newsgroup.

http://www.swldxer.co.uk/kitchen.jpg


What a **** hole.


Misty grey tiles - must have been done in the 90's. What colour
is the bathroom suite ?.

MFI/Hygena cupboards too.
I had the same ones in the early 1990's
Even the knobs are the same.

David Kemper

On Sun, 08 Jan 2012 16:03:05 -0000, Ian wrote:


"John Rumm" wrote in message
o.uk...
On 07/01/2012 21:29, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm
wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:









Having a system which can overheat without tripping something is NOT
safe, is a BAD design, and should NOT be done by anyone who calls
themselves qualified.

Well unless you are talking about the current limit on the double socket
itself (which if you wish to avoid, you will need to use single
sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately
protected in a standard ring main.

So change all yours to singles if it bothers you.


Bloke rewired his own bungalow and had leccy board come round to connect.

Man From Leccy Board looks at wiring behind sockets, only one T&E, where, on
a ring, he would expect to see two (or three if there is a spur involved).
MFLB: " Can't connect. Your ring main isn't a ring, there is only one T&E
going to each socket"
Owner: "It IS a ring. Look in the loft."
MFLB goes in loft: sees ring around edge of loft near roof, *30A joint
boxes* actually onthe ring, with single T&E going off down to each socket
outlet.
MFLB: "Can't connect. At least half the socket outlets must be actually
ON the ring"
MFLB goes away.

An couple of hours later, MFLB gets call from his boss, to go back,
reinspect and connect.

MFLB goes up into loft, to find that each and every 30A jointbox had been
removed, and replaced with a 13A socket outlet, neatly screwed with a box
onto the joists. Each 13A s/o had a spur down into the living area, with one
13A s/o on the end......

MFLB gave up and connected.

ROTFPMSL! Some people just have no common sense whatsoever.

--
http://petersparrots.com
http://petersphotos.com

What does a married man say after sex?
Don't tell my wife.

On Sat, 07 Jan 2012 23:03:20 -0000, John Rumm wrote:

On 07/01/2012 21:29, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm
wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:

On 05/01/2012 20:17, dennis@home wrote:








Are you genuinely stupid dennis, or just being obtuse because you like
arguing?

Try and comprehend, this has nothing to do with the user, and
everything
to do with the designer and installer. If the designer does their job
right, the user can get on and use a system that is flexible, does what
they need, does not give spurious trips. and remains safe.

Having a system which can overheat without tripping something is NOT
safe, is a BAD design, and should NOT be done by anyone who calls
themselves qualified.

Well unless you are talking about the current limit on the double socket
itself (which if you wish to avoid, you will need to use single
sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately
protected in a standard ring main.

So change all yours to singles if it bothers you.

And have half the number of outlets? No.

BTW the circuit topology is not relevant - the situation would be no
different on a radial. It would be no different if you reduced the MCB
size to 16A either.

If the MCB was at or less than the value that the double sockets could handle, it would be fine. Radials could also have their own breakers.

(there are plenty of other examples of equipment design that take load
diversity into account as well - probably best we don't tell you about
those though ;-))

What happened to "safety margins"? This is the exact opposite!

If you are still unhappy about it, why not write to the IET with your
objections and suggestions for the 18th edition? No point moaning about
it here.

Why can't he moan about people like you who agree with the incorrect
17th?

Well he can, but its pointless because we don't agree with him. If he
wants something to be different, then he would need to address his
concerns to the people able to change the requirements.

You'd think after 17 editions they would have got it right.

You will never get an standard "right" when its dealing with a
constantly evolving requirement. Patterns of use change, technology
changes and evolves. The law of unintended consequence will often bite!
Hence you get evolution. Things that are proven to work well, stay.
Things that demonstrate real world problems get changed. All that before
you even consider political and other vested interests exerting influence.

It's very easy to get the standard right. Two sockets mean you can plug in two items with a 13A fuse on each, so the twin socket needs to take 26 amps.

--
http://petersparrots.com
http://petersphotos.com

What does a married man say after sex?
Don't tell my wife.

Ian wrote:
"John Rumm" wrote in message
o.uk...
On 07/01/2012 21:29, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm
wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 00:33:23 -0000, John Rumm
wrote:

On 05/01/2012 20:17, dennis@home wrote:


"John Rumm" wrote in message
o.uk...
On 05/01/2012 11:20, dennis@home wrote:


We are not all tightwads like you dennis...



Why?



You could do with getting a handle on this concept we call
"design". You make an assessment of the typical load, look at
the installation conditions, and then specify an appropriate
installation. What might be appropriate for a socket behind a TV is
very
different for one in a utility room where you expect a washing
machine and tumble drier to be installed.

Here we are again.
If the user is stupid enough to use both sockets behind the TV
to maximum its their own fault and they deserve what they get.

Are you genuinely stupid dennis, or just being obtuse because
you like arguing?

Try and comprehend, this has nothing to do with the user, and
everything
to do with the designer and installer. If the designer does
their job right, the user can get on and use a system that is
flexible, does what
they need, does not give spurious trips. and remains safe.

Having a system which can overheat without tripping something is
NOT safe, is a BAD design, and should NOT be done by anyone who
calls themselves qualified.

Well unless you are talking about the current limit on the double
socket itself (which if you wish to avoid, you will need to use
single sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately
protected in a standard ring main.

So change all yours to singles if it bothers you.


Bloke rewired his own bungalow and had leccy board come round to
connect.
Man From Leccy Board looks at wiring behind sockets, only one T&E,
where, on a ring, he would expect to see two (or three if there is a
spur involved). MFLB: " Can't connect. Your ring main isn't a ring,
there is only one T&E going to each socket"
Owner: "It IS a ring. Look in the loft."
MFLB goes in loft: sees ring around edge of loft near roof, *30A joint
boxes* actually onthe ring, with single T&E going off down to each
socket outlet.
MFLB: "Can't connect. At least half the socket outlets must be
actually ON the ring"
MFLB goes away.

An couple of hours later, MFLB gets call from his boss, to go back,
reinspect and connect.

MFLB goes up into loft, to find that each and every 30A jointbox had
been removed, and replaced with a 13A socket outlet, neatly screwed
with a box onto the joists. Each 13A s/o had a spur down into the
living area, with one 13A s/o on the end......

MFLB gave up and connected.

Am I the only one here to be caught out connecting up the supply without the
LECs permission?

That's twice in the last 12 months.


--
Adam

On Sun, 8 Jan 2012 20:36:27 -0000, "David Kemper"
wrote:

Cycling group added as the owner of this kitchen frequents that group

"Andrew" wrote in message news
Is the bicycle relevant?

--
Frank Erskine

On Sun, 08 Jan 2012 23:20:04 -0000, ARWadsworth wrote:

Ian wrote:
"John Rumm" wrote in message
o.uk...
On 07/01/2012 21:29, Lieutenant Scott wrote:
On Fri, 06 Jan 2012 21:58:41 -0000, John Rumm
wrote:

On 06/01/2012 03:00, Lieutenant Scott wrote:








Well unless you are talking about the current limit on the double
socket itself (which if you wish to avoid, you will need to use
single sockets), then we are actually in agreement.

That IS what I'm talking about. Double sockets are not adequately
protected in a standard ring main.

So change all yours to singles if it bothers you.


Bloke rewired his own bungalow and had leccy board come round to
connect.
Man From Leccy Board looks at wiring behind sockets, only one T&E,
where, on a ring, he would expect to see two (or three if there is a
spur involved). MFLB: " Can't connect. Your ring main isn't a ring,
there is only one T&E going to each socket"
Owner: "It IS a ring. Look in the loft."
MFLB goes in loft: sees ring around edge of loft near roof, *30A joint
boxes* actually onthe ring, with single T&E going off down to each
socket outlet.
MFLB: "Can't connect. At least half the socket outlets must be
actually ON the ring"
MFLB goes away.

An couple of hours later, MFLB gets call from his boss, to go back,
reinspect and connect.

MFLB goes up into loft, to find that each and every 30A jointbox had
been removed, and replaced with a 13A socket outlet, neatly screwed
with a box onto the joists. Each 13A s/o had a spur down into the
living area, with one 13A s/o on the end......

MFLB gave up and connected.

Am I the only one here to be caught out connecting up the supply without the
LECs permission?

That's twice in the last 12 months.

Which bit are you referring to?

--
http://petersparrots.com
http://petersphotos.com

Jack and Jill went up the hill
And planned to do some kissing.
Jack made a pass, and grabbed her ass
Now two of his teeth are missing.

On Wed, 04 Jan 2012 17:50:18 -0000, Ian wrote:


"Tim Streater" wrote in message
...
In article ,
John Rumm wrote:

On 04/01/2012 15:20, Lieutenant Scott wrote:
On Wed, 04 Jan 2012 13:29:16 -0000, John Williamson
wrote:

Lieutenant Scott wrote:

Not a lot to do with the thickness of the prongs - they are capable
of
carrying WELL over 30A in all probability.

Just how thick is the actual conductor inside the sleeved bit?

It has a greater area than the wires connecting to the plug, and with
a
*much* lower resistance than the connection from the wire to the pin,
or
the wire in the fuse.

As has already been said here, the weak points of *any* temporary
mains
connection are the fuse, the connections to the fuse, the connections
to
the wires, and the sprung contacts in the socket.

Recent (within the last fifteen years or so) improvements include
welding the wire to the pins inside the plug, which was introduced to
improve the reliability of pre-wired plugs, and improving the design
of
the fuseholder from the old style with two narrow prongs contacting
the
fuse to the current standard of two wider, shaped holders, and a
holder
for the fuse which means that it can be changed without tools.

Honestly, this just happened by chance, and has nothing to do with me
already being in this thread!

I plugged this into the mains and wondered why the laptop wasn't
charging properly, it kept going off. I removed the plug, intending to
try another lead, and left the neutral prong in the socket!

http://petersphotos.com/temp/plug.jpg

Bring back the big old British ones with hefty round pins! Any reason
we
changed from those?

They were unfused and hence could not be used on a high power circuits,
and they were unshuttered with all the risks that that entails. As the
modern home is stuffed with ever more low power devices, the need for
sockets with ever greater current capacity would seem to be waning.

And there were several physical sizes. So we had two sizes of socket at
the wall. I remember these clearly from 1951 or so. See BS 546.

2pin 3A
3pin 3A
3pin 5A
3pin 15A
3pin (round pin, fused pin) 13A
Clock outlet.

I may have left one or two out.

I only remember the 5A and 15A round pins, but then I was born in 75 - maybe the others went away earlier than that?

I remember a woman telling me that she had to get her house rewired to change to 13A sockets. She was convinced that you could not possibly draw 13 amps from a 15 amp outlet, as it was a different kind of electricity. And those little adaptors she had were converting it.

Today, we have 3 pin "13"A.
(which sometimes can be seen in two vertical current-carrying, with
horizontal earth pin, configuration. Often used where there is a need for a
socket outlet, where you don't want any unauthorised items being pugged in).

You mean someone stealing electricity for clay-making? http://youtu.be/1Bi63Hi51sQ

--
http://petersparrots.com
http://petersphotos.com

Why is the front of an aeroplane called a cockpit?
If you have female pilots do you call it a pussypit?

"Lieutenant Scott" wrote in message
newsp.v7sfueczytk5n5@i7-940...

8

Someone needed to snip it so I did.

I don't know of any industrial electricians that would under rate the cables
or fit doubles on a 32A breaker.
This being because its unsafe to assume diversity will result in safe
operation.
So we are back to the old rules for domestic work:

Its probably safe but it isn't designed to be safe its probably safe.
The user probably isn't going to overload anything even though its easy to
do.
We can blame it on the user if it goes wrong for doing something he probably
shouldn't have.
We don't have to work to the *minimum* standard specified by the "regs" (but
we make more profit and have to think less if we do).

The "regs" are probably wrong, they have been in the past and will be in the
future. For example there have been various improvements to ring circuits
over the issues all slowly leading to a better probability of them being
safe.
The users of the stuff from old issues are probably less safe but its their
own fault and they deserve what they get.

On Mon, 09 Jan 2012 09:19:31 -0000, dennis@home wrote:



"Lieutenant Scott" wrote in message
newsp.v7sfueczytk5n5@i7-940...

8

Someone needed to snip it so I did.

I don't know of any industrial electricians that would under rate the cables
or fit doubles on a 32A breaker.
This being because its unsafe to assume diversity will result in safe
operation.
So we are back to the old rules for domestic work:

I know of a school which just had them fitted by industrial electricians. I did have to moan at them to change the breakers to slower ones as they tripped every time someone plugged in a trolley of laptop chargers.

Its probably safe but it isn't designed to be safe its probably safe.
The user probably isn't going to overload anything even though its easy to
do.
We can blame it on the user if it goes wrong for doing something he probably
shouldn't have.
We don't have to work to the *minimum* standard specified by the "regs" (but
we make more profit and have to think less if we do).

The "regs" are probably wrong, they have been in the past and will be in the
future. For example there have been various improvements to ring circuits
over the issues all slowly leading to a better probability of them being
safe.
The users of the stuff from old issues are probably less safe but its their
own fault and they deserve what they get.

Indeed. Why do we have to learn from mistakes instead of thinking and getting it right the first time? It's nearly as bad as release versions of software that are beta quality.

--
http://petersparrots.com
http://petersphotos.com

When a man steals your wife, there is no better revenge than to let him keep her.

On Jan 8, 11:46*pm, Frank Erskine
wrote:
On Sun, 8 Jan 2012 20:36:27 -0000, "David Kemper"

wrote:
Cycling group added as the owner of this kitchen frequents that group

"Andrew" *wrote in messagenews

Is the bicycle relevant?

Very.

MBQ

"dennis@home" wrote in message
eb.com...


"Lieutenant Scott" wrote in message
newsp.v7sfueczytk5n5@i7-940...

8

Someone needed to snip it so I did.

I don't know of any industrial electricians that would under rate the
cables or fit doubles on a 32A breaker.
This being because its unsafe to assume diversity will result in safe
operation.
So we are back to the old rules for domestic work:

Its probably safe but it isn't designed to be safe its probably safe.
The user probably isn't going to overload anything even though its easy to
do.
We can blame it on the user if it goes wrong for doing something he
probably shouldn't have.
We don't have to work to the *minimum* standard specified by the "regs"
(but we make more profit and have to think less if we do).

The "regs" are probably wrong, they have been in the past and will be in
the future. For example there have been various improvements to ring
circuits over the issues all slowly leading to a better probability of
them being safe.
The users of the stuff from old issues are probably less safe but its
their own fault and they deserve what they get.

I doubt if many people are going to pore over each issue of the regs as they
come out, and have their installations modified accordingly.

Wouldn't surprise me if there was some slip-joint conduit kiccking around
somewhere, with rubber-insulated cables in it. 3/029 possibly.... or even
1/014 !!