Hi,

About a week ago there was an interesting thread about someone looking
for a vertical cooker switch with integral socket. I wasn't sure if
anyone was still watching that thread, so thought I would start a new
one.

Some time ago I was looking for a vertical plate with socket and all I
could find was the one listed on the TLC web site. Like the other
poster, I didn't buy it because it was ugly! I'm pleased to hear the
manufacturer has made it prettier.

What is the general feeling about these switches with sockets? Are
they seen as a bad thing? IIRC they are supposed to be used for loads
of 5A or less. Does this limit their usefulness?

I suppose you could use it for a food processor or similar low-current
kitchen appliance but presumably you cannot use it for heavier loads,
such as a kettle, toaster, or a vegetable steamer. Or does diversity
mean that big loads for short periods are ok?

The old thread suggested taking a socket on a spur from the cooker
switch. Is this within the regs? I have seen a double socket spurred
off a cooker switch; that can't be right surely?

I wanted to ask: where should the cooker switches be positioned? Are
they there only to isolate the cooker if you are cleaning, repairing,
or replacing it? Or are they also to switch off the cooker in an
emergency (i.e. it catches fire)?

The reason I ask is that I have an electric hob and an electric oven
next to each other. I have two switches: one to the left of the hob
and one to the left of the oven. The switch for the oven is behind the
hob. I'm wondering if this is bad? Is there a risk of steam from the
hob getting into the switch? Would I be able to reach over the hob to
switch off the oven if the oven caught fire? Should I be thinking of
relocating the switch for either of these reasons?

Are there any rules on how far away the switch should be from the
appliance?

Is there any reason to have the large switches or is it that a double
box gives you more room for the larger cable?

TIA

On 27/08/2012 21:16, Fred wrote:
Hi,

About a week ago there was an interesting thread about someone looking
for a vertical cooker switch with integral socket. I wasn't sure if
anyone was still watching that thread, so thought I would start a new
one.

Some time ago I was looking for a vertical plate with socket and all I
could find was the one listed on the TLC web site. Like the other
poster, I didn't buy it because it was ugly! I'm pleased to hear the
manufacturer has made it prettier.

What is the general feeling about these switches with sockets? Are
they seen as a bad thing? IIRC they are supposed to be used for loads
of 5A or less. Does this limit their usefulness?

You can use them for any load you like - there is no limitation.

The 5A bit comes from when making a diversity assessment for the circuit
- that it is unlikely that the socket would add more than 5A sustained
load.

I suppose you could use it for a food processor or similar low-current
kitchen appliance but presumably you cannot use it for heavier loads,
such as a kettle, toaster, or a vegetable steamer. Or does diversity
mean that big loads for short periods are ok?

Yup. In fact the 32A MCB and 6mm^2 cable means its more than man enough
for anything you can plug into a socket.

The old thread suggested taking a socket on a spur from the cooker
switch. Is this within the regs? I have seen a double socket spurred
off a cooker switch; that can't be right surely?

Can't see it being a major problem. Its slighty unconventional. You can
have a double socket spurred from a 32A radial or ring designed for
normal sockets. Fault protection is provided by the MCB at the circuit
origin, and overload protection by the nature of the load (i.e. just one
individual socket fitting (even if its a double)) and that assumes you
have dropped a cable size or two for the spur. So in general nothing bad
is going to happen. However use common sense. If that double socket was
likely to power a washing machine and dishwasher, then the chances of
getting nuisance trips on the cooker increase.

I wanted to ask: where should the cooker switches be positioned? Are
they there only to isolate the cooker if you are cleaning, repairing,
or replacing it? Or are they also to switch off the cooker in an
emergency (i.e. it catches fire)?

Both. They should be within 2m of the device the control.

The reason I ask is that I have an electric hob and an electric oven
next to each other. I have two switches: one to the left of the hob
and one to the left of the oven. The switch for the oven is behind the
hob. I'm wondering if this is bad? Is there a risk of steam from the
hob getting into the switch? Would I be able to reach over the hob to
switch off the oven if the oven caught fire? Should I be thinking of
relocating the switch for either of these reasons?

Having a switch over a hob is not ideal - not least from the point of
view of the steaming that it may get.

Are there any rules on how far away the switch should be from the
appliance?

Yes - guidelines certainly. The OSG (copied from 16th edition text) says
"A circuit of rating exceeding 15 A but not exceeding 50 A may
supply two or more cooking appliances where these are
installed in one room. The control switch or cooker control
unit should be placed within two metres of the appliance, but
not directly above it. Where two stationary cooking appliances
are installed in one room, one switch may be used to control
both appliances provided that neither appliance is more than
two metres from the switch."

Is there any reason to have the large switches or is it that a double
box gives you more room for the larger cable?

Most of the switches with socket are double box sized. Hence they make
switches alone that will also fit that form factor. The depth of the box
is perhaps more important since it makes wiring with heavier grades of
T&E easier.


--
Cheers,

John.

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

On Mon, 27 Aug 2012 23:28:18 +0100, John Rumm
wrote:

You can use them for any load you like - there is no limitation.

The 5A bit comes from when making a diversity assessment for the circuit
- that it is unlikely that the socket would add more than 5A sustained
load.


Thanks. I guess the key word here is "sustained". A toaster or kettle
on for a brief period would be ok.

Having a switch over a hob is not ideal - not least from the point of
view of the steaming that it may get.

The OSG (copied from 16th edition text) says
"A circuit of rating exceeding 15 A but not exceeding 50 A may
supply two or more cooking appliances where these are
installed in one room. The control switch or cooker control
unit should be placed within two metres of the appliance, but
not directly above it. Where two stationary cooking appliances
are installed in one room, one switch may be used to control
both appliances provided that neither appliance is more than
two metres from the switch."

I was thinking about moving the switch from behind the hob but reading
the guidelines you posted, an alternative may be to remove that switch
all together and use one switch for both the hob and the oven.

Most of the switches with socket are double box sized. Hence they make
switches alone that will also fit that form factor.

I don't know about that; the big switches I have seen are vertical but
switches with sockets always seem to be horizontal, hence the other
poster's difficulty in finding a vertical switch with socket.

Thanks again.

On 28/08/2012 08:42, Fred wrote:
On Mon, 27 Aug 2012 23:28:18 +0100, John Rumm
wrote:

You can use them for any load you like - there is no limitation.

The 5A bit comes from when making a diversity assessment for the circuit
- that it is unlikely that the socket would add more than 5A sustained
load.


Thanks. I guess the key word here is "sustained". A toaster or kettle
on for a brief period would be ok.

Yup.

Its part of a game of statistics really - averaged loads over time. Its
why you can stick 15kW (65A) of cooker on a 32A circuit, and rarely if
every have a problem in a domestic setting. (most cookers will pull less
than 20A most of the time)

Having a switch over a hob is not ideal - not least from the point of
view of the steaming that it may get.

The OSG (copied from 16th edition text) says
"A circuit of rating exceeding 15 A but not exceeding 50 A may
supply two or more cooking appliances where these are
installed in one room. The control switch or cooker control
unit should be placed within two metres of the appliance, but
not directly above it. Where two stationary cooking appliances
are installed in one room, one switch may be used to control
both appliances provided that neither appliance is more than
two metres from the switch."

I was thinking about moving the switch from behind the hob but reading
the guidelines you posted, an alternative may be to remove that switch
all together and use one switch for both the hob and the oven.

Yup, that is not an uncommon way of doing it.

Most of the switches with socket are double box sized. Hence they make
switches alone that will also fit that form factor.

I don't know about that; the big switches I have seen are vertical but
switches with sockets always seem to be horizontal, hence the other
poster's difficulty in finding a vertical switch with socket.

Thanks again.



--
Cheers,

John.

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

On 28/08/2012 13:01, Huge wrote:
On 2012-08-28, John Rumm wrote:
On 28/08/2012 08:42, Fred wrote:
On Mon, 27 Aug 2012 23:28:18 +0100, John Rumm
wrote:

You can use them for any load you like - there is no limitation.

The 5A bit comes from when making a diversity assessment for the circuit
- that it is unlikely that the socket would add more than 5A sustained
load.


Thanks. I guess the key word here is "sustained". A toaster or kettle
on for a brief period would be ok.

Yup.

Its part of a game of statistics really - averaged loads over time. Its
why you can stick 15kW (65A) of cooker on a 32A circuit, and rarely if
every have a problem in a domestic setting. (most cookers will pull less
than 20A most of the time)

The evening of the day we moved into this house, we had every light in
the place on while we rushed from room to room. After a couple of hours
it tripped the RCD, plunging us conveniently into darkness in a house
where we weren't sure where the fusebox was, didn't know where the piles
of boxes and furniture were, didn't know our way round in the dark and
weren't sure where the torch was. Sigh.

Still, that was better than the morning, when we arrived to find no
electricity at all. (It had stood empty for some months and water had
got into the *non-submersible* connector for the cesspit pump and tripped
the main house RCD. Still, at least the removal men thought it was
funny, watching me bail out the cesspit with a bucket on a rope to get
to the connector. Bigger sigh.)

One of the reasons I like to give any circuits outside their own CU and
RCD etc. It may not remove the possibility of needing to bail out the
cesspit, but at least you get to choose the time, and know the shower
should be working when you are done! ;-))


--
Cheers,

John.

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

On 28/08/2012 13:29, Owain wrote:
On Aug 28, 1:01 pm, Huge wrote:
The evening of the day we moved into this house, we had every light in
the place on while we rushed from room to room.

Diversity is not applied to lighting circuits, for that reason.

They had tried it in this house when we moved in... turned all the
downstairs lights on, and they all went off after 15 mins!

--
Cheers,

John.

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

Huge wrote:
On 2012-08-28, John Rumm wrote:
On 28/08/2012 08:42, Fred wrote:
On Mon, 27 Aug 2012 23:28:18 +0100, John Rumm
wrote:

You can use them for any load you like - there is no limitation.

The 5A bit comes from when making a diversity assessment for
the circuit - that it is unlikely that the socket would add
more than 5A sustained load.


Thanks. I guess the key word here is "sustained". A toaster or
kettle on for a brief period would be ok.

Yup.

Its part of a game of statistics really - averaged loads over time.
Its why you can stick 15kW (65A) of cooker on a 32A circuit, and
rarely if every have a problem in a domestic setting. (most cookers
will pull less than 20A most of the time)

The evening of the day we moved into this house, we had every light in
the place on while we rushed from room to room. After a couple of
hours it tripped the RCD, plunging us conveniently into darkness in a
house where we weren't sure where the fusebox was, didn't know where
the piles of boxes and furniture were, didn't know our way round in
the dark and weren't sure where the torch was. Sigh.


Which tripprd?
The RCD or the fuse?
--
Adam

Huge wrote:
On 2012-08-28, ARWadsworth wrote:
Huge wrote:
On 2012-08-28, John Rumm wrote:
On 28/08/2012 08:42, Fred wrote:
On Mon, 27 Aug 2012 23:28:18 +0100, John Rumm
wrote:

You can use them for any load you like - there is no
limitation.

The 5A bit comes from when making a diversity assessment for
the circuit - that it is unlikely that the socket would add
more than 5A sustained load.


Thanks. I guess the key word here is "sustained". A toaster or
kettle on for a brief period would be ok.

Yup.

Its part of a game of statistics really - averaged loads over
time. Its why you can stick 15kW (65A) of cooker on a 32A
circuit, and rarely if every have a problem in a domestic
setting. (most cookers will pull less than 20A most of the time)

The evening of the day we moved into this house, we had every
light in the place on while we rushed from room to room. After a
couple of hours it tripped the RCD, plunging us conveniently into
darkness in a house where we weren't sure where the fusebox was,
didn't know where the piles of boxes and furniture were, didn't
know our way round in the dark and weren't sure where the torch
was. Sigh.


Which tripprd?
The RCD or the fuse?

TBH, I can't remember, it was 20 years ago. And we have MCBs. I think
it was the lighting MCB that tripped, not the RCD (which is a whole
house one). It's never done it again, so I always assumed it was a
diversity problem.

[Light bulb over head!]

Definitely the MCB, because naughty me bought a larger one to replace
the downstairs lighting one, to find that I'd been outthought by the
designers, because the bases aren't compatible. It's still in the
cupboard, somewhere.

Well if you have never had all the lights on again:-)

Or a lamp blew, that would take out the MCB.

BTW, If you want a bigger MCB let me know. I'll probably have one (you can
have it for free).
--
Adam