In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?
--
Peter.
The gods will stay away
whilst religions hold sway

In article ,
PeterC wrote:
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something
like a cooker point but with a suitable switch.

Any pointers please?

Think you'll be lucky to find what you want - but does it have to be DP?
If single pole a 20 amp two way switch will do what you want.

--
*The modem is the message *

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

Dave Plowman (News)
wibbled on Thursday 22 July 2010 13:50

In article ,
PeterC wrote:
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something
like a cooker point but with a suitable switch.

Any pointers please?

Think you'll be lucky to find what you want - but does it have to be DP?
If single pole a 20 amp two way switch will do what you want.


Other than panel switches, it is an unusual configuration for an accessory
and I don't think the OP will find one either...

Assuming the OP really does want DP, contactors might be an option.

--
Tim Watts

Managers, politicians and environmentalists: Nature's carbon buffer.

"PeterC" wrote in message
...
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?
--
Peter.


How about a simple 20A dp switch in the loft to feed the heater? When you
are working in the loft then just turn the heater off with this switch.

Other options would be to use a contactor or as Dave Plowman has pointed out
use a 20A 2 way switch (it would probably have to be a grid one though).

Cheers

Adam

In article 6xX1o.34420$0e3.1053@hurricane,
"ARWadsworth" writes:

"PeterC" wrote in message
...
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?

How about a simple 20A dp switch in the loft to feed the heater? When you
are working in the loft then just turn the heater off with this switch.

Other options would be to use a contactor or as Dave Plowman has pointed out
use a 20A 2 way switch (it would probably have to be a grid one though).

Or plug the heater in to a socket in the loft, which you unplug to use
for something else.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

ARWadsworth wrote:
wrote in message
...
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?
--
Peter.


How about a simple 20A dp switch in the loft to feed the heater? When you
are working in the loft then just turn the heater off with this switch.

Other options would be to use a contactor or as Dave Plowman has pointed out
use a 20A 2 way switch (it would probably have to be a grid one though).

Cheers

Adam


A toggle switch mounted of a standard blanking plate fitted to a
suitable deep back box. Don't forget to earth the box.
You can get toggle switches with screw terminals.
RS/Farnell/CPC etc

Bob

On Thu, 22 Jul 2010 18:05:06 +0100, Bob Minchin wrote:

ARWadsworth wrote:
wrote in message
...
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?
--
Peter.


How about a simple 20A dp switch in the loft to feed the heater? When you
are working in the loft then just turn the heater off with this switch.

Other options would be to use a contactor or as Dave Plowman has pointed out
use a 20A 2 way switch (it would probably have to be a grid one though).

Cheers

Adam


A toggle switch mounted of a standard blanking plate fitted to a
suitable deep back box. Don't forget to earth the box.
You can get toggle switches with screw terminals.
RS/Farnell/CPC etc

Bob

That was the tempting way as I have a few of those (also 20A relay, 40A SSR
etc.).
--
Peter.
The gods will stay away
whilst religions hold sway

On Jul 22, 1:35*pm, PeterC wrote:
In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing).

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?

Its normal for the total possible load on sockets to far exceed the
cable rating and fuse protection. This isn't a problem, and if you
really plugged excessive loads in, first there's a safety margin in
the cable, and second the 15A mcb would trip if the overload were
significant and sustained. No switch needed.


NT

On Jul 22, 2:34*pm, NT wrote:
On Jul 22, 1:35*pm, PeterC wrote:

In the loft there's a run of 2.5 FT&E that goes to a heater point in the
bathroom. I'd like to leave the heater point wired in but would like a
couple of sokets in the loft (inspection lamp, vac, that sort of thing)..

Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

There are plenty of toggle or rocker switches that would do the job - I
have some - but a metal toggle switch in a box...?

The only others that I've found are grid switches; I'd like something like
a cooker point but with a suitable switch.

Any pointers please?

Its normal for the total possible load on sockets to far exceed the
cable rating and fuse protection. This isn't a problem, and if you
really plugged excessive loads in, first there's a safety margin in
the cable, and second the 15A mcb would trip if the overload were
significant and sustained. No switch needed.

NT

If you really want to be strange and fit a selector switch, single
pole is fine.


NT

On Jul 22, 1:35*pm, PeterC wrote:
Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

You have Type-1 MCB? Cor, I thought only I had stuff that old :-)


This is a non-issue unless you run the cleaner for 30-60min.

A 3kW heater will cycle on its thermostat, but assuming continuous
that corresponds to 4400W or 18A which can be drawn for some time even
on a Type-1 15A MCB or Type-B 16A MCB.

Type B
1.13 * In = 1hr which is 18.1A for a 16A MCB.
1.45 * In = 1hr which is 23.2A for a 16A MCB.
2.55 * In = 1min which is 40.8A for a 16A MCB.

Hence even a seemingly meagre 20A protected radial can handle a lot of
appliances with diversity.
Conversely a short circuit of 5 * In (80A for Type-B 16A MCB) will
cause near instantaneous 0.1s disconnection (fast electromagnetic
operation rather than leisurely thermal bimetallic strip operation).

On Thu, 22 Jul 2010 16:39:45 -0700 (PDT), js.b1 wrote:

On Jul 22, 1:35*pm, PeterC wrote:
Rather not have the chance of someone running a 3kW heater and 1400W vac
via a 15A MCB, so wondered about a switch to mount in the loft to enable
only one outlet at a time.

You have Type-1 MCB? Cor, I thought only I had stuff that old :-)

OK, just actually had a look at it (I haven't used the heater for several
years and had forgotten about the availability of the feed in the loft) and
it's actually 20A!
Given the details below - thank you - I reckon that I don't really have to
worry.

This is a non-issue unless you run the cleaner for 30-60min.

Probably wouldn't do that now, but during the clean-up it was on for about
2 hours during one session.

A 3kW heater will cycle on its thermostat, but assuming continuous
that corresponds to 4400W or 18A which can be drawn for some time even
on a Type-1 15A MCB or Type-B 16A MCB.

Type B
1.13 * In = 1hr which is 18.1A for a 16A MCB.
1.45 * In = 1hr which is 23.2A for a 16A MCB.
2.55 * In = 1min which is 40.8A for a 16A MCB.

Hence even a seemingly meagre 20A protected radial can handle a lot of
appliances with diversity.
Conversely a short circuit of 5 * In (80A for Type-B 16A MCB) will
cause near instantaneous 0.1s disconnection (fast electromagnetic
operation rather than leisurely thermal bimetallic strip operation).

OK, looks as if I don't need to worry about it. It's OK for me, as I'm
aware of loadings etc., but I was considering future use by those who like
3 appliances in 1 socket.

Many thanks for the various suggestions - some good ideas if I do need to
do this elsewhere.
--
Peter.
The gods will stay away
whilst religions hold sway