Converting bathroom pull-cord to external lightswitch

[waterox]

I would like to convert a bathroom pull-cord switch to a standard wall-flush lightswitch just outside the bathroom door.

Is it possible to attach the wires that hang from the bathroom ceiling (where the pullcord mechanism has been disconnected) to some kind of junction box, and run a length of wire from that to the new switch?

Is there anything else I need to be aware of?

I am planning to use external trunking the extension.


I am replacing the pullswitch as the original one made a very loud acoustic CLIK-KUNNG sound, and the 'silent' dimmer version plays havoc with recording through a valve guitar amp, creating a very loud buzzing when the light is on. Dimmer switches are a known evil for recording setups. I tried bypassing the copper coil mounted on its circuit board, but this killed the mechanism (possibly due to static electricity as it has a chip etc)

 

[ericmark]

To follow the letter of the law you need to inform the Local council building control and pay their fee under Part P or employ a registered electrician.
If the joint is accessible you can use any junction box if not it has to be special screw less type sold for where there is no access. If surface than not too much of a problem but if buried in the wall then either ali-tube cables or RCD required.
Sorry I don't like it either but that's the way it has gone.
Eric

 

[Spark123]

Is there access from above? How difficult to replace the length of wire back to the light (or where it comes from) with a longer new piece?
I should maybe mention that the 17th edition requires all circuits in a bathroom to be RCD protected, if you are adding to wiring within the zones of a bathroom then it should be notified to your LABC in advance and a fee paid (unless you are replacing a damaged piece of cable on a like for like).
Thyristor devices - especially cheapy ones with no/little mains suppression are a pain for causing buzzing on audio systems, I have a similar issue with a theatre when the house lights are mid position they cause a hum on the audio system. The more expensive betapacks don't cause the same issue. (More expensive means £600 ish for 6 x 10A channels)
The item you shorted out is an inductor - iirc this is installed in an attempt to make the current lag the voltage to try and bring it back to a sort of normal sin wave as the dimming is created by clipping the sin wave - it will also help the triac as full current will not be available instantly. Taking it out won't help it!. The only thing I'd imagine would help with a dimmer switch is more mains filtering which means more inductors/capacitor networks.

 

[ban-all-sheds]

Is there access from above? How difficult to replace the length of wire back to the light (or where it comes from) with a longer new piece?

If there's access from above, maybe relocating the switch so that it's fixed to a piece of wood screwed to the joists with just the cord passing through the ceiling would be the answer. The noise problem is caused by the ceiling acting as a sounding board...

I should maybe mention that the 17th edition requires all circuits in a bathroom to be RCD protected,

But he's not creating any new bathroom circuits.

if you are adding to wiring within the zones of a bathroom then it should be notified to your LABC in advance and a fee paid.

He might not be - depends where the switch is.

 

[Spark123]

Adding to or altering an existing circuit would mean compliance with the 17th edition though.
I did say if

 

[ban-all-sheds]

Adding to or altering an existing circuit would mean compliance with the 17th edition though.

Indeed.

For the additions or alterations.

So any new concealed cabling needs to comply with the 17th requirements for concealed cables.

Any new bathroom circuits would need to comply with the 17th requirements for bathroom circuits.

But simply working on an existing bathroom circuit does not mean that the existing circuit has to be brought up to the standards of the 17th...

 

[Spark123]

How would you RCD protect a light switch cable?

 

[ban-all-sheds]

I might not - if I was adding a concealed cable to a circuit which I didn't want to put on an RCD I might well use a cable type which meant that RCD protection was not required.

 

[Spark123]

Even if part of the addition includes altering a circuit supplying equipment in a location containing a bathtub or shower basin?

 

[ban-all-sheds]

So if you added a new light in a bedroom, in one of the almost-every-house-in-the-country houses where the same lighting circuit serves the bathroom, would you say that it had to go onto an RCD because it also serves the bathroom?

As I see it the situation is straightforward.

The work that you do should comply with the Wiring Regulations.

So if you are not creating a bathroom circuit, or extending one into the bathroom that did not go there before then you don't have to add an RCD to what's already there.

And it's not just I who thinks that: http://www.voltimum.co.uk/news/9702...urbishments-17th-Edition-updating-needed.html

 

[Spark123]

No - I am not saying that.
I am saying if I was adding to a bathroom light circuit i.e. adding a length of cable to the switch drop within the location then I would ensure that my work complies with the 17th edn regs.
If this requires it to be RCD protected then so be it.

If I was adding to a bedroom light and it included concealled cables then yes - it would need to be RCD protected if I was using unprotected twin and earth in the zones.

 

[ban-all-sheds]

No - I am not saying that.
I am saying if I was adding to a bathroom light circuit i.e. adding a length of cable to the switch drop within the location then I would ensure that my work complies with the 17th edn regs.
If this requires it to be RCD protected then so be it.

If the length of cable you are adding is concealed within a wall or partition at a depth of <50mm then RCD protection is one of the options you should employ. You always have the choice of adopting one of the other methods prescribed.

But that's nothing to do with it being in a bathroom - you'd have to do that no matter where it was.

If I was adding to a bedroom light and it included concealled cables then yes - it would need to be RCD protected if I was using unprotected twin and earth in the zones.

The same applies in a bathroom. And only the same applies in a bathroom.

The principle to which everybody subscribed before the 17th, i.e. that new regulations are not retroactive still applies - there is no requirement to bring an existing circuit in a special location into compliance with the current regulations which apply to circuits in special locations.

If you add or change a switch drop you are not creating a circuit in a special location, so you are not bound to ensure that the circuit ends up in compliance with the regulations which apply to the circuit.

I would ensure that my work complies with the 17th edn regs.

Your work comprises only the switch drop cable, and there are no extra regulations for that just because it is in a bathroom.

 

[Spark123]

As you know all circuits in a bathroom need to be RCD protected to comply with the 17th edition regs.
So if I added a switch drop cable to a circuit in a bathroom then that switch drop cable would need to be RCD protected, even if I was to use SWA, MICC or some other cable which is permitted as a concealed cable without additional protection the fact it is in a bathroom requires it to be RCD protected.
How can you RCD protect a switch drop without protecting the original circuit though?

 

[ban-all-sheds]

As you know all circuits in a bathroom need to be RCD protected to comply with the 17th edition regs.

Yes - but the circuit in the bathroom is not your work.

You did not install the circuit.

You were not, and do not become, responsible for compliance at the circuit level.

So if I added a switch drop cable to a circuit in a bathroom then that switch drop cable would need to be RCD protected, even if I was to use SWA, MICC or some other cable which is permitted as a concealed cable without additional protection the fact it is in a bathroom requires it to be RCD protected.

And that is where I believe, with no shred of doubt, that you are completely wrong.

A switch drop cable is not a circuit, therefore the regulations which apply to circuits don't apply to the switch drop.

How can you RCD protect a switch drop without protecting the original circuit though?

You can't, but then you'd have that problem no matter where you added a switch drop.

 

[Spark123]

I am responsible for what I do and put my name on the bottom of the piece of paper to say that my work complies with the current regs.
Part of that circuit in the bathroom may not be my work however the addition to the circuit is. If that addition, alteration etc is in the bathroom then it will need to be RCD protected for my work to comply with the 17th.