Two way switching

[Barney78]

In my bedroom there are two switches for the ceiling light, both of which have to be on for the light to work. This is because it is wired up in a 4 way junction box with one switch either side of the light with no earthing(part of the reason i want to change it).

Ideally i'd like to wire it up so that the 2 switches work independently, which would be fine, except that the cable to one of the switches (the one on the neutral side of the light) is plastered in to a chase in the wall and is only twin and earth. We've only just finished decorating the bedroom so i really dont want to pull it out. Does anyone know a way i can get this working or am i stuck with it until the next time we redecorate?

 

[plugwash]

you can connect the switches in paralell which would bring the light on if either switch was on

but if you want two way switching you either have to replace the cable or use some form of changeover contactors (which would do the job but would not come cheap

 

[ban-all-sheds]

Barney - are you saying that you've got a switch in the live feed to the light, and one in the neutral?

[code:1]
/ /
L -----/ o-------(X)------/ o---------N

[/code:1]

If so, this is a Very Bad Thing....

 

[plugwash]

its bad but its not hugely dangerous the worst it will do is leave the light live when its off

a large portion of europe uses reverseable plugs and sockets anyway

 

[securespark]

its bad but its not hugely dangerous the worst it will do is leave the light live when its off

a large portion of europe uses reverseable plugs and sockets anyway

Plug - can I believe my ears?

It IS bad, & hugely dangerous. SP switches should only operate in the live conductor, don't you know that?

 

[Barney78]

In the interests of not frying myself or burning the house down i've decided to disconnect the second switch above the bed and turn it back in to a single switched circuit until such a time that i feel like ripping off all the nice new wallpaper and running the 3 core and earth down to it. I might even go crazy and put it inside some trunking so its not stuck there for eternity.

 

[plugwash]

its bad but its not hugely dangerous the worst it will do is leave the light live when its off

a large portion of europe uses reverseable plugs and sockets anyway

Plug - can I believe my ears?

It IS bad, & hugely dangerous. SP switches should only operate in the live conductor, don't you know that?

i know its bad practice

however i can't see how a light with just live connected is and more dangerous than a light that is left on

half the time in bathroom lights you end up cahngeing the bulb live because you can't tell whether a pull cord is on or off i really don't see how this situation he has is any worse

 

[securespark]

SAFETY, Plug. That's why.
There are at least some areas of the regs that are crystal and that all sparks agree on: this is one of them.

You wire all SP switches in the phase, because that is convention, in the same way (for example) that you would not fit a plateswitch in the bathroom in Zone 2 because it is convention.

130-05-01 A single pole fuse, switch or cb shall be inserted in the phase conductor only.