2 way lightning

paulbristol · 3 Jan 2020

Hi,

I've got two way switching on my hall way. I want to remove this and go to a single switch.

In each switch box, I've got two T&E however one of the T&E has the black wire snipped off. The red from this T&E goes into COM.

The black and red from the other goes into L1 & L2 on both switch boxes.

In the ceiling rose, I only have a single T&E.

Am I right in thinking that most likely the red going into the COM is linking the two switches, and T&E going into L1 & L2 will be joined somewhere in the ceiling, rather than in the back box (and which is how I've previously seen it done).

I think I can disconnect the COM from both ends and that won't be connected to anything else, and then terminate the T&E on one socket and hide it behind a blanking plate and then use my standard switch on the remaining socket?

The reason for all this is that I've got a WiFi switch which doesn't require neutral, but doesn't support 2way switching.

Thanks
Paul

EFLImpudence · 3 Jan 2020

paulbristol said:
In each switch box, I've got two T&E however one of the T&E has the black wire snipped off. The red from this T&E goes into COM.
The black and red from the other goes into L1 & L2 on both switch boxes.

Ok.

In the ceiling rose, I only have a single T&E.

Are you sure?

Am I right in thinking that most likely the red going into the COM is linking the two switches, and T&E going into L1 & L2 will be joined somewhere in the ceiling, rather than in the back box (and which is how I've previously seen it done).

I wouldn't think so. Likely the L1s & L2s in both switches are the same cable.

It sounds like this arrangement - but obviously I can't be certain.

I think I can disconnect the COM from both ends and that won't be connected to anything else, and then terminate the T&E on one socket and hide it behind a blanking plate and then use my standard switch on the remaining socket?

I wouldn't think so.

You will need to do some testing to determine which wire is the supply Line(live) and where the other wires go and how the rose is connected to Neutral.

The reason for all this is that I've got a WiFi switch which doesn't require neutral, but doesn't support 2way switching.

Is it worth it?

paulbristol · 3 Jan 2020

Thanks. Yes that diagram makes more sense.

It's worth it because I work away a lot and want to be able to set timers and stuff like that and also I hate coming home to a dark house!

Would the best way to test this to be to turn off the power and short the t&e in one back box and see if I get continuity on the t&e in the other back box?

EFLImpudence · 3 Jan 2020

Yes, you could do that to be certain.
Also make sure that T&E is not connected to either of the two single reds.

If so, then one of the single reds must be the live supply and the other must be the switched live to the light.

Obviously I do not know which end is the live.

paulbristol · 3 Jan 2020

Thanks. I'll check. Wouldn't it be lovely if houses came with wiring diagrams!

EFLImpudence · 3 Jan 2020

Ah. That would be no fun.

I am a bit puzzled by the single cable at the ceiling rose.

Is that the only light in the hallway?

yorkspark · 3 Jan 2020

more than likely, they will also be an rb4 jointbox located under the floor.

paulbristol · 3 Jan 2020

Yes, it's the only light in the hallway. All the lights in the house seem to be like this. I guess it sort of makes life easier (changing lights wise) to have the circuit loop not in the rose but in this particular instance, the hallway is below a tiled floor in an ensuite which makes getting access essentially impossible.

AndyPRK · 3 Jan 2020

Octopus ?

paulbristol · 3 Jan 2020

I've just check the ceiling rose again. It's actually two T&E however one has the red snipped and one has the black snipped. So I've got a red from one T&E and a black from the other T&E going into the light fitting.

securespark · 3 Jan 2020

Obviously wired by a spark who loved using his side cutters!

securespark · 3 Jan 2020

paulbristol · 3 Jan 2020

Thanks for the drawing, that would make sense. I'll test it with a meter but to get rid of one of the switches, I'd simply choc block com and red together in one switch and then in the other switch leave com and put red into L1.

What would be the recommended best practice to deal with the unused remaining black wire which is running between the two switches?

securespark · 4 Jan 2020

Don't you need to know which common is live feed?

Sleeve any unused conductors as green/ yellow and connect to the earth terminal.

EFLImpudence · 4 Jan 2020

You could put a connector block on each end, or

put it in the terminal with the red at both ends, or

put it in the terminal with the CPC(earth wire) at both ends.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

2 way lightning

Similar threads