2 way landing light switch wiring problem

[kpfran]

hi,i am wanting to replace a Greenbrook T40 timer switch on the landing with a new standard 2 way light switch.
My wiring is pre 2004.
The Greenbrook timer switch presently has three connections,one at the top labelled Load and two at the bottom labelled 2 way and Live.
The top load connection has both a black and yellow wire going into it.The two bottom connections both have single red wires going into them.There is also a blue wire in both the switch boxes at the bottom and top of the stairs that is disconnected.
i tried putting the black and yellow feeds together in the top Comm connection of the new two way switch and the two red wires in the bottom L1 and L2.The result being that only the top landing light switch will turn the light on/off.The switch at the bottom of the stairs will not work.
All suggestions greatly recieved.

 

[Murdoch]

Did the timer control both lights?

 

[kpfran]

there is only one light on the landing,with a switch at the bottom of the stairs and the timer switch on the landing ,both controlling the single light bulb.

 

[Murdoch]

What colours do you have at the downstairs light switch ?

 

[SPECIAL LOCATION]

Cable colours in this situation mean very little at all..
There are multiple ways to wire up two-way switching..

you will need a permanent live feed coming in.
switched live strapper wires between the switches
and a switched live out to the load (light).

The live in & out may be at the same switch with three strappers.
or live in & out at different switches with two strappers.

Would guess your live in & out are the Red & Black of a T&E cable

Your strappers were Red / Yellow / Blue of a 3core&E cable
but for some reason blue needed as a strapper has been disconnected in the past..???

Easiest and safest way is to use a continuity tester/meter with the power turned off to identify which wires are which between the switches.

Otherwise it's a bit of guess work as to which colours were originally used.

 

[kpfran]

single yellow in L1 and single red in L2..... blue not in use { left hand connections in photo are the downstairs switch for the upstairs light.}

 

[kpfran]

this is how the upstairs is wired at present.Black and yellow to top Comm and the two single red wires to 1 way and 2 way

 

[kpfran]

this was the original timer switch that im trying to replace...the black and yellow wires were connected to the top Load connector and the two single red wires were connected one to the bottom left 2 way and the other to the right Live connector.

 

[Murdoch]

So at a guess:

both reds to L1, blue and black to l2, yellow to top connection

It may go bang!

AND obviously switch the lighting circuits OFF before you touch it

 

[Sharpend]

To be clear that that Murdo has told you is for top (timer) switch, at the Double switch follow the red yellow blue as per Murdo for com l1 l2

 

[kpfran]

So at a guess:

both reds to L1, blue and black to l2, yellow to top connection

It may go bang!

AND obviously switch the lighting circuits OFF before you touch it

Thanks for all your help Murdoch,that has done the trick....all working fine now,thank you.

 

[kpfran]

To be clear that that Murdo has told you is for top (timer) switch, at the Double switch follow the red yellow blue as per Murdo for com l1 l2

Thanks for the extra bit about the bottom double switch....all connected and working fine now.Thank you.

 

[Murdoch]

Thanks for all your help Murdoch,that has done the trick....all working fine now,thank you.

thank YOU for giving us an update. Courtesy costs nothing, but is so appreciated

 

[ProDave]

How can it work "fine"? the top timer switch is only a 1 way switch so how are you getting proper working 2 way up and down switching working?

 

[kpfran]

Hi Dave,
The original circuit before the timer was installed was a conventional 2 way system, with a light on the landing being controlled by a 2 way switch at both the bottom and top of the stairs.
As I didn't fit the timer switch myself ( not being an electrician ) I can't help with your query.However with the timer installation the system still worked as 2 way.There was also a timer switch fitted in the master bedroom at the same time and this also worked as a 2 way,the timer switch being by the bedroom door and the 2 way above the bed.
The only time the timer switches stopped working as 2 way was when I replaced bulbs with these modern low energy light bulbs.
This is why I have had to replace the timer switches back to a conventional 2 way light switch.
As I say I'm no electrician hence why I came on here looking for help.
I can only assume that the blue wires were disconnected when the timer's were fitted and by reconnecting them as advised in the new conventional 2 way switches everything is now working as it should,both with the landing light and in the bedroom.
Thanks to the two gentlemen for their advice and sorting out my problem.
Hopefully they might be able to answer your question.