varilight 2 way dimmer switch

[fishman]

Hi there,

I've just bought a Varilight master dimmer and a slave. I have a two way light switch set up in my living room. However, I can't make head nor tail of the wiring set up in this room and how it relates to the varilight instructions, or to previous posts on this forum.

My current set up is as follows:

At one switch ( which I think is the master) there are two cables entering the box. One cable has 2 red wires which are connected to the Common connector on the switch plate. There are then two balck wires which are connected to the black wire of the second cable.

The second cable has the above-mentioned black wire, with a yellow wire connected to a connector marked "1 way" on the switch, ,and a blue wire connected to "2 way"
There are also 2 red wires that do not go anywhere (isolated).

Then, at the second switch across the room (which is the slave?) there is a red wire that goes to Common, a blue wire that goes to "1 Way" and a yellow wire going to "2 way"

Earths are all present and correct.

First question: what has happened to the black wire?
Second question: the blue and yellow seem to be switched around from the "1way/2way" connections - relevant?

Third question - how does this related to the wiring diagram for the Varilight dimmers?
The instructions are available
here

Any help appreciated.

 

[breezer]

url you gave is wrong, find correct one and press edit button on your post

 

[fishman]

oops... I've now edited the original post and it should be there for all...

 

[ban-all-sheds]

..At one switch ( which I think is the master) there are two cables entering the box. One cable has 2 red wires which are connected to the Common connector on the switch plate. There are then two balck wires which are connected to the black wire of the second cable.

The second cable has the above-mentioned black wire, with a yellow wire connected to a connector marked "1 way" on the switch, ,and a blue wire connected to "2 way"
There are also 2 red wires that do not go anywhere (isolated).

Please don't take this the wrong way, but are you sure about this?

As I see it you've described a cable with 2 red cores, a cable with black, yellow & blue cores, and 2 single black wires and 2 single red wires.

How many lights are controlled by the two way switches - is it 2 by any chance?

Then, at the second switch across the room (which is the slave?) there is a red wire that goes to Common, a blue wire that goes to "1 Way" and a yellow wire going to "2 way"

Now that end sounds quite normal - see the bottom switch of the pair in the two-way switching circuit in this diagram:

First question: what has happened to the black wire?

Could you have a good look at the black wire that is part of the 3-core + earth cable at the "master" end to see if it is actually a red wire with black sleeving added?

Second question: the blue and yellow seem to be switched around from the "1way/2way" connections - relevant?

Only if you are anal about the lights only being on if the switches are symmetrical (i.e. both down or both up)

Third question - how does this related to the wiring diagram for the Varilight dimmers?

Once your existing connection topography is clear, this will also be clear.

Hopefully....

 

[fishman]

Hi Ban-all-sheds. Thanks for quick reply. Yes I'm sure about the set-up of the wiring. Now I'm no electrician, but from reading around my Collins DIY Manual and reading relevant parts of this forum, it appears that the wiring does not conform to the 'usual' set-ups - hence my Forum post.

My house is only 8 years old, so I thought it should be a simple task - but no!
In answer to your question, my switches do control two lights.

Any ideas/suggestions welcomed. If not, next stop, a call to the electrician!!! £££££...!

In addition, the Varilight dimmers have 3 connections - Live, S and arrow symbol (Load). How does this relate to my wiring - specifically which is Load and which is S connection? I presume that the red wires to my existing Common terminals connect to the Live on the dimmer switches?

Many thanks.

 

[journeyman]

Your lights have been wired by sending the loop into the switch box. Both neutral and live are present at the switch box. That is why there are two lives connected to the common. The load is most likely connected to the other switch.

You can use the first wiring diagram to wire up your dimmers.

You will have to correctly identify your cables. I think that you have three cables connect to the first switch.

Identify the cables and I can probably work out which way to wire.

I think that you have two twin and earths and one 3 core and earth connected to the first switch.

 

[ban-all-sheds]

I think that you have two twin and earths and one 3 core and earth connected to the first switch.

Ignoring earths, that's 7 conductors. The initial post identified 9 conductors.

At one switch ( which I think is the master) there are two cables entering the box. One cable has 2 red wires which are connected to the Common connector on the switch plate. There are then two balck wires which are connected to the black wire of the second cable.

The second cable has the above-mentioned black wire, with a yellow wire connected to a connector marked "1 way" on the switch, ,and a blue wire connected to "2 way"
There are also 2 red wires that do not go anywhere (isolated).

Fishman is also adamant that he has a 3C+E cable with black, yellow & blue cores at one end and red, yellow, and blue cores at the other end.

I may not be a qualified electrician, but I've never heard of such cables. Given that fishman assures us that that is what he has, then I suggest that there is a Black/Yellow/Blue cable at one switch, going who-knows-where, and a Red/Yellow/Blue cable at the other switch, also going who-knows-where.

 

[journeyman]

Ban, you are right.

Adding up the coulours gives 3 two core and earth plus one 3 core and earth.

3x2+3=9

 

[ban-all-sheds]

Seems like an awful lot to me.

And there is still the unresolved issue of the 3C/E cable.

Fishman - do you have a multimeter?

 

[journeyman]

At the first switch.

Connect the two red wires that are in the Common to Live.

Connect the yellow wire to S

Connect the blue wire to ~/

At the second switch

Connect the Red wire to Live

Connect the Yellow wire to S

Connect the Blue wire to ~/

The two red wires that are connected together will have to be separated.

One of them belongs to to the yellow and blue wire. It must be connected to Live.

The other goes to the lamp. It is part of a twin and earth wire. It must be connectd to ~/

This is a best guess based on what you have described. It may not work and it could damage your switches or blow a fuse.

Check you cables in the first switch. There should be four. N
ot two.

 

[ban-all-sheds]

This is a best guess based on what you have described. It may not work and it could damage your switches or blow a fuse.

Perhaps unwise to be guessing at this stage, then?

 

[journeyman]

It is not just a guess. It is based on the number of wires described and the way this kind of wiring scheme should work. The number of wires suggests four cables. Two loop cables. One cable to the load and one 3 core and earth. It is easy to work out which cables are the loop cables and which is the three core and earth. The two red wires connected together, but not connected to the switch will be the feed to the lamp and the return from the other switch. The circuit is a loop in ceiling rose done in the switch cavity and not in the rose. I have seen them before. If it is not this scheme then my method will not work. If it is this scheme then my method should work.

 

[fishman]

Thanks for the responses. I haven't got a multimeter, but I will try to borrow one - this will then confirm what the wires are used for and I'll try Journeyman's suggestion.

Cheers