New Dimmer switch - Help needed

[Homeowner200]

Hi ,
I moved into our new home and shortly after the dimmer switch in the living room broke. I thought at first ist should be an easy switch. But it’s now more confusing than ever. The old dimmer ( metal face ) has three wires red , yellow and blue . Two wires blue &yellow going into one port and the red one in the other. There is no earth wire in the socket .
Could it be possible that the earth wire is with the blue wire in one of the ports ?

I will attach two pictures so you can see what I am talking about.

Old dimmer :



New dimmer :



Could you please help to figure out which wire goes where?

Thank you so much for your help.

Cheers

The new homeowner.

 

[333rocky333]

The Earth should have been in the empty terminal connected to the metal.
Swopping that dimmer is a very basic task, no disrespect, for safetys sake you should really do a bit of research before attempting tasks like this

Post a pic of the wires in the wall box

 

[Homeowner200]

For me it is very confusing why two wires go into one port and I haven’t any solution why. I have to say that I am not familiar with UK wires as in Germany things look bit different .

I thought as well that a switch of a dimmer should be straight forward, but I was wrong .

 

[333rocky333]

In the UK its common for that cable to be used in a 2 way circuit, with the yellow and blue known as the STRAPPER cables, is it possible there may have been a second switch.

Its possible the previous owner wanted dimmer and not 2 way, so as the easiest option joined the 2 strappers together. therefore the Red is the live input

There could be other options

The yellow and blue could be 2 switch line outputs serving 2 seperate lights at sometime, therefore the Red is the live input

Lastly

The yellow and blue could be a supply in and a supply out, with the Red as the switch line output, but id say extremely unlikely.

In the UK Metal switches must be Earthed using the terminal attached to the metal, this is green and yellow cable or sleeved usually, its likely already in the wall box and will need a short link to the faceplate.

As for your new switch its a 2 way switch but can be used in your case as 1 way,
The instructions will show the 3 terminals L1 and L2 and The squiggly line symbol is the Variable Output

 

[333rocky333]

I thought as well that a switch of a dimmer should be straight forward, but I was wrong .

Actually you did RIGHT to question it, too many people come here after they have pulled things about and poked wires into different holes hoping it to work.
When you understand circuits and complete the task you will realise how easy it can be and be more confident doing other DIY work

 

[winston1]

So put the red wire into the squiggly terminal and the blue and yellow both into L1. If it turns on max at initial rotation move both blue and yellow to L2. In other words wire it as the old one was.

 

[ban-all-sheds]

I have to say that I am not familiar with UK wires as in Germany things look bit different .

Even in Germany, putting an earth conductor into a switch terminal will not end well.

 

[Homeowner200]

Managed to fix the dimmer switch. I found the earth wire and the red wire had to go into the squiggly line port the blue one into L1 and the yellow one has to been capped.

Glad it’s sorted .

 

[Iggifer]

I hope you don’t mean you put the earth and the the red into the same terminal! Cos that’s what it sounds like you’ve done

 

[ban-all-sheds]

It would be very worrying indeed, and indicative of some very urgent investigation required, if that is what he did.

Think about it.

 

[Iggifer]

It would be very worrying indeed, and indicative of some very urgent investigation required, if that is what he did.

Think about it.

Obviously it would cause a big bang if the bare copper was connected to an earth path, but there are lots of installations, particularly those with no cpc on the lighting circuit or conduit as the cpc that have switch drops/strappers in twin/3c+e that don't have a full path because some joey has come along and bodged it.

We can only go on what the OP has written, and he has quite clearly said the "earth wire and the red wire had to go into the squiggly line port"

 

[ban-all-sheds]

Obviously it would cause a big bang if the bare copper was connected to an earth path,

Indeed.

And there hasn't been a big bang.

So if the bare conductor was connected to a terminal, clearly it cannot be a functioning earth.

Hence "It would be very worrying indeed, and indicative of some very urgent investigation required, if that is what he did."

 

[Iggifer]

Oh I thought your 'think about it' comment meant he was very unlikely to have connected earth to live - maybe it did.

If the OP comes back, I guess we'll find out. Perhaps he means he connected the earth to this 'squiggly line'

 

[ban-all-sheds]

No, it meant what it said - if he really has connected the 'cpc' to line there's some urgent investigation needed.

 

[Homeowner200]

Hi ,

I can tell that there hasn’t been a Big Bang. Everything is working fine . The dimmer plate is earthed .
The red wire is in the right port and the blue wire is in the L1 port .
The yellow one is not in use and was capped .
Met one of our neighbors in the street who is an electrician and he came around and checked it. All good .

Thank you for your assistance.