2 lights with a switch each, to 2 lights with 1 switch

[vemyr]

Hi,

I had a 3 gang unit which controlled 2 wall lights and the ceiling light. I've ripped it out and added 2 boxes. The ceiling is now on a dimmer switch.

The 2 wall lights were separately wired and so each could be turned on/off individually. I want to connect both of their switch wires to a single switch, but I'm not sure if this is dangerous.

Please give me advice or let me know if you need more information.

Thanks

 

[ericmark]

Using a double pole switch you can combine to one switch, but to combine with other methods you need to know how it is wired.

Wall lights are often taken from the ring using a fused connection unit and so there can not really be an answer until you know how wired.

 

[riveralt]

It does depend on how the switches have been wired.

If the wall light(s) switches have each been wired with a live and switch live then put both the lives into the Common Terminal (C or equivalent) and the two switch lives into the L (L1) terminal.

If the wall light switches have been wired with the live and neutral into the switch then you will need to either describe the old way it was wired or better still provide photographs.

 

[vemyr]

I believe the lights are on a radial circuit as the ceiling light only has a feed in and switch. I just tried attaching the two lives to COM and the two switch lives to L1 and both lights stayed on all the time. I don't think the range of switches I bought do a double pole switch.

Riveralt: The two wall lights each had a live and switch live going to the wall switch. It uses old colouring of wires, red/black.

 

[riveralt]

Riveralt: The two wall lights each had a live and switch live going to the wall switch. It uses old colouring of wires, red/black.

If you are sure of this then the light should work normally if you followed my instructions.
Is there a terminal block in the backbox with blue or black wires in it?

 

[vemyr]

Riveralt:

If I wire light 1 up as you describe, it works. If I wire light 2 up, also works. If I connect them both up to the one switch, they both remain on. This is how I wired it up just before you told me to as it seemed the most logical.

Here is a picture, I will be using matching wires when I have proved it works and will crimp/heat shrink them:

View media item 65363

 

[vemyr]

If I disconnect the switch completely, so it's the live wires connected and the switch live wires connected, the lights stay on.

 

[riveralt]

Riveralt:

If I wire light 1 up as you describe, it works. If I wire light 2 up, also works. If I connect them both up to the one switch, they both remain on. This is how I wired it up just before you told me to as it seemed the most logical.

Which perhaps suggests that one of your reds is a switch live and one of your blacks is a live.

Ideally you should do this with a tester but if one is not available then I would suggest that you first identify which way the switch goes - some have the word top on the inside.
Then wire the lights individually and see which way the rocker switch goes i.e. normal mode would be light on when on the switch is down.
If the light is off when the switch is down and on when the switch is up then you have live and switch live back to front. So mark the black with red tape.
Then you will have a red and black(red tape) in one terminal and red and black in the other.

 

[vemyr]

riveralt: Thank you for your help, it is working now.

 

[ban-all-sheds]

vemyr - doing electrical work when you don't actually understand it is a bad idea - far worse things can go wrong than a couple of lights on all the time. Trying different ways of wiring things hoping you get lucky is not a good strategy.

Please take some time to learn how things work, and get, at the very least, a multimeter before you dive in again.

• http://www.google.co.uk/search?q=electrical+circuits+101
  
  
• http://www.google.co.uk/search?q=multimeter+101
  
  
• http://kevinboone.net/electricity.html
  
  
• http://web.archive.org/web/20080213151445/http://www.kevinboone.com/domesticinstallations.html
  
  
• //www.diynot.com/wiki/electrics:books
  
  
• //www.diynot.com/wiki/electrics
  
  

 

[vemyr]

Hi ban-all-sheds,

I have a multimeter and will use it in future. I have just ordered one of the domestic electrical books on the wiki.

Thanks

 

[ban-all-sheds]

Good-oh.