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JamesI
JamesI, Developer
Category: Home Improvement
Satisfied Customers: 1459
Experience:  I have a portfolio of renovated houses, including DIY projects from installing bathrooms and new heating systems to rewiring.
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I would like to change a single light switch to a double

Customer Question

I would like to change a single light switch to a double light switch, to control two separate lights. There is a single feed with two sets of three wires from each light coming into the rear of the box, 2 Coms at the top of the switches with an L1 and L2 at the base of each switch. Please could you tell me in simple English which wires go where when installing thanks in anticipation Stuart
Submitted: 10 months ago.
Category: Home Improvement
Expert:  JamesI replied 10 months ago.

Hi Stuart,

My name is ***** ***** I will assist with your query this morning.

Expert:  JamesI replied 10 months ago.

Firstly the lights your looking to wire, can they only be controlled by one switch or is there another switch (eg at the other end of the room).
Secondly the three wires in each cable, what are their colours (eg. Red, Black,Yellow\Green or Blue, Brown, Yellow\Green)

Finally when you took off the single pole switch were all the cables terminated in the switch or were all the Blue or Blacks terminated in a terminal block lose within the back box?

Once I have this info I can give you further assistance.

Customer: replied 10 months ago.
The lights will only be controlled by this switch no other switches. The original wires in the box when I took off the cover were a red in the top Coms a black out at the bottom L1 and finally an earth to the metal casing. The wires I want to add are brown blue and the earth
Expert:  JamesI replied 10 months ago.

Ok, the wiring you have for your switch is a switched live, so you dont have a neutral in the switch to use for your second light. As such to get the second light to work you have two options.

1. You run a third cable into the switch to power this second light, which comes off the lighting circuit.

2. You have a cable from the lighting circuit delivered in the ceiling rose for the new light.

Assuming you have already gone with option 2, which is how the existing light is wired, you wire earth of the new cable to the terminal block at the back which is part of the back box (and where the existing cable earth should have been terminated), in terms of the other two cables it doesnt really matter what way round they go, providing one goes in L1 or L2, and the other goes in common. Traditionally Blue is equivalent to Black and Brown to Red, however since this is a switched live and not traditional live and and neutral it doesnt make any odds.

Please let me know if you need any further assistance.

James

Customer: replied 10 months ago.
Thanks for your help in a nutshell wire new earth to existing earth on back of box, brown to Coms and blue to L1
Expert:  JamesI replied 10 months ago.

That should work, the only change you may need to make (after you test it with the power on) is if the switch is in the wrong position when the light is off, you may need to move the blue to L2.

Regards

James

Expert:  JamesI replied 10 months ago.

Hi Stuart, I havent heard back from you, if you have everything you need, please rate the service received using the star rating, so I can close the case.

Should you need any further assistance please advise how I can assist you further.

Regards

James

Expert:  JamesI replied 10 months ago.

Hi Stuart, so I can close the case please login and rate the service received using the star rating on the Just Answer page, should you need further assistance please let me know.

Thanks

James

Expert:  JamesI replied 9 months ago.
Hi Stuart, so I can close the case please login and rate the service received using the star rating on the Just Answer page, should you need further assistance please let me know. Thanks James
Expert:  JamesI replied 9 months ago.

Hi Stuart, so I can close the case please login and rate the service received using the star rating on the Just Answer page, should you need further assistance please let me know.

Thanks

James

Expert:  JamesI replied 9 months ago.

Hi Stuart, so I can close the case please login and rate the service received using the star rating on the Just Answer page, should you need further assistance please let me know.

Thanks

James