change 2way swith to 3 way switch add outside light power

[helpdave]

Hi All
Can anyone help me , i have switch in hall way for upstairs light and hall light , i want to change this to 3 way socket to power outside light.

1. switch one hall light
2. swith two for upstairs light
3. swith three for outside light

Problem is how to power switch 3 . Looks like witch 1 and 3 are switch live ........... I'm not sure how to get live feed to power outside lamp ? Please help

 

[2891]

Hi.

The problem you have at the moment is that all cables to switches are live feed, with no neutral. so you will need to get a neutral down to the switch to act as a path for the return current.

If your existing switch has been wired correctly, all cables should have brown sleeving or tape on to show they are live feed.


The easiest way to do it is run another cable from the lighting circuit loop. (junction Box)
one cable becomes switch live. run the cable (brown conductor) to light. return cable becomes neutral (Join in light switch with connector block neutral return)

 

[helpdave]

Hi

Thanks for quick reply . Looks like site is very popular.

Original switch downstairs was wired like so

switch one : black @ L1 . Red @ com and Red going from com swith 1 to com switch 2

switch 2 : Red @ com and red/black @ L1 . L2 red

I want to change switch 3 switch type and problem is how to get power to 3rd switch to power outside light

 

[MANDATE]

If I understand your problem correctly, you want to change a gang of two switches to a gang of three switches to operate three separate lights.
feeding power to the third switch is simple. Just like the second switch, a short wire from 'com' of SW1 to 'com' on SW2 feeds power to both, so all you need is another short wire from 'com' on either SW1 or SW2 to 'com' on SW3.
Thats the easy bit. The next bit of the problem is to get the 'switched live' wire from L1 to your outside light, but the biggest problem is the 'neutral'.
Switches don't need neutrals so are not usually provided at the switch.
Your options are to run the neutral wire to where there is a neutral, or provide a neutral behind the switch as advised by 2891.

 

[saxondale]

I hope all thats put you off