More
information and diagrams below:

Step
by step instructions on Changing a one gang
two way light switch.
This is the most commonly used switch on
the bottom and top of stairs. Two way switches
can appear difficult at first but if you
take your time and study the pictures/diagram
below, it should be pretty straight forward.
You will need a 2way light switch for this,
they can be identified by looking at the
terminals on the back of the switch.
E.g. com (common) L1 terminal and L2 terminal.
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One
Way Switch |
Two Way Switch |
6
Diagrams - Click
on the desired colours and difficulty to
show diagram
Brown sleeving
or tape would of been placed on the wires
as shown to show the blue is live.
“There
are other methods of wiring a two gang two
way switch but this is the most common way
and is the easiest by far”
- Jamie Vernon of Online
Electrical Services LTD.
How to convert a 1 gang
1 way (single switch) to a 1 gang 2 way
switch system?
For 1 gang two way switching
you will need 3 core and earth cable to
reach from your new intended light switch
to your old existing light switch via the
easiest route. Click
here for permitted cable routes.
Once you have run the
3core + earth cables from A to B you will
need to place it in the appropriate system.
Click
here for different back boxes and containment.
Below
there is 3 pictures listed per stage. The
reason being there is different cable colours
and this is to be sure that your colour
is listed here! (Only one of the pictures
per stage will apply for you).
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NEW
COLOURS
If your existing
light switch cables look like
this follow the top pictures.

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OLD
COLOURS
AND
EXISTING
OLD COLOURS TO NEW 3 CORE CABLE
If your existing light switch
cables look like this follow
the bottom pictures.

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NEW
COLOURS
Add the 3
core and earth as shown in this
picture.
All the wires
should have brown sleeve/tape
on them, I have left some off
so you can see the colours.

|

 |
OLD
COLOURS
Add the 3
core and earth as shown in this
picture.
All the wires
should have red sleeve/tape
on them, I have left some off
so you can see the colours.

|

|
Existing
old colours to new 3 core cable
Add the 3
core and earth as shown in this
picture.
All the wires
should have brown sleeve/tape
on them, I have left some off
so you can see the colours.

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NEW
COLOURS
AND
EXISTING
OLD COLOURS TO NEW 3 CORE CABLE
Connect the 3 core + earth
cables as shown in this picture.
The wires on this switch should
copy/mirror the other switch.

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OLD
COLOURS
Connect the 3 core + earth
cables as shown in this picture.
The wires on this switch should
copy/mirror the other switch.

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