Changing two way light switch

[gerryb]

I’m changing a two way light switch in the hallway and want to be sure I’m doing it right.

the old one - pictured is labelled common and has a horizontal layout the new one, also pictured, is labelled L and has vertical layout

I’m assuming it’s a simple like for like with the two L1 and L2 wires

my question is really about the black common wire and the red common wire and if it makes any difference how I swap them to the two new L terminals

nb I’ll also be adding earth wire to the switch plate.


Would appreciate your help.

 

[ktuludays]

Yes, looks as you described

 

[terryplumb]

Your old switch doesn't have the "horizontal layout " that you think. It is exactly the same layout as the new one . Three terminals in a triangular format ,at each side.

 

[333rocky333]

You MUST keep the Red and Black with there relevant L1 and L2
As above the 3 cables are in TWO triangle formats (One is inverted) NOT in line as you suggest.
The new switch also has TWO triangle formats, however they are both same way up

 

[bernardgreen]

 

[gerryb]

That makes sense!
Thank you

 

[ericmark]

The Com/L is important must be correct, swapping L1 and L2 only swaps if up for on or down for on, it still works.

 

[gerryb]

Supplementary question

Top floor switch is the end of this circuit and controls pendant light in centre of room and the landing ligh in the hallway outside that room

Wire had become detached as I discovered when I removed the old switch plate

But there are only five wires not the six I would need to crest the inverted triangles illustrated above.

Both lights used to work so what configuration would make the new switch control both lights once more?

Thanks again in Advance

 

[EFLImpudence]

Please learn how switches work.
https://www.flameport.com/electric/lighting_circuits/lighting_switchtypes.cs4

 

[gerryb]

View attachment 240299

Please learn how switches work.
https://www.flameport.com/electric/lighting_circuits/lighting_switchtypes.cs4

That’s exactly why I’m here. So are you saying I should move the com to where I’ve got it in the left hand connection to the one you’ve marked on the right?

 

[EFLImpudence]

That’s exactly why I’m here. So are you saying I should move the com to where I’ve got it in the left hand connection to the one you’ve marked on the right?

No.

I have indicated that you should move the red wire as per the arrow.

 

[gerryb]

No.

I have indicated that you should move the red wire as per the arrow.

Got it. Thank you.

 

[gerryb]

So that’s given me power to the landing light but not the pendant in the room.

is there not an issue with having five wires not six?

and believe me I’m two months in trying to book an electrician to do this!

 

[EFLImpudence]

That should be the bedroom light switch.

Can we have another picture showing both the switch connections AND the cables coming out of the wall?

 

[gerryb]

I’ve attached one with the right hand wires update as per the earlier advice. As you can see there are five wires, not six