old lighting circuit conundrum

[chemist]

I am trying to add an outdoor (PIR) light to an existing old two way switching circuit. The outdoor light will be permanately switched on.

Excluding the earths, At the far end of the hall 2 way switch, There is a red live wire from one cable and both a red and black from another cable.

At the door switch ( where I am connecting the outdoor light), there is There is a red wire from one cable (not live) and both a red and black from another cable. By multimeter the dual red/black wires between switches show continuity.

I have replaced the 1 gang 2way switch at the door with 2 gang 2 way switches. The light circuit works, i.e. I can turn on the light from either switch, but I cannot get the outdoorlight to work and by multimeter there appears to be no live at this switch.

How should they be all connected?

Any ideas welcomed

 

[plugwash]

it sounds like you don't have either a permanent live or a neutral at that point, you will have to find a permanent live and neutral from the lighting circuit and bring them down to the switch, this will most likely require lifting floorboards in the room above and chasing out the wall down to the switch.

 

[Space cat]

I'm afraid that plugwash is correct. You have the old style two way light circuit. The red wire on its own, which will be in COM on the switch, is switched live for your indoor light. Of the other two, one will always be live but exactly which one depends upon the position of the other switch.

No fixed live, no neutral at all, no chance.

 

[securespark]

What have you connected the LNE from the new fitting to, exactly?

 

[chemist]

Many thanks for the prompt and helpful replies.

You have saved me hours of messing around trying to make it work.

Pity, I never found this site before starting the project

Can't wait to tell the wife - Oh well, back to the sofa with a brew!