Confused on two way switching - missing wires?

[biosbill]

Hello,

Recently had ceilings plastered and decorated....thus ceiling roses have been disconnected. Also, during the same works I moved the upstairs light switch and ran new cables, before re-plastering.

Now I'm trying to connect hallway lighting back together and I cant to the life of me remember how it was, it doesn't appear to match any of the 2 wire, or 3 wire diagrams online.

Downstairs switch currently has a twin and earth, plus a single red cable.

Upstairs I have the new switch (with 3 cores & earth chased up into the ceiling).

In the ceiling I have a twin and earth, plus a single BLACK cable. No ceiling rose, just a hole in the ceiling.

I am confused as to why the single cable appears to change colour? It appears to run down the wall towards where the downstairs switch is when I trace it back in the loft.

Could someone help advice where each wire should go? It almost doesnt feel like I've got enough wires - its not at all like the "loop-in" in all the other rooms. House was built around yr 2000 so not massively old, but old wiring colours.

Many thanks in advance,

William

 

[endecotp]

Do you have a multimeter?

 

[biosbill]

Yep. I work with automotive diagnostics and electronics all day but I'm a bit lost with household stuff!

 

[endecotp]

Use your meter to work out which wire is connected to what.

 

[Lectrician]

The single red downstairs is your live feed in COM. The strappers from L1 and L2 are contained inside the T+E. The single black upstairs is the neutral. The T+E is the other end of your strappers. You need to join the T+E to your 3 core, using the third core to return the COM from the upstairs switch. Use a joint box to the 3C+E, the existing T+E and a new short length of T+E to the pendant. BEWARE. If you have a different lighting circuit upstairs to downstairs, there is a good chance the neutral is borrowed.

Googled image:

 

[biosbill]

Perfect, that makes sense!

Many thanks,

William

 

[securespark]

When you moved the switch, how may and what type of wires were there feeding it and did they go up into the ceiling?