Hi Geurt
Thanks for the helpful advice. I tend to work cautiously, so even though I think I have it figured out, I would like your opinion on it. First of all, here is the drawing I made of the current situation with some pictures I took to double check.
I noticed that on the first sketch, I switched the brown and the black wire, so it is 1’ & 2’ that are connected through the brown wire and 1 & 2 through the black one, but fundamentally that doesn’t change the situation: indeed the wires do not have the right colours. “They”, being the previous owners, who renovated the electricity in this house used an electrical wire with 5 colours in it to connect the switches (see blue arrow): there is a grey wire that is not used, the blue wire and the grounding wire wire simply connected through and the brown and black wires were used to set up a system, which IS, I think, the classic multiway switching system. I grabbed the wikipedia picture you mentioned in your reply and measured every possible situation:
… and this is what came out: every red wire in every situation was indeed ‘hot’ and every black wire in every situation was not. UP & DOWN indicate the position of the switch. It was the left switch that was in full control of whether 1 or 1’ was hot on the other switch, so I think this wiring is exactly what is happening in my house. I guess this also means that I can proceed with connecting the brown wires (which indeed makes the colour of the wiring correct) and then use black wiring after the fibaro switches.
Thanks again for the support!
Roel
