I've replaced the ceiling light fitting - something I've done a few times before - and it works fine. Unfortunately, the lights in two other rooms now don't work - presumably in the same loop as the one I changed.
Could it be that I connected the three black wires in the wrong combination? I'm pretty sure I connected them as before - two to one side and on to the other. but what if I got them mixed up? Is this what would happen? Is it a bad idea to try them in a different combination?
btw the other two rooms have sets of spotlights with their own transformers.