Also, if I take the colours on the supplying cable literally, doesn't this mean my light has been running through earth (unsheathed) and neutral (black)? Would this still light? I thought it wouldn't as isn't neutral at approx ground voltage whereas live cycles from -230 to +230 V?
Time to...
Ok, so I'm changing a metal ceiling rose in my flat with a similiar unit and have come across something weird/dodgy.
When I disconnected the cabling I found a 3 core cable (black, red and one unsheathed). Black was connected to live, unsheathed was connected to neutral and red connected to...