There are 2 types of trailing cables , numbered and coloured. If you open carriage you can look at the pcb to see what numbers are live , neutral and earth these are positioned at the bottom right. The remaining 2 are top left and are call box up and down. If you are not fitting call boxes don't worry about those . If you are fitting call boxes then it is a little bit more complicated. The live from the mains gets rooted through call box on/off switches then down trailing cable.
JohnoMumbles, December 2012
