are you wiring the fan?, if so it is usually connected:
red: live
yellow: switched live (sleeved red)
blue: neutral.
if existing wiring you need to get it checked out.
sorry did not read properly :oops:
i was thinking that there was a switch and you wanted to know how to overide.
if there is no switch, (and you cant fit one), the only possibility is to connect perm main and have the light on sensor.
you can connect it like that, it doesn't really matter which way round the wires go but it is normal practice to connect live cables to com and s/l to L1.
don't forget to connect earth to faceplate if metal.
p.s. have you checked the rating of the dimmer.
hi high!
what are the three terminals LNE?
it may be that a perm main is not required and the overide is done by flicking the switch on-off-on. should be stated in the instructions.