Security light sensor wiring

[joeberg]

Hi Everyone

Long time no visit but I need help again. Im trying to fit a motion sensor for my mother an ELRO ES 90 to the Garage the existing feed is 4 wires Red Blue Yellow and Earth This has confused me a bit and having blown one sensor I thought better to check with the experts this time Earth to earth I presume I would also assume blus is neutral but which is live and I assume the other is switched If red is Live I would have assumed neutral to be black not blue

recap
sensor has 4 ports with brown blue and eath
Feed has 4 wires Blue red Yellow and Earth which goes where

Thanks

Joe

 

[Taylortwocities]

Do not "assume" anything.
All that you can be certain of is that a blue wire is blue, a black wire is black.

You need a test meter to be certain as to which wire does what.
Alternatively if you have access to the other end of the cable:
Is it in a switch? Can you post a photo of the connections?