Tech Logic VoiceLink II User Manual page 16

Push an awl or similar pointed round rod through tile (for screw holes)
Place the two long screws (3X25mm) through bracket and tile
Screw into sensor holes and tighten snug
Route the sensor cable to its exit location near the receiver
Reinstall the ceiling tile.
IR Sensor Installation (Wall Mount)
Locate the center of the long sidewall or the center of hard ceiling
Bend bracket at the scoured bend grooves
Mount bent bracket onto sensor using the short sheet metal screws
Hold sensor / bracket in place on the wall or ceiling and mark mounting
holes
Drill hole for installing appropriate mounting hardware
Plug sensor cable into sensor
Install sensor
Route sensor cable to receiver in a tidy manner