The DALI-2 PIR CLS LARGE AREA SENSOR sensor detects motion and presence. It features an exceptionally large detection area - the diameter of the motion detection area ranges from 19 meters when mounted at a height of 2 meters to 24 meters when installed at a height of 4 meters. For presence detection, the coverage area is 4 meters at a mounting height of 2 meters and 5 meters at a height of 4 meters. For surface ceiling mounting please see under accessories.