REAL PRESENCE SENSOR
REAL PRESENCE SENSOR is a compact presence sensor. It is intended for installation in a ceiling.
The difference between the motion sensor and the presence sensor is that the second type of sensor will not allow the lights in the room to go out while there are people present. This makes them ideal for installation in rooms where there is a constant presence. With motion sensors, the lights turn off and on again even if there is movement.
The signal can easily pass through wood, plasterboard, glass, and thinner walls.