The Homematic IP presence detector is part of the Homematic IP smart home system and reliably detects the slightest movements indoors. If the presence detector is mounted on the ceiling, it registers even the smallest movements, such as typing on a keyboard, within a radius of up to 3.5 m and a detection angle of approx. 105°. Larger movements are detected within a radius of up to 7 m. In addition, the integrated twilight sensor also detects changes in brightness. This means that the lighting can be switched on automatically when motion is detected. The presence detector is also suitable as a sensitive sensor for alarm detection. To ensure that the detection sensitivity is maintained even at high room temperatures, the sensor automatically adapts to the respective conditions. The small detector is mounted on the ceiling using screws, which are supplied with matching dowels. A built-in tamper contact reliably prevents unwanted changes to the presence detector after installation by issuing a message via the Homematic IP app as soon as the sensor unit is removed. Two AA batteries are used for the power supply, which supply the presence detector with energy for up to two years.