KNX presence detector, multi-channel for 2-zone constant light control. Multi-channel presence detector with integrated bus coupler and 2 independent zone detections for ceiling installation for brightness and motion-dependent switching. The lighting control of zone 2 is proportional to zone 1. A parameter enables the selection of a proportionality coefficient. The presence detector also enables the KNX dimmer or the KNX/Dali interfaces to be controlled via an object for further lighting regulation. The sensor has a semi-automatic and an automatic operating mode. Basic settings can be made directly on the already installed device without dismantling or the output can be switched on/off optionally via a remote control. The switch-off delay can be freely selected. Functions: lighting ON/OFF, forced control, dimming value, dimming value when present and absent, time functions, scene, scene when present and absent, master/slave function. Reflection rate of the natural and artificial light value can be set via parameters. The device can be programmed via KNX ETS or KNX easy.