Ceiling-mounted KNX multi-sensor combining presence detection with brightness, humidity, temperature and sound sensing in one device. The humidity sensor supports threshold-with-hysteresis control of humidification/dehumidification equipment, and the sound sensor helps detect occupancy in areas not fully visible to the infrared sensor. Includes a rear connector with 3 digital inputs, one of which can drive a full 2-stage PI thermostat module via an NTC probe.