KNX Functions: Device Comparison
21 KNX function categories: find the right actuator, sensor or logic module for your project. Sorted by price per channel.
KNX Switch Actuator
A KNX switch actuator switches loads (lights, sockets, heating pumps) on and off. Each channel is an independently switchable output. For dimmable lights, use a dimming actuator.
KNX Dimming Actuator
A KNX dimming actuator controls light brightness continuously (0–100 %). Each channel can independently dim one lighting circuit. Universal dimmers work with LED, halogen, and low-voltage luminaires.
KNX Blind Actuator
A KNX blind actuator raises and lowers shutters, venetian blinds, and awnings. With slat control, the tilt angle can also be adjusted. Each channel controls one motor independently.
KNX Heating Actuator
A KNX heating actuator drives electrothermal valve actuators (0–100 %) for radiator valves and underfloor heating circuits. Each channel controls one room or one heating loop.
KNX Binary Input & Push Button Interface
A KNX binary input (push button interface) connects volt-free contacts like buttons, switches, or window contacts to the KNX bus. Each input sends a telegram to the bus when activated.
KNX Presence Detector & Motion Sensor
A KNX presence detector senses whether people are in the room and automatically controls lighting, heating, or shading. Motion detectors only respond to movement; presence detectors also maintain output when people are stationary.
KNX Weather Station
A KNX weather station measures wind, rain, brightness, and outdoor temperature and sends the values to the bus. Blinds retract automatically in storms; shading responds to solar irradiance.
KNX Room Sensor & Multi-Sensor
A KNX room sensor measures multiple room parameters simultaneously: temperature, humidity, CO₂, brightness, and presence. Ideal for ventilation control, comfort regulation, and IAQ monitoring in offices and living spaces.
KNX Tunable White
A KNX tunable white actuator simultaneously controls brightness (0–100 %) and colour temperature (warm to cool, 2700–6500 K). Ideal for workrooms, offices and living areas. Light adapts to the time of day without needing separate scenes.
KNX Cooling Actuator
A KNX cooling actuator drives electrothermal valve actuators on chilled ceilings or fan-coil units. The valve opens proportionally (0–100 %), identical technology to the heating actuator, just with the opposite effect. Many actuators handle both heating and cooling on the same channel.
KNX Window Contact & Door Contact
A KNX window-contact interface connects conventional reed switches (windows, doors, skylights) to the KNX bus. Each input sends a 1-bit telegram on state change, and automation can then reduce heating, retract blinds or trigger an alert.
KNX Smoke Detector Interface
A KNX smoke detector interface receives the volt-free alarm contact of a standard smoke detector and converts it to a KNX telegram (DPT 1.005). This lets KNX automatically unlock doors, switch off ventilation or turn on all lights when an alarm triggers.
KNX Temperature Sensor
A KNX temperature sensor measures room temperature and sends it as a floating-point value (DPT 9.001) to the bus. Heating controllers, air conditioning units and switching actuators use this value for regulation, and a single sensor can supply multiple devices simultaneously.
KNX Humidity Sensor
A KNX humidity sensor measures relative air humidity (DPT 9.007, 0–100 %) and sends the value to the bus. Ventilation controls and air-conditioning systems can respond automatically, since air that is too humid raises the risk of mould, while air that is too dry irritates mucous membranes.
KNX Motion Detector
A KNX motion detector senses movement within its detection area and sends a 1-bit telegram (DPT 1.002) to the bus. Unlike a presence detector, it reacts to rapid movements, ideal for corridors, stairwells and outdoor areas where short switching times are desired.
KNX Brightness Sensor
A KNX brightness sensor measures illuminance in lux (DPT 9.004) and sends the value to the bus. Blind controllers automatically lower roller shutters in sunlight, constant-light controllers maintain a steady light level in offices, regardless of daylight levels.
KNX Scene Controller & Scene Actuator
A KNX scene controller stores and recalls scenes (DPT 18.001): with a single button press, multiple devices switch simultaneously to predefined states. Typical: the "movie night" scene dims the lights, lowers the blinds halfway and switches on the sofa light.
KNX RGB Dimming Actuator
A KNX RGB dimming actuator controls the three colour channels red, green and blue separately or as a combined RGB object (DPT 232.600). This allows LED strips and RGBW luminaires to run in any colour, via ETS scenes or direct colour selection via push-button.
KNX Ventilation Controller & Fan-Coil Actuator
A KNX ventilation controller regulates the speed of fan-coil blowers (DPT 5.001, 0–100 %) and integrates heating and cooling valves in one unit. Typical in offices and hotels: heating, cooling and ventilation via a single actuator with KNX connectivity.
KNX Energy Monitoring & Power Measurement
A KNX energy meter measures active power in watts (DPT 14.056) and sends the value periodically to the bus. Consumers such as heating, air conditioning or lighting can be monitored: detect load peaks, break down energy costs, uncover savings potential.
KNX Logic Module & Timer
A KNX logic module combines bus telegrams with AND, OR, and NOT operations, without custom ETS application programming. Timer channels switch devices at fixed times or according to weekly schedules.
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