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KNX Interface, 8 binary and 2 sensor inputs

The Interface KNX B8-TH has eight binary inputs and two additional sensor inputs for temperature or temperature and air humidity. They are used to integrate signals and values from conventional buttons and sensors into the KNX building bus.
The application software of the Interface KNX B8-TH contains both switch outputs for temperature and humidity as well as PI controllers for heating/cooling and ventilation. The binary inputs can be configured as switches, up/down buttons, dimmers or encoders in various configurations.

Due to its compact design, the interface fits into a switch box. The binary contacts are connected using the cables supplied with the delivery.

Sensors for KNX B8-TH:

N° 30525 TH-UP basic, indoor sensor (temperature, air humidity)
N° 30513 T-NTC-ST, feed/contact probe for temperature measurement

  • KNX B8-TH, connection side KNX B8-TH, connection side
  • KNX B8-TH with sensors (optional accessories) KNX B8-TH with sensors (optional accessories)
  • Award for KNX B8-TH Award for KNX B8-TH
  • 8 binary inputs (button interfaces for potential-free contacts) 
  • 1 input for temperature/air humidity sensor TH-UP basic. Sensor for wall mounting in 55 mm standard frames of switch programmes 
  • 1 input for temperature sensor T-NTC-ST 
  • Bus warning with regard to whether the values for temperature and air humidity are within the comfort field (DIN 1946)
  • Dewpoint calculation 
  • Switch outputs for temperature and air humidity depending on threshold values, adjustable via parameters or communication objects
  • PI-controller for heating (one or two-stage) and cooling (one or two-stage) according to temperature. Regulation according to separate setpoints or basic setpoint temperature 
  • PI controller for humidity according to humidity: Dehumidifying/ humidifying (single level) or dehumidifying (single or double level) 
  • 4 AND and 4 OR logic gates, each with 4 inputs. All switching events as well as 16 logic inputs (in the form of communications objects) can be used as inputs for the logic gates. The output of each gate can be configured optionally as 1-bit or 2 x 8-bit 
  • Configuration via ETS


Dimensions W × H × Dapprox. 38 mm x 49 mm x 18 mm
Weightapprox. 20 g (interface)
approx. 30 g (interface incl. connection lines)
Ambient temperature-20…+70 °C
Ambient humiditymax. 95 % RH, non-condensing
Storage temperature-30...+85°C
Overvoltage categoryIII
Degree of contamination2

KNX bus:

KNX mediumTP1-256
Configuration modeS-Mode
Group addressesmax. 254
Assignmentsmax. 254
Communication objects254
Nominal voltage KNX30 V DC SELV
Power consumption KNX10 mA
ConnectionKNX plug terminals
Duration after bus voltage restoration until data is receivedapprox. 5 seconds


Number8× binary inputs
1× sensor TH-UP basic, art. no. 30525
1× sensor T-NTC-ST, art. no. 30513
Executionare at KNX potential (SELV)
Cable length binary inputsapprox. 30 cm, with wire end ferrule 0.14 mm², 8 mm long.
Maximum cable length: 10 m
Contact voltageapprox. 3,3 V
Contact currentapprox. 330 μA
ConnectionConnection cable pluggable