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Product code: 30805001
KNX-Sensor / controller for monitoring and control of soil moisture and soil temperature. (PT1000) with Watermark-WM (maintenance free) soil moisture probe. The integrated controller allows automatic irrigation dependent on the real demands of water.
Price (Excluding VAT)


    The measuring system SK08-BFT-WMT records the soil humidity which is measured by the Watermark-Sensor as well as the
    soil temperature.

    The measured values can be displayed and used for controlling functions.

    The integrated controller allows automatic watering of areas dependent on the actual needs of the landscaping.

    The user must make sure the device is correctly set, as the demands of the landscaping and soil structure are very diverse and a general setting for all uses cannot be made. Previous experience with manual watering length and amount is an acceptable way to set the parameters of the device.

    Using the sensor does not replace regular inspection of the watering process.

    A number of controller models with various functions are available.

    KNX sensors are set up using the ETS ( KNX Tool Software ) with the associated application program. The device is delivered unprogrammed.

  • All functions are parameterized and programmed by ETS.

    The controller can be switched on or off by activation or locking via the KNX bus.


  • Measured value Soil Humidity ( Suction Power in Pa ) and Soil Temperature
  • Two position controller with switch and pulse 1-bit output
  • or PI controller with continuous 8-bit or pulse-width modulated 1-bit output
  • Measured Value can be periodically displayed or when value changes
  • Adjustable periodic display of control variable
  • Adjustable release and lock with all controllers
  • Threshold alarm for upper and lower thresholds
  • Auxiliary quantity of set value or threshold via the bus
  • Calibration of the sensor (offset cancellation)

  • Areas of Application

  • Decentralized irrigation and watering control for gardens and landscaping
  • Active sprinkling control for flat roofs with vegetation
  • Industrial soil humidity controller for areas such as snail and insect breeding
  • Recording of soil humidity and soil temperature
  • Sprinkling control via integrated control functions
  • Environmentally friendly and timed sprinkling control ( early afternoon )
  • Alarm when upper or lower threshold for soil humidity is surpassed

Technical Details


  • Bus Voltage: KNX Bus 21...30VDC
  • Bus Current Consumption: 10mA
  • Measurement: Soil moisture ( suction power ), soil temperature
  • Measuring range soil moisture: 1 .. 2000 hPa/mbar, 1 .. 200,000 Pa
  • Accuracy: soil moisture: 1 hPa/mbar, 200,000 Pa
  • Resolution: soil moisture: 0,01 hPa/mbar, 1 Pa
  • Measuring range soil temperature: -25 ... 45 C
  • Accuracy: range soil temperature: +/- 1 C
  • Probe: Watermark-WMT with PT1000
  • Probe Cable Length: 5m



    Technology KNX
    Brand ARCUS
    Mounting Surface
    Operating voltage KNX Bus (29VDC)
    IP rating IP65

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