Siemens - Duct Humidity Sensors - QFM Series
  • Australia Post

    Express Parcel and Parcel Post available.

  • New Zealand

    We now ship to New Zeland

  • Contact us

    Our online team is ready to help you by chat and email!

  • Availability

    Check availability on the green button above.


Siemens QFM Series Duct Relative Humidity and Relative Humidity & Temperature Sensors. Designed for applications demanding the highest level of humidity sensing, these sensors are your trusted partners for creating a comfortable and controlled environment.

Key Features:

  • Variety of Models: Choose from a range of models to meet your specific needs. The QFM Series offers options for humidity-only monitoring (available in 5%, 2%, and certified accuracy) or combined humidity and temperature sensing (also in 5%, 2%, and certified accuracy).

  • Display Versions: For enhanced visibility and control, opt for display versions that provide real-time feedback on humidity and temperature changes.

  • Output Options: The humidity-only units are available with either a 4 to 20 mA or 0 to 10 Volt signal output. Combination humidity and temperature units are also available with dual current or voltage versions, ensuring seamless integration with your controller.

  • Replaceable Sensing Tips: The 2% and certified accuracy models come equipped with removable sensing tips. These tips can be easily replaced without disrupting the installation or wiring, making them ideal for applications where measurement accuracy is crucial.

  • Certified Calibration: All certified sensors include a calibration certificate, guaranteeing reliable and accurate humidity measurements. Calibration is performed at three crucial points: 20%, 50%, and 85% relative humidity at 23°C.

Specifications – Humidity Element:

  • Measurement Range: Covering the full spectrum, these sensors can measure humidity from 0% to 100% relative humidity.

  • Accuracy: Enjoy precision with accuracy levels as low as ±2% rh within the range of 0% to 95% rh, ensuring dependable results for critical applications.

  • Temperature Effect: Minimize the impact of temperature fluctuations with a temperature effect of less than 0.1% per degree Celsius.

  • Sensing Element: These sensors utilize capacitive humidity sensing elements, known for their reliability and accuracy.

  • Output Signals: Depending on your requirements, choose between 4 to 20 mA or 0 to 10 Vdc output for humidity-only units. Humidity and temperature units offer 0 to 10 Vdc or 4 to 20 mA outputs, ensuring your controller receives the data in the format you prefer.

  • Polarity Protection: Benefit from added safety with built-in polarity protection.

  • Calibration: Calibration is not needed for these sensors as they come with pre-calibrated accuracy.

  • Time Constant: Experience a rapid response to changes with a time constant of approximately 20 seconds in moving air.

Part Numbers:
QFM2100 Duct Humidity Sensor 0…10V
QFM2101 Duct Humidity Sensor 4…20mA
QFM2150/MO Duct Sensor Humidity/Temperature Modbus RTU (S55720-S467)
QFM3100 Duct Humidity Sensor 0…10V High Accuracy
QFM3101 Duct Humidity Sensor 4...20mA High Accuracy
QFM3150/MO Duct sensor Humidity/Temperature Modbus RTU High Accuracy (S55720-S468)
QFM81.2 Duct Hygrostat 15…95%rh External Setpoint Adjustment
QFM81.21 Duct Hygrostat 15…95%rh Internal Setpoint Adjustment

Frequently Bought Together

Total price $374.00