
QFM31 Series Duct-Type Humidity and Temperature Sensor
Operating Voltage: C 24V / DC 13.5...35V
Relative temperature and humidity signal output is DC 0...10 V / 4...20 mA
• High precision throughout the entire measurement range
• Features test function
Capacitive humidity measurement principle
• Measurement Range: -40...+70 °C / 0...100 % r. h.
Sensor with LCD display - Application range: -25...+70 °C / 0...100 % r.h.
Usage
QFM31... is designed for HVAC applications where high precision in relative humidity and rapid response times are essential. It measures the full humidity range from 0...100%.
• Facilities for storage and production in the paper, textile, food, chemical, and electronics industries
• Laboratory
• Computer and Electronic Data Processing (EDP) Centers
• Indoor Swimming Pool
Greenhouse
The QFM31... is used for...
• Sensors for control in blowing or returning air
• After the steam humidifier, a sensor for limiting the maximum dew point humidity is used.
• Limited sensors, such as for value display or connection to building control systems
• For measuring enthalpy and absolute humidity, to be used with SEZ220
Installation Precautions
Location
The sensor should be installed at the center axis of the duct. If the sensor is shared with a steam humidifier, the minimum distance should be 3 meters, and the maximum distance should not exceed 10 meters.
Install the flange on the duct and then insert the sensor and tighten it onto the flange.
Attention!
The sealing pad between the housing and base is non-removable; otherwise, the IP 65 protection level cannot be guaranteed.
The sensor components inside the measuring rod are highly sensitive; avoid excessive vibration and other disturbances during installation.
Installation Instructions
Installation instructions are printed on the sensor's packaging.































