RHT Duct

Humidity transmitters with temperature output for duct

RHT Duct is a relative humidity transmitter with temperature output installed in air ventilation duct. Illuminated display ensures easy readability also from a distance. The RHT has a screwless lid and an easily adjustable mounting flange that make the installation of the device easy.


RHT Duct series devices include:

• Separate output for each measurement parameter (rH and T)

• Offset feature enabling field calibration for each measurement parameter (rH, T)

• Mounting flange


RHT Duct series device options offer:

• Clear backlit display

• Modbus RTU interface

• 4-20 mA proportional output

Technical details

Accuracy: Temperature: <0.5 °C
Relative humidity: ±2…3 % rH at 0…50 °C and 10…90 % rH
Total error band includes accuracy, hysteresis and temperature effect over 5...50 °C and 10–90 % rH
Measuring units: °C, % rH
Measurement elements: NTC10k temperature sensor, thermoset polymer capacitive sensing element for humidity
Supply voltage: 24 VDC/VAC ±10 %
Output signal 1: 0/2…5/10 V (linear to rH)
Output signal 2: 0/2…5/10 V (linear to Temp)
Optional output signal 3: 4...20 mA (linear to rH) (A model)
Optional output signal 4: 4...20 mA (linear to Temp) (A model)
Operating temperature: 0...+50 °C
Protection standard: IP54

RHT Duct

RHT Duct-D


Product series

Relative humidity transmitter, analog outputs
Relative humidity transmitter, Modbus communication


Duct mount


Voltage output
Voltage and current output


With display
Without display

Other Humidity transmitters: