Humidity transmitters for building automation systems

RHT relative humidity transmitters are engineered for building automation systems in the HVAC/R industry. The RHT measures relative humidity (rH), and temperature (T). RHT devices are available with large touchscreen display making configuration of the device quick and easy.


RHT devices include:

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

• Proportional output options including: voltage (0–10 V, 2–10 V) and current (4–20 mA)

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


RHT series device options offer:

• 2” x 3” touchscreen display

• Field configurable relay for any of the two parameters

• Modbus configuration

Technical details

Accurary: 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: Pt1000 temperature sensor, thermoset polymer capacitive sensing element for humidity
Supply voltage: 24 VDC/VAC ±10 %
Current consumption: max 90 mA (at 24 V) + 10 mA for each voltage output or 20 mA for each current output
Output signal 1: 0/2…10 V (linear to rH), L min 1 kΩ or
4…20 mA (linear to rH), L max 500 Ω
Output signal 2: 0/2…10 V (linear to Temp), L min 1 kΩ or
4…20 mA (linear to Temp), L max 500 Ω
Optional relay output: Potential free SPDT 250 VAC, 6 A / 30 VDC, 6 A with adjustable switching point and hysteresis
Operating temperature: 0...+50 °C
Protection standard: IP20




Product series

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


Wall mount


With relay
Without relay


With display
Without display

Other Humidity transmitters: