Rotronic Hygroflex3 HF3 Humidity & Temperature Measurement HVAC Transmitter

Rotronic Hygroflex3 HF3 Humidity & Temperature Measurement HVAC Transmitter

Rotronic Hygroflex3 HF3 Humidity & Temperature Measurement HVAC Transmitter

Rotronic Hygroflex3 HF3 measures relative humidity and temperature HVAC transmitter achieves a high degree of accuracy that has rarely been seen before.

In combination with advanced sensor technology and integration, the Rotronic Hygroflex HF3 provides superb functionality, taking humidity, temperature and dew point measurement to a whole new level of performance and reliability (< 2 %rh / 0.3 K).

Based on Airchip 3000 technology, the unique features of the Rotronic Hygroflex HF3 such as the advanced sensor technology and integration provide superb precision and state-of-the-art functionality.

Typical applications and industries include HVAC, food industry, building services equipment, paper, textile and pharmaceutical.

Rotronic Hygroflex3 HF3 Humidity & Temperature Measurement HVAC Transmitter Product Benefits

  • Highly versatile – With one or two selectable and scalable analog outputs that are assignable to relative humidty, temperature or dew point, the highly versatile Hygroflex HF3 also features features 2-wire or 3/4-wire systems.
  • Fast response and precision measurement – By de-coupling the Rotronic PT100 temperature sensor from the probe thermal response is significantly improved. The Rotronic Hygroflex HF3 also utilises  Pt100 Class A sensors for maximum accuracy.
  • Airchip 3000 Technology – The Airchip 3000 technology compensates humidity and temperature over 30,000 reference points. In addition the Airchip 3000 offers 2,000 data point memory and dew/frost point calculation.
Rotronic Hygroflex3 HF3 Humidity & Temperature Measurement HVAC Transmitter Components

Rotronic Hygroflex3 HF3 Humidity & Temperature Measurement HVAC Transmitter Components

In addition to being used with the Rotronic HygroClip 2, the HC2-S probe can be used as a standalone device using either the analog output signals or the probe digital interface.

Connectors, cables and digital interface adapters are available to this purpose. Digital integration with OEM applications is facilitated by the probe communication protocol options.

Key user functions of the Rotronic Hygroflex HF3 humidity and temperature transmitter include:

  • Relative humidity, temperature measurement and dew point calculation
  • Outstanding accuracy and repeatability
  • Hygromer® IN-1 humidity sensor
  • Auto-diagnostics and automatic correction
  • Freely selectable and scalable analog outputs

Rotronic HYGROFLEX3 HF3 Humidity And Temperature Transmitter

Product Specifications

Probe Accuracy Measurement Range Standard Output Scaling Weight Min. / Max. load Change In Signal Type Current Consumption Long-Term Stability
±2.0 %rh / 0.3 K (±1.0 %rh / 0.1 K Type R) -40…60 °C / 0…100 %rh 0…1 V = -40…60 °C / 0…100 %rh 120g V-signal:≥1 kΩ/V / mA signal: ≤ 500 Ω HF33 only 4.5mA at 3.3 VDC <1 %rh/ year

Humidity Sensor Temperature Sensor Response Time T 63 Housing Max. Air Velocity Type Of Output Signals Probe Material
Rotronic Hygromer IN-1 Rotronic Pt100 Class A <10 sec. ABS 20 m/s at probe 0…1 V, 0…5 V, 0…10 V, 0(4)…20 mA PEEK

Rotronic Hygroflex HF3 Humidity & Temperature Probe

Rotronic Hygroflex HF3 probes measure humidity, temperature and also calculate dew/frost point.


  • Accuracy: ±2 %rh / ±0.3 K at 23°C ±5 K
  • Temperature limit at probe: -40…60 °C / 0…100 %rh
  • Range of application electronics: -40…60 °C / 0…100 %rh, -10…60 °C with LCD
  • Service interface
  • Adjusted at 23 °C and 10, 35, 80 %rh

Rotronic Hygroflex HF3 Humidity  & Temperature hvac transmitter – output options

The high flexibility of the Hygroflex HF3 allows the user to freely select the output parameters and scale each output.

The available output parameters pictured below are for the Rotronic HF32 series (2 wire technology) and Rotronic HF33 series (3/4 wire technology).

Rotronic Hygroflex HF3 HVAC Transmitter Output Options - Left to right HF32, HF33 series

Rotronic Hygroflex HF3 HVAC Transmitter Output Options – Left to right HF32, HF33 series


The pharmaceutical industry is one of the largest users of humidity measurement equipment. Most drugs are sensitive to variations in humidity and moisture levels, so these need to be considered and controlled using measurement instruments, probes and sensors for the final products to be consistent in quality and performance.

Humidity Measurement Applications

Humidity instruments are used to both control (transmitters) and monitor (transmitters or data loggers) these conditions during “accelerated conditions” drug testing.

Production machines, driers, tableters, and coaters are all sensitive to humidity – quality control requires machine monitoring, area monitoring and final product Equilibrium Relative Humidity (ERH) measurement.

Clean room environments are humidity critical – environmental monitoring system (EMS) and measurement is validated to conform with regulatory requirements.


View the current Rotronic catalogue :


T&D distribute Rotronic probes, instruments, transmitters, data loggers, indicators and sensors for the measurement of dew point, flow, air velocity, process pressure, carbon dioxide and temperature. Click an icon for further information…..


Rotronic - Dew Point Measurement

Low Dew Point

Rotronic - Flow Measurement

Flow & Air Velocity

Rotronic - Process Pressure Measurement

Process Pressure

Rotronic - CO2 Measurement

Carbon Dioxide

Rotronic - Temperature Measurement


➡ Did you know? T&D supply VEGA process instrumentation for pressure, level and point level (switching) measurement.

Data Sheets