Series-HC2A-S

Supported Applications

The Rotronic HygroClip2 ADVANCED (HC2A) series comprises digital humidity and temperature probes based on AirChip3000 technology. These hot-swappable sensors are designed for use with HygroClip2 generation instruments, including transmitters, data loggers, and hand-held devices, as well as standalone applications via analog outputs or UART interfaces.

Documented application areas include:

• Meteorology and weather stations (including snow guns)
• Pharmaceutical industry processes
• Biohazardous material decontamination and sterilization using hydrogen peroxide (H₂O₂)
• Clean rooms, incubators, and medical equipment sterilization
• Food processing environments
• Paper and textile industries
• Building services climate monitoring

Operating Conditions & Performance

The series supports a broad measurement envelope depending on the specific model variant. Standard humidity measuring ranges are 0...100 %RH, with some variants specified for 0...90 %RH.

• Temperature Ranges: Application temperatures span from -50 to 100 °C (-58...212 °F) for standard models. The HC2A-S3A meteorological probe operates from -50 to 80 °C (-58...176 °F). Specialized industrial variants (HC2A-ICxxx, HC2A-IExxx) support sensor head temperatures up to 200°C for peak loads of 100 hours maximum and continuous load up to 190 °C.
• Accuracy: Accuracy varies by precision class. High Precision models (e.g., HC2A-SH, HC2A-S3H) offer ±0.5 %RH or ±0.1 K at 10...30 °C. Standard Precision models provide ±0.8 %RH and ±0.1 K under the same conditions. The hydrogen peroxide variant (HC2A-S-HH) specifies an accuracy of ±1.0 %rh, ±0.1 K @ 10...30°C before and after diffusion phase.
• Stability: Long-term stability is documented as <1 %RH per year with clean air for models utilizing the HYGROMER HT-1 sensor element.

Configuration Options

The HC2A series offers extensive configuration options regarding housing materials, filtration, and output signals to suit diverse installation requirements.

• Housing Materials: Available in Polycarbonate (black or white), Polyethylene (white standard for solar radiation avoidance), Sintered steel 1.4404, and Stainless steel 1.4301.
• Filtration Options: Filters are available to protect the sensor element. Standard dust filters include Polyethylene (40 μm). Additional options feature PTFE (10 μm), Wire mesh 1.4401 (10 μm), and specialized carriers for high-temperature or corrosive environments.
• Output Signals: Probes provide two linear analog outputs (2x 0...1 V) and a digital UART serial interface (RoASCII, 19200 baud fixed; MODBUS available on HC2A-S3A via HW5 software). Analog defaults are scaled to Humidity (0...100 %RH = 0...1 V) and Temperature (-40...60 °C = 0...1 V), with user reconfiguration possible for Dew point or Frost point.
• Power & Electrical: Supply voltage is 3.3...5 VDC with a current consumption of approximately 5 mA (adjusted at 3.3 VDC). Load resistance must be > 10 kΩ.

Key Product Differences

The series includes distinct model families tailored to specific environmental challenges:

• HC2A-S / HC2A-SH (Standard & High Precision): General-purpose probes with Polycarbonate or Polyethylene housings. The SH variant utilizes the HYGROMER HT-1 sensor for ±0.5 %RH accuracy.
• HC2A-S3 / HC2A-S3H (Meteo 4 Standard/High Precision): Designed for meteorological applications with white housings to minimize solar heating effects.
• HC2A-S3A (High-End Meteo): Features the HYGROMER HM1-SK sensor element, optimized for weather stations and snow guns with an operating range of -50...80 °C.
• HC2A-SM / HC2A-SM-HH (Steel Probe & Hydrogen Peroxide): The SM variant uses a stainless steel 1.4301 housing for high-temperature applications (-100...200°C). The HH variants are specifically designed for hydrogen peroxide sterilization processes, compatible with biohazardous material decontamination and FDA CFR21 Part 11 / GAMP requirements.