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  • RH401


  • Triple display with backlighting
  • Displays Air temp+RH+surface temp or Dew Point+RH+surface temp or Wet Bulb+RH+surface temp
  • Built-in InfraRed Thermometer with laser pointer and 8:1 distance to target ratio
  • Adjustable emissivity from 0.3 to 1.0
  • Precision humidity capacitance sensor is retractable for protection during transportation and storage
  • Calculates T1 (IR Surface Temperature) - DP (Dew Point) differential

The Extech RH401 psychrometer combines accurate humidity and dew point readings with a convenient, non-contact infrared thermometer. The Extech RH401 psychrometer has a triple display with backlighting, showing your choice of three setups:

  • Air Temperature, Relative Humidity & Surface Temperature
  • Dew Point, Relative Humidity & Surface Temperature
  • Wet Bulb, Relative Humidity & Surface Temperature

The Extech RH401 psychrometer with infrared thermometer also has the ability to perform multiple temperature and humidity calculations making it ideal for temperature / humidity monitoring in schools, offices, and manufacturing or storage areas. A built-in RS-232 interface makes transferring data to your PC easy for further analysis. Other features of the Extech RH401 psychrometer include data hold and auto power off.

The Extech RH401 psychrometer comes complete with four AAA batteries and convenient carrying case.