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200M Meteorological System

Product Description

The Model 200M is a complete instrument for the measurement of Atmospheric Dew Point, Ambient Temperature, % Relative Humidity, or other Psychrometric Variables. It employs the very reliable optical chilled mirror sensing technique which provides a primary measurement of dew point, and is traceable to NIST. The Model 200M is ideally suited for installations requiring continuous, automatic, and unattended measurement of humidity over a very wide range.

Automatic Balance Control (ABC) cycle corrects the light reducing effects of mirror contaminants and allows for continuous monitoring and virtually maintenance-free operation. This is the first and only chilled mirror technology that truly reduces the need for cleaning by the incorporation of self-diagnostics, which indicates to the user, locally via an LED light source and remotely via logic level TTL signal, when and if maintenance is required.


  • Primary measurement technique
  • High accuracy and reliability
  • Certificate of Traceability to NIST provided
  • Sensing scheme discriminates between dew and contamination
  • Reduces maintenance requirements
  • No drift, no hysteresis
  • Fast response
  • No sensor calibration required
  • Self-diagnostics and continuous unattended operation. No balancing or other adjustments required
  • Chilled mirror sensor selection required


  • Atmospheric Sciences