DEWRay - Portable Dewpoint Hygrometer 

The DEWRay portable is a chilled-mirror Dewpoint Hygrometer based on fundamental principles giving high accuracy and log term stability.


The DEWRay is a precision dewpoint hygrometer which works on the proven fundamental optical dew-point measurement principle (see technology section for detail information). The DEWRay split beam reflex detection method is able to detect whether ice or super-cooled is present on the mirror and compensate accordingly. This feature, unique to STORK Instruments, avoids the possibility of measurement errors of up to 4°C  dewpoint which is an inherent danger in competing cooled mirror instruments.



  • Proven chilled Mirror principle
  • Split beam reflex sensor
  • Super-cooled water compensation
  • Lithium-Ion battery for long term operation between charges
  • In-built data logger
  • Calibration traceable to international standards
  • AZOR Mirror self-cleaning fincion
  • Blue Graphic display




Measurement range:

  • -40°C to +20°C dewpoint
  • -40°F to +68°F dewpoint
  • 125 to 23,000 ppm(v)
  • Accuracy: +/-0.2°C dewpoint
  • Outputs: 4-20mA, (0-20mA)
  • Power Supply: 90-150V AC, 12V DC
  • Operating pressure: 0-2,5 MPa
  • Flow rate: 0.1-0.5 l/min
  • Case material: Polypropelene
Measurement Units °C, °F for dew point and temperature; % RH: gm-3 g/kg-1 aw; Δ (t-tdp)
Response Speed 1°C s-1 + settling time (dew-point dependent)
Power Supply                                                                     90 to 264 V, 47/63 Hz. IEC Connection with integral filter


Mirror Gold plated copper
Temperature Measurement 4 wire 100 Ω 1/3 DIN Class B Pt100
Sample Flow Rate 0.1 to 2 Nl/min
Ingress Protection                     IP65 (NEMA 12) 2,5 MPa (25 Barg) 


Resolution                                                 0.1 for ºC, ºF and % RH, 0.01 for gm-3 and g/kg-1
Outputs Analogue: Two channels 4-20 mA or 0-20 mA
Digital: RS-232 (RS-485 optional)
Alarm: Volt free contact, 2A @ 30VDC
Status LEDs Power on, DCC and alarm status
Operating Temperature 0 to +40°C ambient


PDF Version