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  • Chilled mirror hybrid sensor
  • Model type:
    • OPT401: Bench Top
    • OPT501: Wall Mount
  • Accuracy:
    • ±0.15°C dew point
    • ±0.1°C temperature
  • Measurement range: -40 to 248°F (-40 to 120°C)
  • Touch-screen HMI
  • Sensor types:
    • Polyoxymethylene (acetal, standard conditions)
    • PEEK (poly ether ether ketone, harsh environments)
  • Repeatability: ±0.05°C
  • Sensitivity: ±0.01°C
  • M36x1.5 process connection

The Michell Instruments Optidew Chilled Mirror Hygrometer is available in bench top and wall mount configurations, and features an intuitive touch screen interface for easy local operation. Using the latest developments in chilled mirror technology, it has a response speed comparable to polymer relative humidity sensors, combined with the reliability of drift-free measurements common to all chilled mirror instruments.

Applications for the Optidew include:

  • Reference humidity instrument for climatic and environmental chambers
  • Inlet air measurement for engine testing
  • HVAC testing
  • Environmental monitoring in clean rooms
  • Coating process monitoring – for confectionary and pharmaceuticals
  • Control of humidity for metallurgical processes


Michell Instruments OPT401 Transport Case


Please consider these optional accessories.

Michell Instruments OPT2-SSB Sensor Sampling Block
Sensor sampling block, SS with 1/8in NPT in/out threaded gas ports
Michell Instruments OPT2-ACHS Extended Heatsink
Extended Heatsink for the Optidew Chilled Mirror Hygrometer
Michell Instruments Porous Aluminum Guard
Michell Instruments 6 & 8 Way Plugs
Optidew 6 & 8 Way Plugs for Outputs/Alarms
Michell Instruments OPT2 POM Sensors
1 stage or 2 stage POM dew point sensors
Michell Instruments OPT2-HES-2 Dew Point Sensor
Dew Point Sensor, 2 stage (PEEK)
Michell Instruments OPT2 Pressure Sensor
Pressure Sensor with ranges of 0 to 16 kPa and 0 to 250 kPa
Michell Instruments OPT2-PRT Temperature Sensor
Michell Instruments ASC Cables
Ambient temperature sensor or pressure sensor cables, 0.3m, 3m, 5m, 10m and 20m length available
Michell Instruments OPT2-HTSC High Temp Cables
High temperature cable (Dew Point Sensor), Max 120°C, 3m, 5m, 10m and 20m lengths available
Michell Instruments OPT2-HTASC Cables
High temperature cable (Temp Sensor or pressure sensor), Max 120°C, 3m, 5m, 10m, 20m