Optidew Vision

Precision Dew-Point Meter

The Optidew Vision precision dew-point meter is based on the proven, fundamental optical dew-point measurement principle, giving long-term drift-free performance. It offers a wide measurement range from the equivalent of <0.5 to 100% RH at ambient temperature (dew point range: -40 to +90°C (-40 to +194°F), and up to +130°C (+266°F) with high temperature option).

The Optidew is an excellent entry level calibration reference, supplied as standard with a fully traceable in-house calibration or optional UKAS-certified calibration. Its simple operation makes it possible for anyone to use with minimum training. Simply connect the instrument, power it up and measurement will begin automatically.

Product Features

  • Fundamental drift-free dew-point measurement
  • Convienient, transportable package
  • ±0.2°Cdp (±0.36°Fdp) accuracy; optional higher accuracy available
  • High temperature sensor option to +130°C (+266°C)
  • NEMA-12 bench-top housing
  • Display and output of multiple engineering units
  • High pressure sensor option to 25 MPa (250 barg / 3625.9 psig)
Optidew Vision

More Information

Technical Specification

Measurement Accuracy* ±0.2°Cdp (±0.32°F)
±0.15°Cdp (±0.27°Fdp) accuracy optional
±0.1°C (±0.18°Fdp) temperature
Measurement Units °C, °F dew point; %RH; °C, °F temperature; g/m3; g/kg; aW; ∆ (t-t dew point)
Response Speed 1°C/sec plus settling time (dew point dependant)
Power Supply 90 to 264 V AC OR 127 to 370 V DC, 47 to 440 Hz, 20 W max. Internally fused, 4A quick blow
Dew-Point Sensor
Sensor1 Stage2 StageHigh temp PEEK
Dew-Point Range–30°Cdp (–22°Fdp) @ sensor temperature of +20°C (+68°F)

+90°Cdp (+194°Fdp) @ sensor temperature of +90°C (–194°Fdp)
–40°Cdp (–40°Fdp) @ sensor temperature of +20°C (+68°F)

+90°Cdp (+194°Fdp) @ sensor temperature of +90°C (–194°Fdp)
–40°Cdp (–40°Fdp) @ sensor temperature of +20°C (+68°F)

+130°Cdp (+266°Fdp) @ sensor temperature of +130°C (+266°Fdp)
Temperature Range-40 to +90°C
(-40 to +194°F)
-40 to +90°C
(-40 to +194°F)
-40 to +130°C
(-40 to +266°F)
%RH Range<2 to 100%<0.5 to 100%<0.5 to 100%
Min Measured Dew Point @ +20°C (+68°F)-30°C (-22°F)-40°C (-40°F)-40°C (-40°F)
Mirror Material Options Gold plated copper (standard)
Gold stud
316 stainless steel stud**
Platinum stud**
**Recommended for special applications only, consult Michell Instruments before ordering
Sensor Body Material Options Acetal (standard)
High temperature PEEK
316 stainless steel**
Anodized aluminum**
**Recommended for special applications only, consult Michell Instruments before ordering
Temperature Measurement 4 wire Pt100, 1/3 DIN class B
Sample Flow 0.1 to 2 Nl/min (0.21 to 4.23 scfh) (in sampling block)
Maximum Velocity 10 m/sec (32.8 f/sec) direct insertion
30 m/sec (98.4 f/sec) with sintered guard
Pressure Standard unit: 2 Mpa / 20 barg / 290 psig (max)
Ingress Protection: IP66
High Pressure version: 25 Mpa / 250 barg / 3626 psig (max)
Ingress Protection: IP65
Cable Length 2m (6.6’); 50m (165’) maximum (up to 250m (820.2’) on special request)
Remote PRT
Temperature Measurement 4-wire Pt100 1/10 DIN class B
Cable Length 2m (6.6'); 50m (164') maximum (up to 250m (820') on special request)
Transmitter Electronics
Resolution 0.1 for °C, °F and %RH
0.01 for g/m3 and g/kg
Outputs Analog: Two channels 0/4-20 mA
Digital: RS232 (RS485 optional)
Alarm: Volt free contact, 2 A @ 30 V DC
Status LEDs DCC / Alarm Status
Operating Temperature -20 to +50°C (-4 to +122°F) ambient
Enclosure Standing case with carry handle Panel mounting kit optional
Ingress Protection IP54 (NEMA 2)
Cable Pack Mains, RS232 cable and output connector
Calibration 4-point traceable in-house calibration as standard, UKAS accredited calibrations optional – please consult Michell Instruments
*Measurement accuracy means maximum deviation between instrument under test and corrected reference. To this must be added the uncertainties associated with the calibration system and the environmental conditions during testing and subsequent use.

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