Chilled Mirror Hygrometer

  • A primary measurement instrument, ideal for laboratory and precision applications
  • 3 Stage Chilled Mirror Hygrometer, with integral cooling
  • Precise measurement to -95 °C frost/dew point, 37 ppb(V)
  • High accuracy instrument (±0.2 °C dewpoint) for laboratory or similar applications
  • Accuracy ±0.2 °C dewpoint
  • Backlit LCD displaying readings in °C or °F dewpoint and ppm(V)
  • Optional temperature and pressure sensors are available
  • RS232 Serial comms
  • Pressure measurement can be displayed using the optional pressure transducer
  • 2 programmable alarm relays
  • Automatic Balance Control (ABC), for fast and easy measurement and control
  • Supplied with a Calibration Certificate traceable to National and International Humidity standards

Model CMH Chilled Mirror Hygrometer accurately measures the dewpoint of a gas by cooling a mirrored surface, over which the gas flows until a layer of dew forms on the surface.

The Chilled Mirror Dew Point Hygrometer utilises a 3-stage cooler combined with an integral refrigeration unit to measure the dewpoint in gases from below -95 °C to 20 °C (-139 °F to 68 °F) dewpoint with an accuracy of ±0.2 °C dewpoint.

This primary measurement principle makes the CMH-RPC the ideal instrument for laboratory, scientific, and research applications and a reference instrument for checking and dewpoint calibration of Dewpoint Meters, Dewpoint Transmitters, Dew Meters and Dewpoint Analysers.

Please do not hesitate to contact us for price, delivery, or details of your local distributor.

Sensing Element Three Stage With Additional Refrigeration
Analogue output 0-5 Vdc, 4-20 mA, 0-10 Vdc, or 0-20 mA

User Scalable to Drive Peripheral Devices

Available Simultaneously, One Output per Measurement Parameter

Scalable Throughout the Entire Operating Range of Psychometric Variables

Programme via Front Panel

Serial Output RS232 Communication With Terminal, Printer, or Computer

Remote Programming

Data Output Such as Dew Point and Alarm Status

Power Supply 110 Vac or 230 Vac, 50/60 Hz (Specified at Order)
Dewpoint Range -95 °C Dewpoint to +20 °C Dewpoint at 22 °C Ambient Temperature
Electromagnetic Compatibility (EMC) Complies with BS EN ICE 61326-1
Accuracy +/-0.2 °C (0.36 °F) dewpoint
Manual Balance Control (MBC) Automatically Corrects for Most Mirror Contaminants

Automatically Re-Balances the Optics at Switch On

Programmable Automatic Balance Cycle (PABC) Programmable Interval of Balance Control for Greatest Convenience

Increases the Length of Unattended Operation

Dual Alarm Capability User Programmable

Can be set for latching or auto-reset mode

Pressure transducer input for psychometric variable Optional Extra
Temperature sensor for RH calculation Optional Extra
Factory Calibration Supplied with a calibration certificate traceable to National and International Humidity standards. We recommend annual laboratory calibration
Sample Flow Rate 0.25 to 2.4 L/min (0.5/5.0 SCFH)
Sample Pressure 0 to 5 bar (0 to 75 psia)
Weight 47 kg
Dimensions Height 600 mm, Width 520 mm, Depth 435 mm
Manufacturer’s Warranty 24 months in case of defective parts or faulty workmanship