Michell Instruments MDM300 Series

Portable Dew-Point Hygrometer

Envent is working in partnership with Michell Instruments to provide a more comprehensive product offering of online process instruments designed specifically for measuring moisture in Natural Gas. The MDM300 Series sensor responds quickly to changes in moisture whether from dry to wet or wet to dry. This means there is no need to wait between measurements, allowing operators to make more measurements in a day.

The general purpose MDM300 is suitable for safe area use, while the intrinsically safe MDM300 I.S. has global hazardous area approval from ATEX, IECEx, FM, CSA, GOST and INMETRO and is able to measure moisture in flammable gases such as natural gas or bio-gas.


  • Features
    • Repeatedly fast measurements at low pressure from less than 15 minutes for T95 to -60°C (-76°F)
    • Higher pressure measurements possible – up to 350 barg (5076 psig)
    • Long battery life: up to 48 hours of typical use between charges
    • Intuitive application kits allow quick and straightforward connection to your sample point
    • Durable, yet easy to handle and operate: designed for use in industrial environments
    • Lightweight: less than 1.5kg (3.3lb)
    • 13-point traceable calibration certificate
  • Downloads
  • Certification

    For any certification documentation please make a request through the contact us form. 

  • Applications
    • Dew point in natural gas processing and pipelines
    • Monitoring of desiccant dryers for compressed air or plastic moulding equipment
    • Moisture measurement in high-voltage switchgear quench gas
    • Moisture measurement in petrochemical refineries
    • Industrial gas production and transportation
    • Medical gas quality
    • Dew-point measurement in metallurgical applications
  • Specifications


      MDM300 & MDM300 Intrinsically Safe
    Measurement Technology  Michell ceramic metal-oxide moisture sensor

    ±1°C (±1.8°F) from -60 to +20°C (-76 to +68°F) dew point
    ±0.2°C (±0.36°F) temperature

    Calibrated Range Spot Checks: -70...+20°C (-94...+68°F) dew point
    Online Analysis: -100...-70°C (-148...-94°F) dew point

Contact us to learn more about this product

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