High-Accuracy QuadraTherm Gas Flow Meters

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QuadraTherm 640i/780i flow meters are the industry’s most precise thermal mass flow meters with an accuracy of +/- 0.5% of reading above 50% of full scale. Offered in both an insertion and inline versions, the QuadraTherm is ideal for precision gas flow measurement of natural gas, as well as other gases such as hydrogen, CO2 nitrogen and propane. Now with on board qMix gas mixing software, for the first time with thermal technology, customers can create and upload new gases as the gas composition changes-all without sending the meter back to the factory for recalibration. Buy online for next day shipping!

Proven QuadraTherm immersible thermal technology offers:

  • Direct gas mass flow rate measurement
  • Industry's most stable dry sensor with proprietary DrySense
  • Wide turndown ratio
  • Very low pressure drop, no moving parts and application flexibility
  • Change gas in the field or build your own gas composition with qMix
  • Extreme precision with "percent of reading" accuracy, which for the first time rivals accuracies of Coriolis technology

Choose your gas flow meter from Sierra today for more accurate measurement of air, natural gas, propane, hydrogen, nitrogen and CO2.

  • Related Products
  • QuadraTherm® 640i

    Industry's Most Accurate Air / Gas Thermal Insertion Mass Flow Meters

  • QuadraTherm® 780i

    Highest Air/Gas Mass Flow Measurement Accuracy in Industry

  • qMix Gas Mixing Feature

    Field-Update For Gas Composition Changes

  • Measure Flare Gas in Real Time

    QuadraTherm® qMix RealTime
    Flare Measurement System

  • Related Videos
  • Sierra Instruments' Mission

  • Sensor Design for Thermal Mass Flow Meters

  • Exploring In-Situ Thermal Flow Meter Calibration Validation

  • How qMix Works

  • How Thermal Mass Flow Meter Technology Works

  • Flow Meter Recalibration and Repair Made Easy

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