Mixed Gas Flow Meters

Thermal Mass Flow Meters for Mixed Gas Applications

Mixed gas flow meters from Fox Thermal deliver the highest level of accuracy for a wide range of applications. The Gas-SelectX® gas selection feature - available on the FT1, FT4A, and FTX products - allows the user to create a custom gas mix ideal for mixed gas processes without the need to send the meter back to the factory for recalibration.

Help Me Choose A Flow Meter
Industrial oil and gas processes require mixed gas flow measurement.

Fox Thermal Mixed Gas Flow Meters Provide

Direct Mass-Flow Measurement

Fox Thermal flow meters deliver a direct reading of the mass flow rate of natural gas and other gases – without the need for temperature and pressure compensation.

Wide Measurement Range

Fox Thermal mass flow measurement technology provides excellent repeatability and an exceptionally broad measurement range of up to 1000:1.

Reprogrammable Gas Mixes

The Fox Thermal Gas-SelectX® feature, available in models FT1, FT4A, and FT4X, allows them to be reprogrammed to a changed gas mixture in the field.

How our Mixed Gas Flow Meters Work

Flow meters from Fox Thermal deliver the highest level of accuracy in real time—the responsiveness required in a variety of mixed gas flow metering applications.

In contrast with volumetric flow meters, Fox Thermal’s thermal mass meters use a constant temperature differential (∆T) technology for a mass flow rate measurement of gases.

The thermal mass flow sensors consist of two Resistance Temperature Detectors (RTDs). A Reference RTD measures the gas flow temperature. Then the instrument heats the second RTD to a constant ∆T above the gas temperature, which measures the cooling effect of the fluid flowing through the pipe. The electrical power required to maintain a constant temperature differential is directly proportional to the gas mass flow rate.

If you’re not sure which Fox Thermal meter is right for your mixed gas application, use our Help Me Choose app to find the ideal meter, or Contact Us for help today.

Help Me Choose A Flow Meter
Fox Thermal's mixed gas flow meters.

Gas-SelectX® for Superior Mixed Gas Flow Meter Applications

For complex calibrations based on gas composition analyses, all Fox Thermal mixed gas flow meters provide NIST-traceable calibrations. In applications where mixed gases change composition over time, you'll need a more flexible solution to keep your process running.

Fox Thermal Models FT1, FT4A, and FT4X can be programmed in the field using the Gas-SelectX® feature. As the gas composition changes, simply access the gas composition settings in Gas-SelectX® to reprogram the percentages of component gases. This will help you avoid sending the mixed gas flow meter back to the factory for recalibration.

The Fox Thermal Model FT4A is equipped with the Gas-SelectX® feature, making it ideal for the measurement of mixed gases.

Applications & Common Mixed Gases

Fox Thermal flow meters provide accurate mixed gas flow measurement in real-time for a variety of oil & gas applications, including flare gas, vent (flash) gas, natural gas custody transfer, and LPG gas.

Other applications requiring mixed gas flow measurement devices include:

  • Biogas and digester gas monitoring for environmental tests
  • Biogas flow from landfills, agricultural (dairy or swine) operations, or wastewater treatment plants
FBiogas is a common mixed gas application for thermal mass flow meters.

Use This Online Tool to Select the Right Flow Meter Model for Your Mixed Gas Application

Our new app can help you choose the right flow meter model fast.

If you’re not sure which mixed gas flow meter is right for your needs, our Help Me Choose app walks you through a short series of questions to help you choose the ideal meter.

Once you’ve selected a model, fill out the questions in our meter configurator form.

Next, enter your process data and measurement requirements into our automated product configurator. Drop-down menus and Help icons will guide you to answer each question.

Save and submit your application data to us for a quote - it’s that easy!

Save the data you entered into the configurator to create a PDF with a model code and AppID. When you're ready, submit your application to Fox Thermal for a quote.

Discover the Fox Thermal Advantage

Flow Meters for Mixed Gas Applications

fox thermal product ft1

Model FT1

The Model FT1 thermal flow meter is available with Gas-SelectX® and can be easily reprogrammed in the field with the help of DDC-Sensor™ for calculating accurate gas correlations. It can measure a single gas or a mixture of up to 5 specified gases. The CAL-V™ Calibration Validation test feature ensures the meter retains its original NIST calibration.

Model FT1
fox thermal product ft2A meter

Model FT2A

Available in an extended temperature operating range, the Model FT2A can be NIST-calibrated to measure an extensive list of dry pure gases and gas mixes.

Model FT2A
fox thermal product ft3 meter

Model FT3

The FT3 can operate over higher temperatures and measure a wide range of dry pure gases and gas mixes. Comes with CAL-V™ and Zero CAL-CHECK® to ensure the meter retains the NIST calibration in the field. An optional Data Logger is available.

Model FT3
fox thermal product ft4A meter

Model FT4A

This versatile gas flow meter is available with CAL-V™ Calibration Validation, DDC-Sensor™, and Gas-SelectX®. These features allow it to be reprogrammed in the field to measure any combination of gases in the gas mix menu in 0.1% increments to create a custom gas mix.

Model FT4A
fox thermal product ft4X meter

Model FT4X

The Model FT4X features CAL-V™ Calibration Validation, DDC-Sensor™, and Gas-SelectX®. For oil & gas applications affected by BLM 3175 and API 14.10, the FT4X is accuracy compliant. It also comes with a built-in data logger for advanced record-keeping and data retention that maintains a 7-year history.

Model FT4X

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News & Innovation

Understanding Flow Meter Accuracy Specs

Accurate and repeatable flow rate data can help you maintain the calibration of mixed gas thermal flow meters.

Learn More
Flow Meter Comparison

This discussion of the different types of flow meters will help you understand the best mixed gas flow measurement technology for your application.

Learn More
More Literature

Download helpful whitepapers, product literature, and more, including Fox Thermal Application Guides, data sheets, and case studies.

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