Digital Air Flow Meters & Controllers

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From heavy industrial to research and analytical applications, Sierra has a wide range of digital air flow meters and controllers with digital output protocols for easy network integration. Sierra offers air flow meters and across two core technologies: Immersible Thermal and Capillary Thermal.

Configure Your Digital Flow Meter

Immersible Thermal

Sierra's immersible thermal inline and insertion flow meters offer precision measurement for heavy and light industrial applications, such as energy, natural gas measurement, compressed air, oil & gas, general process control applications, and research.

Our industrial mass flow meters range from the highest performance QuadraTherm inline air flow meter with accuracy +/- 0.75% of reading, to our more traditional, and also very accurate, 600 Series mass flow meters.

For increased field flexibility and precision, our QuadraTherm immersible thermal meters offer:

  • Capability to change pipe size (Dial-A-Pipe) in the field
  • Field validation with easy in-situ calibration
  • Lifetime warranty on patented, no drift DrySense sensor
  • qMix gas mixing software to create and upload new gases to your meter when gas composition changes, all without sending the meter back to the factory for recalibration

For easy systems integration with our flow meters, we offer the following digital communications solutions HART, Modbus RTU, Profibus DP, and Foundation Fieldbus.

Capillary Thermal

Our digital capillary thermal flow meters are ideal for scientific applications with flows up to 1000 slpm, such as research, automotive, biopharm, aerospace, and manufacturing. Find your in line air flow meter by flow application.

The SmartTrak series, our flagship capillary thermal line of inline digital air flow meters, includes:

  • Mass flow rates up to 1000 slpm (nlpm); higher upon request
  • Dial-A-Gas technology to easily switch between 10 pre-programmed gases
  • Easy set-up and use with user-friendly navigation and software
  • Inherently linear laminar flow element (LFE) design
  • Standard accuracy: +/- 1.0% of full scale Repeatability: +/- 0.2% of full scale

Digital Air Flow Meter FAQ

Q: How should air flow be measured?

A: Air flow, including compressed air measurement, hit the top of the list for “killer apps” that almost every facility must measure and manage. Many facilities use air and compressed air in manufacturing, food production, and heavy industrial applications. Facilities may require tracking of gas distribution, allocation, and billing.

Thermal mass flow meters are ideal for air flow measurement applications because mass flow rate, not volumetric, is the quantity of direct interest. In a thermal flow meter’s simplest working configuration, fluid flows past a heated thermal sensor and a temperature sensor. As the molecules of the fluid flow pass the heated thermal sensor, heat is lost to the flowing fluid. The thermal sensor cools down, while the temperature sensor continues to measures the relatively constant temperature of the flowing fluid.

The amount of heat lost depends on the thermal properties of the fluid and the flow rate of the fluid. Thus, by measuring the temperature difference between the thermal and temperature sensors, the air flow rate can be determined.

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