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Sierra's QuadraTherm® 640i/780i Wins Industry Award

QuadraTherm takes Gold Award in Gases & Instrumentation® 2013 Golden Gas Awards

MONTEREY, CA — March 25, 2013 — Sierra Instruments is pleased to announce that their new product, the QuadraTherm® 640i/780i flow meter is the Gold Winner for  Gases and Instrumentation’s 2013 Golden Gas Awards for innovation in gas flow measurement and control.  The innovation in the QuadraTherm 640i/780i marks a disruptive breakthrough in thermal dispersion technology offering customers in process control industries unprecedented accuracies of +/- 0.5% of reading about 50% of full scale (air). Before QuadraTherm, this level of accuracy was never thought possible with thermal dispersion mass flow meters.

The innovation in the patented QuadraTherm four-sensor technology provides the critical inputs to achieve +/- 0.5% accuracy. In the traditional “two-sensor” flow meter, the heat lost via stem conduction is not accounted for. This can introduce errors as high as 20 percent, depending on the gradient between the gas temperature and the temperature outside of the pipe. The new “four-sensor” design solves this problem by adding two more sensors to the traditional flow sensor, offering customers higher accuracy, competing with the accuracy of Coriolis meters at a fraction of the installed cost.

“We are very pleased that years of hard work and innovation have been recognized, but what we are most proud of is that the QuadraTherm 640i/780i mass flowmeter offers our customers greater accuracy and efficiency than ever thought possible with thermal dispersion technology.  This truly marks a turning point in thermal dispersion technology which will reshape customers’ expectations about performance and accuracy specs for thermal measurement instrumentation,” says Erica Giannini, Director of Marketing at Sierra instruments.

Along with this four-sensor innovation, QuadraTherm Technology moves from the traditional Wheatstone bridge circuit to a powerful microprocessor that runs a comprehensive flow-measurement algorithm called qtherm®, the “brain” of the instrument. This algorithm uses the dry sensor technology and inputs from the four temperature sensors to solve the first law of thermodynamics in a fraction of a second for each mass flow meter data point. This allows the QuadraTherm 640i/780i to manage changes in:

• Gas mass flow rate

• Gas temperature

• Gas pressure

• Outside temperature

• Pipe conditions (size and roughness)

• Flow profile

The QuadraTherm Series also has multivariable outputs (mass flow, temperature, and pressure), measures all non-condensing clean gases, and features ValidCal™ Diagnostics to validate calibration in the field.

Summary of Key Features

• Accuracy: +/- 0.5% of Reading

• Flow ranges up to 60,000 sfpm (305 smps)

• Multivariable: Mass flow rate, T, and P

• QuadraTherm® four-sensor design

• DrySense™ no-drift sensor with lifetime warranty

• qtherm® “Brain” manages changes in gas, T, P, Outside Temp

• Dial-A-Pipe®: Change pipe size


Learn more about QuadraTherm today



A global leader in flow measurement and control for over 40 years, Sierra instruments designs and manufactures high performance flow instrumentation for gas, liquid and steam applications commonly found in the pharmaceutical, scientific research, health, energy and semi-conductor industries. With over 150 offices in 50 countries, Sierra is uniquely positioned to provide their innovative products and lifetime support for the leading companies of today and the growth enterprises of tomorrow.


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