Sierra QuadraTherm® 640i Thermal Insertion Mass Flowmeter for Air/ Gas


The QuadraTherm® 640i is the most accurate insertion-probe thermal mass flow meter for air / gas mass flow rate measurement on the market today, achieving gas mass flow rate accuracy never before possible, +/- 0.75% of reading above 50% of full scale. The QuadraTherm 640i air / gas mass flow meter marks an accuracy breakthrough in thermal dispersion technology achieving extreme precision with “percent of reading” accuracy, which for the first time rivals accuracies of Coriolis technology for measuring mass air flow rate and other gases.
- Achieve high accuracy +/- 0.75% of reading
- Eliminate drift with patented DrySense™ sensor
- Validate in the field for easy in-situ calibration
- Use qMix software to easily change gas composition in the field and retain accuracy Download Flare Gas Mass Measuring Tech Note
- Backed by lifetime sensor warranty
- Boiler MACT certified for area source boilers (40 CFR 63, subpart JJJJJJ) and for major source boilers (40 CFR 63, subpart DDDDD)
- Part of Sierra’s Big-3 iSeries family of flow meter technologies
- Meet EPA rule 40 CFR 63 for flare gas measurement at ultra-low flows down sfps (0.03 smps) with QuadraTherm® qMix RealTime Flare Measurement System (FMS)
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