Thermal measures of mass flow

QuadraTherm® 640i

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

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

Backed by lifetime sensor warranty

Boiler MACT certified for area source boilers and for major source boilers

Part of Sierra’s Big-3 iSeries family of flow meter technologies