The FMA7400/7500 (elastomer seal) and (-SS) (metal seal) Series thermal-mass flowmeters and controllers overcome the limitation of many thermal-mass flow units when changing gas types, a simple correction factor, such as the ratio of heat capacities between the calibration gas and new gas, can’t account for accuracy, robbing viscosity and density differences.
The unit’s database is built on thousands of native gas runs to establish correction functions that account for both thermal and physical differences among gases.
The Series features a corrosion-resistant Hastelloy C-22 sensor for long-term operation. Settling time is less than a second and full scale accuracy is 1%. Both versions achieve internal to external leak integrity for challenging process gases as found in CVD, solar, and other processes.
Specifications include 3 sccm to 50 slm (depending on model number) full-scale flow range; flow accuracy of ±1% set-point 35 to 100%, ±0.35% full scale 2 to 35%, ±3% with selected gas feature; < 0.2% S.P. repeatability and reproducibility; ±0.5% full scale (included in accuracy) linearity; and <1 sec (within 2% for steps 0 to 10 through 0 to 100%) response (settling) time.
Omega Engineering Inc., One Omega Dr., Box 4047, Stamford, CT 06907, (888) 826-6342, www.omega.com