Requested White Paper
Using mass flow controller-based dynamic gas blenders to produce accurate calibration gas
Mass flow devices, developed in the 1960’s, are critical components is systems that produce the specialty gas standards required to calibrate a wide variety of instruments that analyze gases.
Mass flow devices generate a signal that is proportional to the mass flow of a gas. Since the specific heat of a gas is unique to a particular gas, mass flow devices are unaffected by pressure and temperature changes. Thus, the signal they generate is very accurate and stable.
If the signal voltage from a mass flow device is used to indicate flow, it is classified as a mass flowmeter (MFM). If the signal from such a device is used in conjunction with a reference signal and a controlling valve, it is classified as a mass flow controller (MFC).
When several MFC’s are operated in parallel, and are electronically controlled within tight limits, the gas mixtures produced are extremely accurate. This is the principle behind a commonly used gas mixing technique called “Dynamic Blending.”
