Patent ID: 8793082

Claim:
An upstream mass flow verification system for testing the performance of a mass flow controller, the system comprising: an upstream volume capable of storing a test fluid, wherein the upstream volume is upstream of a mass flow controller, wherein the mass flow controller is under test and has a given dead volume; a temperature sensor configured to sense the temperature within the upstream volume; a pressure sensor configured to sense the fluid pressure within the upstream volume; and a processor configured to receive temperature and pressure signals from the temperate sensor and pressure sensors, respectively, and to calculate the flow rate of test fluid through the mass flow controller based on the received temperature and pressure signals and which compensates for errors caused by the given dead volume within the mass controller; wherein the processor is configured to, in calculating the flow rate of test fluid through the mass flow controller, compensate for the given dead volume for either of (i) the case where the mass flow controller is pressure-insensitive, or (ii) the case where the mass flow controller is pressure-sensitive.