Patent ID: 11971396
Assignee: VELTEK ASSOCIATES, INC.
Field: Measurement (Instruments)
Classification: CPC G  F  Y | IPC F  G

Claim 7:
8. The system of claim 7, wherein:
the plurality of air sampling devices comprises a first air sampling device and a second air sampling device;
the plurality of vacuum connections comprises a first vacuum connection configured to receive the volume of air from the first air sampling device and a second vacuum connection configured to receive the volume of air from the second air sampling device, the first and second vacuum connections in flow communication with a vacuum pump via a manifold;
the PLC is configured to reduce the difference between the measured flow rate of the volume of air received by the first vacuum connection and the setpoint indicative of the desired mass flow rate at the first air sampling device caused by a change in the volume of air through the second vacuum connection.