Patent ID: 7693606

Claim:
A flow control system comprising: a flow sensor configured to generate a sensor signal characterizing a flow rate; a valve controller configured to control the flow rate as a function of a control output; a signal processor configured to convert the sensor signal into a flow signal characterizing the flow rate as a function of time; a control processor configured to generate the control output as a function of a setpoint and the flow signal; and an interface configured to receive an input representative of the setpoint and to transmit a flow output representative of the flow signal, flow diagnostic indicative of an operational condition of the flow control system and a control diagnostic indicative of an operational condition of the flow controller: wherein the flow diagnostic is based on an inverse signal-to-noise ratio of a standard deviation of the flow signal to a mean of the flow signal, and the control diagnostic is based on a response function relating the control output to at least one of the setpoint and the flow signal.