Flow rate control device, and diagnostic device and recording medium recorded with diagnostic program used for flow rate control device

A diagnostic device for use in a flow rate control device comprising:

• a first flow rate measuring mechanism configured to measure a flow rate of fluid flowing through a flow channel;
• a flow rate control valve provided on the flow channel;
• and a valve control part configured to control an opening degree of the flow rate control valve so as to reduce an error between a target flow rate value and a first measured flow rate value measured by the first flow rate measuring mechanism, the diagnostic device comprising:
• a fluid measuring mechanism configured to measure a flow rate or a pressure of the fluid flowing through the flow channel;
• a first measured flow rate diagnostic part is configured to diagnose an abnormality of the first measured flow rate value, based on a second measured flow rate value or a measured pressure value measured by the fluid measuring mechanism;
• and
• a valve diagnostic part configured to diagnose an abnormality of the flow rate control valve, based on an opening level control parameter that is inputted to the flow rate control valve by the valve control part, a supply pressure value that is a pressure measured on an upstream side of the flow rate control valve, and at least one of the first measured flow rate value, the second measured flow rate value, and the measured pressure value, when the first measured flow rate diagnostic part diagnoses that the first measured flow rate value has no abnormality.

A diagnostic program for use in a flow rate control device comprising:

• a first flow rate measuring mechanism configured to measure a flow rate of fluid flowing through a flow channel;
• a flow rate control valve provided on the flow channel;
• a valve control part configured to control an opening degree of the flow rate control valve so as to reduce an error between a target flow rate value and a first measured flow rate value measured by the first flow rate measuring mechanism;
• a fluid measuring mechanism configured to measure a flow rate or a pressure of the fluid flowing through the flow channel, the diagnostic program comprising:
• a first measured flow rate diagnostic part is configured to diagnose an abnormality of the first measured flow rate value, based on a second measured flow rate value or a measured pressure value measured by the fluid measuring mechanism;
• and
• a valve diagnostic part configured to diagnose an abnormality of the flow rate control valve, based on an opening level control parameter that is inputted to the flow rate control valve by the valve control part, a supply pressure value that is a pressure measured on an upstream side of the flow rate control valve, and at least one of the first measured flow rate value, the second measured flow rate value, and the measured pressure value, when the first measured flow rate diagnostic part diagnoses that the first measured flow rate value has no abnormality.