analogue control of a valve


Thread Starter


Can anyone suggest a typical electronic analogue control system that can be used to control the flow of air in a duct. The control system will control the pressure of the air by using pressure transducers then compare the actual pressure to a nominal value then use the error signal to drive the system and will probably employ an electrically actuated valve. There is also a requirement for the valve to be shut off if problems arise. I am assuming that the system will make use of differential amplifiers but I am currently trying to understand them. The system cannot make use of digital control only electronic analogue control. Thank you for taking time to read this request.

Steve Myres, PE

The normal device use for control of airflow in ductwork (I am assuming at normal static pressures of a few inches WG) is an opposed-blade damper. These can be fitted with many types of actuators, (pneumatic, electric, manual, electro-hydraulic, etc.) You might try Barber Colman (I think now a division of Siebe). They have many good products for sensing, controls, and actuators.
You can use normal pid controller. Input signal to pid controller will be from pressure transducer. Output will go to your electrically actuated valve. You can also use motorised damper actuaters.