How well a loop performs depends upon the tuning. A slowly tuned loop will do as poorly as a loop with bad dynamics. Thus, money spent to improve loop dynamics by making valves and measurement faster or the delay in the process response smaller is wasted unless the controller is tuned for a reasonably fast response.
In this chapter, simple relationships are developed to show how tuning settings affect the ability of the loop to correct for unmeasured load responses to maximize process efficiency and capacity and reach setpoints faster to minimize batch cycle time and continuous system transition time. Guidance is also offered on how to eliminate setpoint overshoot while still achieving these other ...