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How Do I Calculate Gain? What Is the Difference Between Process Gain and Controller Gain?
Among practitioners who tune PID control loops manually most note their focus on calculating the Gain. Process Gain is a model parameter whereas Controller Gain is a tuning parameter. The former describes important aspects of a given process’ dynamic behavior. The later contributes to the PID controller’s responsiveness to disturbances.
What Are the Pros and Cons of the Step Test?
Face it, more often than not tuning a PID controller is usually easier when software is applied. While not all products are created equal, the modeling capabilities within most commercial controller tuning software products can account for dynamics that are often overlooked by the human eye. Noisy and oscillatory data can thwart even the most experienced among us. So what should a practitioner do when the use of tuning software isn’t an option? The answer: Perform a step test.
How Do I Tune a Level Controller?
Level controllers present challenges that are different from others. Although their presence is significant they lag behind Flow controllers in their overall share of the typical production facility’s process control landscape. Unlike other processes such as Temperature, Pressure and Flow, Level control loops demonstrate different dynamics, they don’t play by the same rules as the non-integrating (also known as self-regulating) types. And although best-practices for modeling and tuning Level loops are similar they involve nuances that can hamper a less experienced practitioner.
Why is Zeigler-Nichols the Wrong Choice for Your PID Controllers?
In 1909 Henry Ford famously offered customers any color of his Model T automobile as long as their choice was black. Ford’s “one size fits all” philosophy worked remarkably well at the turn of the 20th Century. For sure, the general population’s improved financial means, its appetite for mobility, and of course a dearth of alternative low-cost options played a role. In contrast, a “one size fits all” approach to PID controller tuning doesn’t work so well in today’s complex, multi-process production environments