What is Proportional-Only Control? When Should P-Only Control be Used?

By Control Guru | March 19, 2015

Place in Industrial Process Control.
As with most everything in process manufacturing, PID controllers require practitioners to make choices. One of those choices is which form of the controller to apply on a given regulatory control application. In a previous post the pros and cons of Derivative and the full PID were covered, and now the advantages and disadvantages of Proportional-Only control are explored. Due to performance characteristics the selection of a P-Only controller can be relatively straightforward and among a practitioner’s easier choices.

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What Sample Rate is Needed When Tuning PID Controllers?

By Control Guru | March 6, 2015

Practitioners often apply simple guidelines when it comes to data collection requirements and controller tuning. These “rules of thumb” assure that sufficient data resolution exists when a given PID control loop’s dynamics are being analyzed. Without good data a process engineer’s ability to model the dynamics and tune for improved control can be undermined. If the sample rate is too slow, then most any tuning procedure will be hit-or-miss at best. So what exactly are those guidelines?

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How Often Should PID Control Loops be Tuned?

By Control Guru | February 10, 2015

When it comes to PID control loops and the right time for tuning practitioners generally fall into one of two camps. There is the group that adheres to a philosophy whereby PID control loops should be tuned more or less every year. That’s that.  No debate. And there is another group that believes the answer for control loop tuning isn’t so cut and dried. From their perspective, it depends on the loop. It varies based on conditions. There is wisdom in both of these viewpoints.

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