Monthly Archive: September 2008

Sep
26

Tips-N-Techniques (TNT) – Reset Has No Sense of Direction

We live in a digital world but don’t stare at digital values of process variables. If a reactor temperature is below set point as shown in the Good Tuning Pocket Guide Figure 2 for a PID loop faceplate, should the steam or water valve be open? After looking at a faceplate or the digital value …

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Sep
20

Tips-N-Techniques (TNT) – Resetting Reset Time

A couple of rules of thumb come to mind from tuning loops over the last 40 years for the chemical process industry on how you might want to reset the reset time. The Lambda tuning rule reveals the nature of the problem people get into for loops with vastly different speeds of response. Per Lambda …

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Sep
05

Gone Fishin – Back Sept 18