Monthly Archive: February 2007

Feb
28

Setpoint Rate Limiting in Control

Many control systems have traditionally provided some capability to limit the rate of change in a setpoint value used in control. When a setpoint change exceeds this rate of change limit, then the rate limited value is use in control. Thus, the full setpoint change is not immediately seen in control until the rate limited …

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Feb
27

Stirring it Up

If you ever wondered if you are agitated enough, then this blog may help stir up some thoughts. Specifically, how does the relative type and degree of mixing in the plant design affect your job as an automation professional? If the process engineer tells you the project is installing a radial instead of an axial …

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Feb
19

So Many Models, So Little Time

My favorite “Far Side” cartoon has Einstein at a chalk board full of derived equations ending up with the ultimate equation “time=money.” In my mind, the negative free time of the process control engineer places some doubt as to whether this endangered species still exists. There have been sightings but the uncertainty principal says we …

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Feb
12

Missing in Action

Where have all the instrument and process control engineers gone? Are they in Florida enjoying golf and the weather, are they filling in part time for a contract engineering design job oblivious to the ice or snow storm, or are they like me venting into the blog sphere? It is easy for plants to forget …

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Feb
12

Reducing Batch Cycle Time

The control design and commissioning of a continuous process often focuses on the requirements associated with operating conditions found at normal plant throughput. Thus, during the startup of the process, many controls are left in manual and it is up to the operator to get the process to the point where the controls can be …

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Feb
05

Development of Adaptive Control Technology

When we first started Emerson’s advanced control program in the early 90’s, one of the initial objectives of the program was to develop an adaptive control capability that could be used in our control products. However, we realize that adaptive control is one of the most challenging advanced control areas to address from a technical …

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Feb
05

A Head Start in Practical Process Control

The students at Washington University in Saint Louis are ahead of the curve by virtue of the efforts of affiliate professors Terry Tolliver and Robert Heider who have a combined total of more than 65 years of industrial experience at Monsanto and Solutia. Terry Tolliver teaches a process control course for junior and senior chemical …

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