Mar
25
One of the most common ways of addressing multiple process inputs is split range control. A splitter block, which appears as one valve to the PID block, can be used in the control strategy to define a fixed relationship between the controller output and each manipulated process input. In Advanced Control Foundation – Tools, Techniques, …
Mar
18
From a control perspective, it is highly desirable that the process gain is constant. If the process gain is constant, then the same proportional gain can be used over the entire operating range of the control loop. Using a control valve as an example, if the valve characteristic was not properly selected based on the …
Mar
11
When a control loop is placed in automatic control, it is easy to detect if a valve or actuator is not responding correctly to the control system. As discussed in Chapter 3 of Advanced Control Foundation – Tools, Techniques and Application, this can be done by observing the response of the controlled parameter to control …
Dec
10
The single loop and multi-loop control techniques most often used in automating continuous and batch processes are addressed in the book Control Loop Foundation – Batch and Continuous Processes. Similarly, the advanced control techniques that are most often utilized in the process industry are addressed in the book Advanced Control Foundation – Tools, Techniques, and …
Sep
17
I worked closely with Emerson’s education department to establish the class Control Loop Foundation (9025). This 4 ½ day class is intended primarily for people who are new to the process industry and process control. Approximately 30% of the class is dedicated to workshops in which the students get hands on experience working with the …
Aug
20
IEC accepted the U.S. National Committee’s offer to hold IEC/TC 65, SC 65A, SC 65B, SC 65C and SC 65E meetings during the weeks of 17-21 and 24-28 September 2012 at the Orange County Convention Center, Orlando Florida, USA. Subcommittee meetings are schedules the week before the start of ISA Automation Week. The plenary will …
Jul
30
Courses required for an engineering degree are designed to provide the student with a sound technical foundation for work in industry. However, in most cases these courses do not address the terminology and common practices that an engineer must know to design, implement, checkout and commission a process control system. Universities can help bridge this …
Jun
04
It was my pleasure to co-teach with Darrell Dray the Control Loop Foundation class (9025) the week of May 21st, 2012. The class was held in Emerson Process Management’s Education Center located in Round Rock, TX – just outside of Austin, TX. This 4 ½ day class is based on the Control Loop Foundation book. …
Jan
26
A compressor going into stall is like jumping off a cliff with a bungee cord. If the bungee cord has no losses to dampen the oscillation, we have something akin to surge. A 0.5% drop in efficiency can occur for each surge cycle. Several surge cycles can occur due to delays and lags in high …
Dec
19
As addressed in my December 12th blog posting, James Beall and I presented Part 1 of this presentation on Friday morning at Emerson Exchange, 2011 in a “meet the expert” workshop. Part 2 was not presentation at Emerson Exchange because of time limitation. In this continuation of the presentation we address when it is possible …
