A mistake often made with operator displays is to limit the scope of the design work to mimic the process equipment shown on P&IDs and Process Flow Diagrams (PFDs). These initial displays include measurements, valves and final control elements. They include enough of the process equipment and piping so that the process flow can be …
Tag Archive: process
Feb
16
Control Classes – Dubai
In late November, 2014 I traveled to Dubai to teach the Control Loop Foundation class. This class is based on the book Control Loop Foundation – Batch and Continuous Processes and is a standard class offered by Emerson’s education department. In this class the students used the book’s web site to perform the workshops that …
Apr
14
IEC TC65 Standards Work
The international standards for industrial-process measurement, control and automation are developed through IEC TC65. As stated on the IEC web site, the standards developed by TC65 address systems and elements used for industrial-process measurement and control concerning continuous and batch processes. These standards address equipment and systems operating with electrical, pneumatic, hydraulic, mechanical or other …
Feb
17
High Speed Wireless Control
I was recently sent a link to a YouTube video of a control demonstration by professor Raffaello D’Andrea, The Institute for Dynamic Systems and Control at ETH, Swiss Federal Institute of Technology, Zurich. ETH is one of the world’s leading universities for technology and the natural sciences. I found the demonstration by Professor D’Andrea to …
Oct
28
Process Education on Demand
In Emerson’s boot camp for new engineers, I teach the portion on process control based on our book Control Loop Foundation – Batch and Continuous Processes. Each student receives a copy of this book. Customer may receive the same process control training by attending a 4 ½ day class, Control Loop Foundation – 9025, offered …
Aug
26
Neural Networks for Property Estimation
One of the key objectives of a process control system is to maintain product quality parameters within specifications. An on-line analyzer may not be available to make a sampled or continuous measurement of a physical property or the composition of a liquid or gas stream, or other conditions may prevent their use. In such a …
Aug
19
Fuzzy Logic Control – Example
In this fuzzy logic control workshop contained in Chapter 6 of Advanced Control Foundation – Tools, Techniques, and Applications, the control performance of fuzzy logic control is be compared to the performance of PID control. For this example, the control objective is to reach setpoint in minimum time with no overshoot. Two identical process heaters …
Aug
12
Fuzzy Logic Control – Commissioning
To allow consistent implementation of control applications, fuzzy logic control may be implemented as a function block. The fuzzy rules and membership functions can be predefined except for the scaling of the membership functions for error, change in error, and change in output. As addressed in Chapter 6 of Advanced Control Foundation – Tools, Techniques, …
Aug
05
Fuzzy Logic Control – Implementation
To minimize the time needed to apply fuzzy logic control, most manufacturers offer a version of fuzzy logic control in which the rules and membership functions are pre-defined. As described in Chapter 6 of Advanced Control Foundation – Tools, Techniques, and Applications, , a manufacturer can provide support for auto-tuning by restricting the fuzzy logic …
Jul
29
Fuzzy Logic Control
Fuzzy logic is a relatively new control technology. In the mid-1970s Mamdani began to investigate fuzzy logic as an alternative to the PID controller and sparked the first practical applications of fuzzy logic in the process control industry. The controller followed rules that generated an output by evaluating the error and the change in error. …
