Preview only show first 10 pages with watermark. For full document please download

Pid Control Book 2nd John A. Shaw Is A Process Control Engineer And President Of Process Control Solutions. An Engineering Graduate Of N. C. State University, He Previously Worked For Duke Power Company In Charlotte, N. C. And For Taylor Instrument Company (now Part Of Abb, Inc.) In, N. Y. Rochester He Is The Author Of Over 20 Articles And Papers And Continues To Live In Rochester. Copyright 2003, John A. Shaw, All Rights Reserved. This Work May Not Be Resold, Either Electronically Or On Paper. Permission Is Given, However, For This Work To Be Distributed, On Paper Or In Digital Format, To Students In A Class As Long As This Copyright Notice Is Included.

Description: Process control is the measurement of a process variable, the comparison of that variables with its respective set point, and the manipulation of the process in a way that will hold the variable at...

   EMBED

Share

Transcript

Process control is the measurement of a process variable, the comparison of that variables with its respective set point, and the manipulation of the process in a way that will hold the variable at its set point when the set point changes or when a disturbance changes the process. An example is shown in Figure 1. In this example, the temperature of the heated water leaving the heat exchanger is to be held at its set point by manipulating the flow of steam to the exchanger using the steam flow valve. In this example, the temperature is known as the measured or controlled variable and the steam flow (or the position of the steam valve) is the manipulated variable.