Chapter 8

PID Feedback
Control Loop

This chapter provides an introduction to a feedback process
control loop and a description of the action provided by
Proportional (P), Integral (I), and Derivative (D).
Learning Objectives
When you have completed this chapter, you should be able to
1. Understand the concept of the process variable, the controller setpoint, and the error between them
2. Understand the controller action provided by the proportional gain (P)
3. Understand the controller action provided by the integral
(I) reset
4. Understand the controller action provided by the derivative (D) rate or preact
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