FIGURE 10.1 Typical physical appearance of a controller. Curtis Johnson Process Control Instrumentation Technology, 8e] Copyright ©2006 by Pearson Education,

FIGURE 10.1 Typical physical appearance of a controller.

Curtis JohnsonProcess Control Instrumentation Technology, 8e]

FIGURE 10.2 Error detection for systems using a floating power supply.

FIGURE 10.3 Error detector using a ground-based current and a differential amplifier.

FIGURE 10.4 A mercury switch on a bimetal strip is often used as a two-position temperature controller.

FIGURE 10.5 A two-position controller with neutral zone made from op amps and a comparator.

FIGURE 10.6 The circuit of FIGURE 10.5 shows the characteristic two-position response in terms of voltage.

FIGURE 10.7 An op amp proportional-mode controller.

FIGURE 10.8 An op amp integral-mode controller.

FIGURE 10.9 A practical derivative-mode op amp controller.

FIGURE 10.10 An op amp proportional-integral (PI) mode controller.

FIGURE 10.11 An op amp proportional-derivative (PD) mode controller.

FIGURE 10.12 Direct implementation of a three-mode (PID) controller with op amps. Circuits with fewer op amps are often used.

FIGURE 10.13 The pneumatic proportional-mode controller.

FIGURE 10.14 Pneumatic proportional-integral controller.

FIGURE 10.15 Pneumatic proportional-derivative controller.

FIGURE 10.16 Pneumatic three-mode (PID) controller.

FIGURE 10.17 Circuit for Example 10.11.

FIGURE 10.20 System for Problem 10.6.

FIGURE 10.21 System for Problem S10.1.

FIGURE 10.22 Nozzle/flapper characteristic for Problem S10.2.

Documents