B1.1 Reverse Acting Single Pid Control; Appendix B - ABB AX410 User Manual

APPENDIX B

B1 Single PID Controller – Fig. B1
The single PID controller is a basic feedback control system using three-term PID control with a local set point.
Manual Output
Control Set Point
Output 1
PID Control Loop
PID Output
Process Variable
Fig. B1 Single PID Controller
B1.1 Reverse Acting Single PID Control – Fig. B2
Reverse acting control is used when the process conductivity is less than the required output conductivity.
100%
Control
Output
Reverse
Acting
0%
0%
50% 100%
Process Variable Range
Fig. B2 Reverse Acting Single PID Control
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