Hach EC1000, Instruction Manual

Page: 53 / 128

53
Figure 10 PID pH Process Gain
Figure 11 PID Titration Curve
10 20
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2
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14
30 40 50 60 70 80 90 100
REAGENT DEMAND %
pH
Setpoint
1
2
3
4
5
The process gain seen by the controller is the slope of a line between
the setpoint and the pH measurement on the titration curve.
16
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1
0
-1
-2
0 20 40 60 80 100
pH
REAGENT DEMAND %