Kc = 1.25, Ti = 30 minutes
Level, %
90
80
70
60
50
40
30
20
10
Flow Rate, %
80
70
60
50
40
30
20
10
0
70
60
50
40
30
20
10
0
–10
Level, %
Flow In
Flow Out
Time, minutes
Figure 9.9 Level control response to setpoint change.
Kc = 1.25, Ti = 10 minutes
Level, %
90
80
70
60
50
40
30
20
10
Flow Rate, %
80
70
60
50
40
30
20
10
0
Level, %
Flow In
Flow Out
–10
0
10
20
30
40
50
60
70
Time, minutes
Figure 9.10 Level response to load change.
Closed-Loop Tuning of Controllers ◾  101