Process Controls
CONTROL LOOP DIAGRAMS
Constant amplitude (Figure 10B). Action of the controller sustains oscillations of the controlled
variable. The controlled variable will never reach a stable condition; therefore, this condition is
not desired.
Increasing amplitude (Figure 10C). The control system not only sustains oscillations but also
increases them. The control element has reached its full travel limits and causes the process to
go out of control.
Rev. 0
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IC-07
