For a liquid-level control system similar to that in Fig.
Chapter 11, Problem 11.6(choose chapter or problem)
For a liquid-level control system similar to that in Fig. 11.22, Appelpolscher has argued that integral control action is not required because the process acts as an integrator ( cf. Eq. 11-77). To evaluate his assertion, determine whether proportional-only control will eliminate offset for step changes in (a) set point and (b) disturbance variable.
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