Consider the liquid-level control system shown in Figure 4-43. The controller is of the proportional type. The set point of the controller is fixed. Draw a block diagram of the system, assuming that changes in the variables are small. Obtain the transfer function between the level of the second tank and the disturbance input qd. Obtain the steady-state error when the disturbance qd is a unit-step function.
Figure 4-43
