Question 3. A pumping station is used to pump water from a nearby river to a covered storage tank for use on a farm. The tank should be kept full

so that water is available for the irrigation system on the farm. Another pump is then required to pressurise the irrigation system using water from the tank when required. (a) (10 marks) On the next page, sketch a P&ID for a feedback controller that willmaintain a high level in the tank and allow for water to be used for irrigation ondemand. The following icons may be useful to use when drawing the P&ID: (b) (8 marks) There are two situations on the farm that could cause damage to the pumps.If the pressure on the suction side of either pump is too low, cavitation in the pump can occur. In addition, if the irrigation system is blocked, the pressure can build in the pipework and cause damage and leakage in the irrigation pipework. On the next page,draw a P&ID showing a system to protect the pumps and irrigation system from damage due to these two events. (c) (5 marks) A PID controller is used for the level controller on the tank. Discuss what can happen to the integral action of the controller if override control in implemented.What can be done to avoid problems with integral control in an override control situation?