Link:http://output.to/sideway/default.asp?qno=100100001

Process Control

 A process can be represented by a block diagram.

Inputs can be divided into manipulated or disturbance inputs.

Outputs can be divided into measured or unmeasured outputs.

For a simple process control or automation, the process output or the disturbance input are measured by sensors and they are used to determine the proper manipulated input by the controller.