SCADA is a control system architecture comprising computers, networked data communications and graphical user interfaces for high-level supervision of machines and processes. It also covers sensors and other devices, such as programmable logic controllers, which interface with process plant or machinery.
Example of SCADA used in office environment to remotely monitor a process
The United States Army's Training Manual 5-601 covers "SCADA Systems for C4ISR Facilities"
A control system manages, commands, directs, or regulates the behavior of other devices or systems using control loops. It can range from a single home heating controller using a thermostat controlling a domestic boiler to large industrial control systems which are used for controlling processes or machines. The control systems are designed via control engineering process.
The centrifugal governor is an early proportional control mechanism.
An electromechanical timer, normally used for open-loop control based purely on a timing sequence, with no feedback from the process
Example of a single industrial control loop; showing continuously modulated control of process flow.
A DCS control room where large screens display plant information. The operators can view and control any part of the process from their computer screens, whilst retaining a plant overview on the larger screens.
