What Is It
SCADA is acronym for Supervisory Control and Data Acquisition. It is a kind of software application program used for process control and gather real time data from remote locations for exercising this control on equipments and conditions.
Components
The SCADA System consists of hardware and software components. The hardware collects and feeds data into a computer with SCADA software installed. The data is then processed by the computer before presenting it in a timely manner. The function of SCADA is recording and logging all events in a file that is stored in a hard disk or sending them to a printer. If conditions become hazardous, SCADA sounds warning alarm.
Use
SCADA finds use in power plants, oil and gas refining, transportation, telecommunication, various treatment plants and in control of waste and water. Typical use of SCADA system is data collection and control at the supervisory level. Data acquisition without control is not SCADA.
The Processes
The processes are in the domain of industrial, infrastructural and facilities. Industrial processes like manufacturing, fabrication, refining, etc. may be in batch or continuous, discrete or repetitive. The processes used in infrastructure like power transmission, communication, water treatment, etc. may be either public or private. Public or private facility processes involve monitoring and controlling of access and managing energy consumption in airports, buildings, space station, etc.
Supervisory Control
SCADA system is basically measurement and control system. The control after data collection is done at the supervisory level. The measurement and control is done in a large scale in any size or geographical distribution. SCADA is not a real time control but is placed in addition to real time control for controlling processes external to SCADA. A real time control like control of power consumption by a computer itself is integrated and SCADA in spite of collecting real time data from remote locations is not a real time control system in that sense.