SCADA is a system for supervisory, control, and data acquisition in industrial systems with the display of parameters, where the availability and reliability of this system stands at very high level. Every process in the industry, that makes sense to automate, is a great candidate for the implementation of SCADA systems and networks. These systems include a wide range of equipment, subsystems and technical solutions that enable the data acquisition and processing, as well as appropriate reactions, in different remote systems and processes. Process management, in general, may be automatic or initiated by the operator.
In the field of water treatment systems can be used for simple monitoring of water flow, pressure, chlorine residual, to the very complex monitoring and control of technological processes of water disinfection.
One of the main features of the SCADA system is the centralization of the priority functions on supervisory control unit. Actually, the software support in remote stations ensures data acquisition and local process management to a level that is defined from the central station, but the initiation of all control functions and final verification of their execution is carried out in central station. On this station are defined and transmitted reference signals, formulations are entered, functions of individual subsystems are synchronized and determined reactions to specific alarms, optimization of algorithms is performed, etc. All data are stored in a database from where their presentation is performed as well as generation of control actions.
Communication between remote stations and central station, and between individual central stations, is performed through the certain communication medium, depending on the possibilities and demands of user. For data transfer is used one of the standard or specialized media such as Ethernet, Modbus, Profinet and so on, thus ensuring the transfer of information between remote stations and command center. Optical cables are ideal for implementation of SCADA networks because they can offer complete protection against a variety of radiations and other external influences that could lead to transmission of incorrect information.
SCADA systems are widely used in different business systems and areas, wherever is necessary to monitor and control a large number of processes. Examples of application can be found in electric power systems, water management, industrial complexes, production, traffic and transportation, and so on. The structure and architecture of SCADA system depends on the specific process and requirements of the real business system.