In most systems there are locations where operations, must be done from time to time and under specified norms and constraints in accordance with a directed action , but the cost of providing and maintaining an operator attendance all the 24 hours in a day can’t be justified.
The manual process works well for small networks but consumes time, labours and efficiency in large networks & also decreases reliability levels.
SCADA operates as a stand alone, autonomous system, monitoring sensors, displaying data, outputting controls, activating alarms and logging information to facilitate and optimize the plant processes and on-going operations
The Human-Machine Interface is a interaction among human & machine to monitor and to control multiple remote controllers, PLC’s and other control devices.
An HMI also linked to a database, to provide trending, diagnostic data, and management information such as scheduled maintenance procedures, logistic information, detailed schematics for a particular sensor or machine, and expert-system troubleshooting guides.
The SCADA systems established are playing a vital role in displaying the exact rate at the appropriate time, reliability level and helping a lot in reducing the risks and restoring normalcy in grid in case of occurrence of sudden disturbances.