Basics of SCADA ( Supervisory Control and Data Acquisition ) Advantages and Disadvantages


Whats SCADA ?

SCADA stands for Supervisory control and data acquisition.
SCADA is not a specific technology or protocol but refers to any application where data is
collected from a system in order to control that system

SCADA systems performs for functions
1.DATA acquisition
2.DATA communication
3.DATA presentation

Today SCADA systems are used for basically unattended monitoring and control of pipelines

water wastewater and utility grids. SCADA have the same capabilities as DCS systems really.
The biggest difference is that the DCS or distributed control system is inside the plant

well the SCADA system is outside.

The two basic components in the modern SCADA systems are RTU and the central station

computer. RTU stands for remote terminal unit and they have always been a smart and had as

much local control as they could be made to have.Different communication protocols are used

for the communication between RTU and Central Computer (Modbus ,Ethernet .)

The second major component of a SCADA system is central computer. SCADA has almost become synonymous with HMI even though the human machine interfaces just the window so to speak Behind the HMI is the database and the data historian and that means to connect the data to the enterprise.

Basics Components of SCADA
1.Sensors and controls elements - that interfaces directly with the system you managing
2.SCADA rtu - Remote telemetry units for fetching data from the sensors and delivering commands to control element
3.SCADA Master - serve as a central processor
4.Communication network - Connect the SCADA remote to master station

Advantages of SCADA systems

The SCADA systems data is used in maintenance and operations . Permit fewer employees to be

more productive.Remotely access the maintenance and operation data.
SCADA systems are regularly linked to asset management systems procurement systems billing
systems operation management systems throughout the HMI and the data historian .
SCADA systems are the major part of sustainability projects.
SCADA increases the efficiency of process
Reduces the maintenance cost

Disadvantages of SCADA systems
Chances of external interference (Hacking )