Introduction of SCADA, Architecture of SCADA, Software and hardware architecture, Components of a SCADA system, Functions of SCADA, Alarms and events, alarm logging, comparision between scada and DCS

1. SCADA
Presented by,
PRAVEENKUMAR S-15E137
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2. Overview of SCADA
• A SCADA (Supervisory Control and Data Acquisition) is an industrial
computer-based control system used to acquire the real-time data
to keep track, monitor and control industrial equipments at the
supervisory level.
• It is a combination of software, hardware and protocols.
• It is used in different types of industries
and various domains.
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3. Purpose of SCADA
• Ability to collect data & control process from distance.
• Ability to create logs on system’s current and past state
• Ability to send necessary information to operators in real time using SMS
and internet.
• Reduces man-power needs
• Saves Energy, Time and Money
• Less traveling for workers
• Reliable
• Supervisory control over a particular system
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4. Overall functions 4

5. DOMAINS
• Electrical generation, transmission & distribution
• Automation
• Railway and transportation
• Chemical storage and transportation
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6. History
• Before the concept of SCADA, industrial plants and remote sites
relied on personnel to manually control and monitor equipment
via push buttons and analog dials.
• Industrial organizations started to utilize relays and timers to
provide some level of supervisory control without having to send
people to remote locations to interact with each device.
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7. 4 Types of SCADA systems
• First Generation: Monolithic or Early SCADA systems(1950-70),
• Second Generation: Distributed SCADA systems(1980-90),
• Third Generation: Networked SCADA systems(1990-2000) and
• Fourth Generation: Internet of things technology, SCADA
systems(2000)
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8. Monolithic or Early SCADA Systems
• Minicomputers are used earlier for computing the SCADA systems.
In earlier times, the common network services were not available.
Hence, these are independent systems without having any
connectivity to other systems.
• The functions in the early first generation were limited to
monitoring sensors in the system and flagging any operations in
case of surpassing programmed alarm levels.
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9. Distributed SCADA Systems
• The sharing of control functions is distributed across the multiple
systems connected to each other using Local Area Network (LAN).
• These individual stations were used to share real-time information for
performing control tasks to trip the alarm levels of possible problems.
• The cost and size of the station were reduced compared to the first
generation system, as each system of the second generation was
responsible for performing a particular task with reduced size and cost.
• But even in the second generation systems also the network protocols
were not standardized(proprietary).
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10. GEN 2 VS GEN 3 10
• The first and second generation SCADA systems are limited to single site networks called as sealed
systems.
• In these systems, we can not have any risk compared to the third generation SCADA system which are
connected to the internet causing the security risks.
• There will be several parallel working distributed SCADA systems under a single supervisor in network
architecture.

11. Networked SCADA Systems
• The current SCADA systems are generally networked
and communicate using Wide Area Network (WAN) Systems over
mobile network, Ethernet or Fiber Optic Connections for
transmitting data between the nodes frequently.
• These SCADA systems use Programmable Logic Controllers (PLC)
for monitoring and adjusting the system parameters.
• Open system architecture and communication protocols
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12. Architecture of SCADA
• Generally the SCADA system includes the following components:
local processors, operating equipment, PLCs, instruments, RTU,
intelligent electronic device, master terminal unit or host
computers and a PC with human machine interface.
• Clint layer
• Data server layer
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13. Hardware 13

14. Software architecture
• Most of the servers are used for multitasking and real time
database. The servers are responsible for data gathering and
handling.
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15. SCADA Basics
• The block diagram of SCADA system
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16. Human-machine Interface (HMI)
• It is an i-o device that presents the data to be controlled by a
human operator.
• It is used by linking to the SCADA system’s software programs for
providing the information, including the scheduled maintenance
procedures, detailed schematics, trending and diagnostic data for
a specific sensor or machine.
• HMI systems facilitate the operating personnel to see the
information graphically.
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17. Supervisory System
• Supervisory system is used as server for communicating between
the equipment of the SCADA system such as RTUs, PLCs and
sensors, etc., and the HMI software used in the control room
workstations.
• Master station comprises a single PC in smaller SCADA systems
and, in case of larger SCADA systems, it comprises distributed
software applications, disaster recovery sites and multiple
servers.
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19. Remote Terminal Units
• Physical objects in the SCADA systems are interfaced with the
microprocessor controlled electronic devices called as Remote
Terminal Units (RTUs).
• These units are used to transmit telemetry data to the supervisory
system and receive the messages from the master system for
controlling the connected objects.
• Data logging and alarm handling
• Asks the field devices for information
• Can control IEDs (Intelligent Electronic Device)
• Slave/Master device
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20. Programmable Logic Controllers
• In SCADA systems, PLCs are connected to the sensors for collecting
the sensor output signals in order to convert the sensor signals
into digital data. PLCs are used instead of RTUs because of the
advantages of PLCs like flexibility, configuration, versatile and
affordability compared to RTUs.
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21. Communication Infrastructure
• Generally the combination of radio and direct wired connections is
used for SCADA systems, but in case of large systems like power
stations and railways wireless network are frequently used.
• Private Network (LAN/RS-485)
• Internet
• Wireless Communication systems
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22. Communication protocols
• MODBUS
• DNP 3.0
• Fieldbus
• Controller Area Network (CAN)
• Profibus
• DirectNet
• TCP/IP
• Ethernet
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23. SCADA Server
• It can be a Web server
• Data logging
• Analyzing data
• Serve the clients through a firewall
• Clients connected through internet
• Real-time decision maker
• Asks RTU for information
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24. SCADA Programming
• SCADA programming in a master or HMI is used for creating graphs
and diagrams which will give an important situational information
in case of an event failure or process failure.
• SCADA programming can be done using derived programming
language or C language
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25. Event and alarm
• An alarm is an indication of an undesirable condition detected by
the system such as a device that is not responding to input
commands. The alarm alerts operators that this condition needs to
be fixed.
• Event is a detectable occurrence which is of significance to the
change of SCADA.
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26. Monitoring and Event Processing 26

27. Alarm logging 27
Alarm logging provides
a straightforward process
for creating and
maintaining records to
analyze the alarm state
of equipment and
processes.in your
system.

28. Conclusion
SCADA is a control system with
• More front end functionality
• More interfaces and efficient storage
• More record or device oriented configuration but System wide
configuration tools are needed
• Less expensive than DCS, but offer different functionality than
DCS And finally various applications
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29. THANK YOU..!! 29