This document discusses supervisory control and data acquisition (SCADA) systems. It describes the typical hardware and software architectures of SCADA, including distributed databases, data servers, programmable logic controllers, and field buses. The document outlines common SCADA functions such as access control, human-machine interface, trending, alarm handling, logging, archiving, report generation, and automation. It also mentions SCADA development tools and data access mechanisms. In conclusion, the document states that SCADA systems offer more front-end functionality, efficient storage, and device-oriented configuration than distributed control systems.

1. SCADA
by
Prasad Mane (05IT6012)
School of Information Technology

2. Contents..
 Introduction
 Hardware Architecture
 Software Architecture
 Functionality
 Conclusion
 References
Jul 16, 2009 SCADA 2

3. Introduction
 What is SCADA?
 What is data acquisition?
 Where and why, use of SCADA?
Application area :
 Industrial processes : chemical, power generation and
distribution, metallurgy, …
 Nuclear processes : reactors, nuclear waste, ...
 Experimental physics : HEP laboratories
 Application size:
 20 k I/O to 450 K I/O,
 1 M I/O under development
Jul 16, 2009 SCADA 3

4. ERP Systems
SCADA ? Expert Systems
Supervisory Data
And Acquisition
Control
Archiving, Logging,
Graphics and Batch processing Access Control, Alarms
Distributed database
Data Server Data Server PLC’s
Field Bus
Control Programs
Jul 16, 2009 SCADA 4

5. Architecture
 Hardware
 Software
Jul 16, 2009 SCADA 5

6. Hardware
Typical Hardware Architecture
Jul 16, 2009 SCADA 6

7. Software Architecture
Jul 16, 2009 SCADA 7

8. Software Architecture
 Communication
Internal Communication
Access to Devices
 Interfacing
H/W
 Multiple communication protocols supported in a single system
 Support for major PLCs/DCSs but not VME
S/W
 API
 ODBC, DDE and OLE I/F to PC Products
 OPC Client and OPC Server
 ActiveX Containers
 Scalability
 Database
Configuration DB, alarm DB, Archive DB, log DB and
RTDB resides in the memory of the servers
Jul 16, 2009 SCADA 8

9. Functionality
 Generic SCADA functionality
 Access Control,
 MMI,
 Trending,
 Alarm Handling,
 Logging, Archiving,
 Report Generation,
 Automation.
Jul 16, 2009 SCADA 9

10. Functionality Contd..
 Access Control
Users - allocated to groups
group - defined read/write access
 MMI
multiple screens
library of standard graphical symbols
dragged and dropped
zooming, re-sizing, scrolling...
Links - pages to navigate
Jul 16, 2009 SCADA 10

11. Functionality Contd..
 Trending
based on parameters on specific chart
can be predefined or defined on-line
more than 8 trended parameters per chart
both real-time and historical trending
zooming and scrolling
 Alarm Handling
based on limit and status checking
handled centrally
E-mails can be generated
Jul 16, 2009 SCADA 11

12. Functionality Contd..
 Logging, Archiving
 Data stored in compressed and proprietary format
 Logging / Archiving either for a set number of parameters or for
a set period of time
 Logging / Archiving can be frequency or event driven *
 Logging of user actions together with a user ID
 VCR facility for playback of stored data
 Writing logs into RTDB
 Report Generation
 Reports created using SQL type queries to the RTDB or logs
 Automatic generation, printing and archiving of reports
 Use of ‘components’ for report generation
Jul 16, 2009 SCADA 12

13. Functionality Contd..
 Automation
triggered by events
defined in scripting languages
send e-mail ,write into RTDB
recipes
Sequencing
Jul 16, 2009 SCADA 13

14. Development Tools
 Project editor
 Graphics editor
 Configuration through parameter templates
 Scripting language
 Driver Development Tool Kit
 And more…
Jul 16, 2009 SCADA 14

15. Data Access Mechanism's
Alarm Server
 Alarm Server typically poll
data from the data server
( -> impact on network Data Server
bandwidth) Polling
More advanced techniques like
publish / subscribe are
available in some cases
Po
l
l in
g
 Data from field buses are
mainly polled
Field Bus
Jul 16, 2009 SCADA 15

16. Conclusion
SCADA is a control system with
•More frond end functionality
•More interfaces and efficient storage
•More record or device oriented configuration
•but System wide configuration tools are needed
•are less expensive than DCS, but offer different functionality
than DCS
•And finally various applications
Jul 16, 2009 SCADA 16

17. References
 www.scadanews.com
 www.princeton-indiana.com/wastewater/pages/scada/scada-overview.h
 www.ref.web.cern.ch/ref/CERN/CNL/2002/003/scada/
 www.sss-mag.com/scada.html
 www.scada.com
Jul 16, 2009 SCADA 17