1. SCADA, or supervisory control and data acquisition, is a system comprised of hardware and software components used to monitor and control industrial processes.
2. With a SCADA system, manufacturers are able to collect and analyze real time production data, monitor and manage alarms, and program automatic control responses triggered by certain events or system parameters.
3. There are different types of SCADA systems that can be considered as SCADA architectures of four different generations:
- First Generation: Monolithic or Early SCADA systems
- Second Generation: Distributed SCADA systems
- Third Generation: Networked SCADA systems and
- Fourth Generation: Internet of things technology, SCADA systems
1. The core functions of SCADA include:
- System monitoring
- Automated control of industrial processes and machines
- Data collection and analysis
- Event and Alarm Notifications
- Reporting
- Control industrial processes locally or at remote locations
- Monitor, gather, and process real-time data
- Directly interact with devices such as sensors, valves, pumps, motors, and more through human-machine interface (HMI) software
- Record events into a log file
SCADA ARCHITECTURE
1. The SCADA system includes the following components: local processors, operating equipment, PLCs, instruments, remote terminal unit, intelligent electronic device, master terminal unit or host computers and a PC with human machine interface.
2. Above figure depicts an integrated SCADA architecture which supports TCP/IP, UDP and other IP based communication protocols as well as industrial protocols like Modbus TCP, Modbus over TCP or Modbus over UDP. These all work over cellular, private radio or satellite networks.
3. To perform these functions, SCADA integrates with sensors and other measuring devices, which can be in either digital or analog form, to collect data.
4. The collected data is then sent to remote terminal unit (RTU) or programmable logic controller (PLC) to be translated to usable information.
5. Finally, the information is relayed to a human machine interface (HMI) or other types of displays for operators to analyze and interact with.
MONOLITHIC/ EARLY SCADA SYSTEMS
1. Minicomputers are used earlier for computing the SCADA systems. In earlier times, during the time of first generation, monolithic SCADA systems were developed wherein the common network services were not available.
2. Hence, these are independent systems without having any connectivity to other systems.
3. All the remote terminal unit sites would connect to a back-up mainframe system for achieving the first generation SCADA system redundancy, which was used in case of failure of the primary mainframe system.
4. The functions of the monolithic SCADA systems in the early first generation were limited to monitoring sensors in the system and flagging any operations in case of surpassing programmed alarm levels.
DISTRIBUTED SCADA SYSTEMS
1. In the second generation, the sharing of control functions is distributed across the multiple systems connected to each other using Local Area Network (LAN).
2. Hence, these were termed as distributed SCADA systems. These individual stations were used to share real-time information and command processing for performing control tasks to trip the alarm levels of possible problems.
3. 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.
4. But even in the second generation systems also the network protocols were not standardized.
5. The security of the SCADA installation was determined by a very few people beyond the developers, as the protocols were proprietary. But generally the security of the SCADA installation was ignored.
NETWORKED SCADA SYSTEMS
1. The current SCADA systems are generally networked and communicate using Wide Area Network (WAN) Systems over data lines or phone.
2. These systems use Ethernet or Fiber Optic Connections for transmitting data between the nodes frequently.
3. These third generation SCADA systems use Programmable Logic Controllers (PLC) for monitoring and adjusting the routine flagging operators only in case of major decisions requirement.
4. The first and second generation SCADA systems are limited to single site networks or single building called as sealed systems.
5. 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.
6. There will be several parallel working distributed SCADA systems under a single supervisor in network architecture.
INTERNET OF THINGS
1. In fourth generation, the infrastructure cost of the SCADA systems is reduced by adopting the internet of things technology with the commercially available cloud computing.
2. The maintenance and integration is also very easy for the fourth generation compared to the earlier SCADA systems.
3. These SCADA systems are able to report state in real time by using the horizontal scale from the cloud computing facility; thus, more complex control algorithms can be implemented which are practically sufficient to implement on traditional PLCs.
4. The security risks in case of decentralized SCADA implementations such as a heterogonous mix of proprietary network protocols can be surpassed using the open network protocols such as TLS inherent in the internet of things which will provide comprehendible and manageable security boundary.
TYPE OF USERS
1. Typical SCADA projects for clients across a wide range of industries:
-Food and beverage processing
-Pharmaceutical/Bio-tech
-Water/Wastewater management
-HVAC and commercial building management
-Energy pipelines and utilities
-Seafood processing
-Sorting and fulfillment
-Energy management and refrigeration
TYPES OF PLATFORMS & APPLICATIONS
1. The most popular platforms include Rockwell Factory Talk, Siemens WinCC, Wonderware Systems Platform, and Ignition.
2. Each of these platforms can be programmed with modern web languages such as HTML5, Python, and PHP, and integrated with generalized database software such as SQL.
3. Energy-use monitoring and metrics is a common application for a SCADA system.
4. In this application, the SCADA system can help operators analyze energy use data taken from connected equipment and use that data to cut costs and energy waste.
BENEFITS
1. SCADA systems also enable the ability to automate the control of industrial processes and machines that would otherwise be too complex for manual human control.
2. Through the use of sensors and measuring devices, SCADA systems can detect abnormal parameters or alarms and automatically respond with a programmed control function.
3. For example if an alarm occurred signaling to much pressure in a line, the SCADA system would trigger a programmed response to open a pressure relief valve to return pressure levels to a normal amount.
4. SCADA is also often used for water/wastewater treatment plants to manage the various stages of water treatment, as well as in food and beverage facilities to optimize production rates and increase product quality.
5. The information derived from a SCADA system can facilitate data-driven decisions and lead to increased output, reduced costs, and greater control of your processes.
6. Another benefit of SCADA is instant notification and automated response to system alarms.
7. With the immediate knowledge of issues in the production process, operators and back-up systems are able to respond quicker to reduce equipment downtime and wasted product.
8. SCADA systems are crucial for industrial organizations since they help to maintain efficiency, process data for smarter decisions, and communicate system issues to help mitigate downtime.
Source: https://www.processsolutions.com/understanding-scada-and-what-it-can-do-for-you/
https://www.watelectronics.com/scada-system-architecture-types-applications/
