SCADA systems are critical components of many industries and play a pivotal role in safe and efficient operation.
But what is a SCADA system, exactly? And what are the key components and design considerations when creating one?
This blog post will provide an overview of SCADA systems, their components, architecture, and history.
What is SCADA system?
It is a control system that collects data from industrial processes, typically over a wide area, often for monitoring and control.
It can include hardware and software for gathering data, transmitting the data across a network, and displaying the data on operator screens.
This system connects sensors and remote servers to control equipment such as pumps and motors. The acronym SCADA stands for Supervisory Control And Data Acquisition.
How does it work?
A typical SCADA system includes a central computer that collects data from numerous field devices, such as sensors and controllers. Then the data is processed and displayed on a human-machine interface (HMI), which allows operators to monitor the process and make changes as necessary.
Using logic-based rules, operators can select the completion of specific tasks or the beginning of others to maintain the desired output at the remote site. That can be everything from regulating a power plant to overseeing a water filtration system.
In some cases, the HMI may also be used to issue alarms or take automated action in response to certain conditions.
While SCADA systems have been in use for many years, technological advances have made them increasingly sophisticated and capable of integrating with other systems, such as enterprise resource planning (ERP). As a result, the system plays an increasingly important role in the operation of industrial facilities worldwide.
SCADA system components
The key components include:
The field devices
Field devices are input devices such as sensors, valves, and actuators that collect data from the process being monitored or controlled. Both devices are controlled and monitored by field controllers.
Field controllers
The control room operator interface equipment allows the operator to view process data and issue commands to the field devices. Controllers use algorithms to process data from field devices and make decisions on how to control operations in the field.
Two types of controllers are there.
- Remote terminal units (RTUs) – These individual devices scattered around the plant or facility collect data from sensors and then relay that information back to the master station.
- Programmable logic controllers (PLCs) – These devices interface with the actuators (controllers) to control processes.
Supervisory computer
The main computer oversees and controls the entire SCADA process, which collects data from field devices and provides commands to field controllers.
Human-machine interface (HMI)
This graphical interface allows the operator to view real-time data from the RTUs and make changes to controller settings, if necessary.
Communication infrastructure
This enables the communication between the field devices and field controllers. It can be either wired or wireless.
SCADA system architecture
- The first layer (Field devices) consists of sensors and actuators that collect data and perform actions in the field.
- The second layer (Field controllers) includes local controllers such as RTUs and PLCs. They get data from sensors and send the command to actuators.
- The third layer (Local supervisory) consists of local supervisory devices that gather data from field controllers and give commands to those who must carry them out.
- The fourth layer ( Production control) includes many local supervisory systems that collect data from local supervisory systems and generate reporting to the next layer.
- The fifth layer (Main monitoring station) includes a SCADA computer system and manages all ongoing processes.
History of SCADA
Monolithic SCADA systems
We can call them 1st generation systems. In the 1960s and 1970s, RTUs at industrial sites were directly connected to mainframe computers.
Distributed systems
This is the second-generation system. In the 1980s, because of powerful computers, the system could share data at the plant level.
Networked systems
It can be a third-generation system. In the 1990s, the system became more interoperable because of the development and adoption of standard network protocols.
It meant they could be scaled across enterprises’ industrial infrastructures without difficulty or risk because enterprise integration was possible through a wider variety of devices used in conjunction with these networks – something which would have been impossible before.
IIoT-based systems
This is the latest or fourth-generation system. In the 2000s, the system is introduced as the SCADA system, and since then, vendors have been developing web-based software to enable data transparency across platforms.
Today’s cloud computing has made this even more important as it changes how SCADAs function with their emphasis on accessibility through universally available interfaces such as browsers running on handheld devices or laptops at home; desktop computers sitting behind your desk.
SCADA architecture is used in various industries, from manufacturing to transportation to energy production. Its popularity is due to its ability to provide real-time monitoring and control of large-scale systems and its relative affordability compared to alternative solutions.
Benefits
Enhanced communication
Current communication protocols improve accessibility to information and control.
Scalability
Modern systems are more scalable than legacy systems. That means they can handle more workloads and meet the demands of modern businesses.
Additionally, they are better supported by hardware and software, making them more reliable and easier to use. Finally, SCADA systems can use cloud computing to meet demand when necessary.
Efficiency
By allowing for centralized control of distributed systems, they increase efficiency by reducing the need for manual input and oversight.
Interoperability
Interoperability between different SCADA systems allows for greater coordination and collaboration between facilities, improving overall system performance.
Finally, they are often deployed with security features that help protect critical infrastructure from cyberattacks.
Great support
The system provides a wide range of support options. Legacy systems may have limited options, while modern systems are more likely to be well-supported by vendors.
That makes it easier to determine help when you need it. Commercial off-the-shelf hardware, open networking standards, and modern software development platforms make third-party support more accessible.
FAQs
Who uses SCADA?
It is used by many organizations and businesses, including water and wastewater utilities, power companies, gas utilities, oil refineries, chemical plants, food processing plants, mining, manufacturing, and power generation.
The system is often used to monitor critical infrastructures, such as dams, bridges, and nuclear power plants.
Typically it can be used in environments that are dangerous or remote.
Conclusion
SCADA systems provide an efficient and effective way to manage and monitor industrial processes.
They are used in various industries, including water treatment, power generation, and manufacturing. The article looked at its architecture, components, and history.
