What Is SCADA?: SCADA Systems Explained

If you have been around industrial automation, you surely have heard the word, but have you ever wondered what “SCADA” stands for and its origins? Knowing the meaning of SCADA is especially important in modern manufacturing, where control systems have sprawled across facilities, driving the need for more advanced networks and computing solutions. In this guide, you’ll learn that SCADA is more than just another technical acronym — it’s the backbone of modern industrial processes.

SCADA Explained

The term “SCADA” started to emerge in the 1970s as industrial process controls were becoming more advanced. Supervisory control and data acquisition (SCADA) systems consist of software and hardware elements designed to monitor and control industrial processes in real-time. 

The early SCADA systems used mainframe computers to collect data from remote sites and provide operators with the ability to monitor and control processes from a central location. Today, SCADA is often used interchangeably with terms like Industrial Control System (ICS) and Distributed Control System (DCS). Historically, SCADA was more focused across widespread geographical areas, but the concepts translate to even the most basic control systems in the modern age.

In SCADA systems, supervisory control provides high-level management and decision-making capabilities, while data acquisition involves gathering and processing data from the field. Here are the critical components of a traditional SCADA system:

• Remote terminal units (RTUs) or programmable logic controllers (PLCs): These are hardware devices installed at remote sites to monitor and control field devices and sensors.
• Sensors and field instruments: These devices measure various physical parameters such as temperature, pressure, flow rate and level. They provide input to the RTUs or PLCs.
• Communication infrastructure: This infrastructure includes wired or wireless communication networks that facilitate data transmission between RTUs or PLCs and the central SCADA server.
• SCADA server: The central processing unit collects, processes and stores data received from RTUs or PLCs. The server also facilitates human-machine interaction through the HMI.
• Human-machine interface (HMI): This user-friendly interface allows operators to monitor the system’s status, control operations and receive alarms and notifications.
• Data historian: This component stores historical data for analysis, reporting and compliance purposes. The stored data enables trend analysis and performance evaluation.
• Alarm management system: This software detects abnormal conditions or events in the system and alerts operators for timely intervention.
• Database management system (DBMS): A DBMS is a software tool that organizes, stores and retrieves data efficiently, ensuring data integrity and accessibility.
• Security features: These include measures such as firewalls, encryption, authentication and access control mechanisms to safeguard the SCADA system from unauthorized access and cyber threats.

How Does SCADA Work?

At their core, SCADA solutions control real-time data acquisition from remote locations. These systems involve several key components working in tandem. Here’s a breakdown of how a SCADA system typically works:

1. Data Acquisition

SCADA systems collect real-time data from various sensors and devices distributed throughout the industrial process or facility.

2. Data Transmission

The collected data is transmitted to a central supervisory control and data acquisition unit — the SCADA server. This is done through communication networks, which can be wired, such as Ethernet, or wireless, such as Wi-Fi or cellular networks.

3. Data Processing and Analysis

Upon receiving the data, the SCADA server processes and analyzes it. As a result, it can provide insights into the system’s operational status. This analysis can identify trends, detect anomalies and generate alarms for deviations from predefined thresholds.

4. HMI

The processed data is then presented to human operators via the human-machine interface (HMI). The HMI allows operators to visualize the system’s status, monitor performance metrics and control various aspects of the process.

5. Control Actions

Based on the information displayed on the HMI, operators can take control actions. These actions can include adjusting setpoints, initiating commands or activating or deactivating equipment. These control actions optimize the system’s performance or respond to abnormal conditions.

6. Response and Feedback

The SCADA system continuously monitors the effects of controlled actions and provides operators with real-time feedback. This feedback loop ensures operators can make informed decisions to maintain the system’s stability, efficiency and safety.

7. Data Storage and Reporting

SCADA systems often include data logging capabilities. Here, they store historical data for analysis, reporting and compliance purposes. This stored data can help identify long-term trends, conduct performance evaluations and meet regulatory requirements.

Who Uses SCADA Systems?

SCADA industrial control systems have widespread applications across various important industries. Here’s a brief list of sectors that most commonly use SCADA systems:

• Food and beverage
• Dairy
• Consumer packaged goods
• Life sciences and pharmaceuticals
• Specialty chemical
• Metal, mining and cement
• Energy and utilities
• Industrial

How Do SCADA, HMI, and PLC Work Together?

SCADA and HMI work in tandem to enable efficient industrial automation processes. SCADA systems, with their supervisory capabilities, gather real-time data from various sensors and devices across the industrial environment. HMIs then process and display this data, providing a user-friendly interface for operators to monitor and control the systems. Together, they create a cohesive ecosystem where operators can access both macro- and micro-level insights.

In this relationship, PLCs play a crucial role in handling the control logic and decision-making processes within the system. They receive commands from the SCADA/HMI software and execute them by controlling actuators, motors, valves, and other devices. SCADA, HMI, and PLCs form a symbiotic relationship where SCADA gathers and processes data, HMIs provide intuitive interfaces, and PLCs execute control commands.

The Role of RTUs in SCADA/HMI Software

RTUs act as intermediaries between field devices and the central control system. They collect data from sensors, meters, and other equipment in remote locations and transmit it to the SCADA/HMI software for analysis and monitoring. RTUs also receive commands from the central system and execute control actions in the field, such as adjusting valve positions or activating pumps. This ensures real-time data acquisition and control, enabling operators to make informed decisions and optimize industrial processes efficiently.

Applications of HMI and SCADA

SCADA and HMI systems are versatile and extend across various industries, including healthcare, food and beverage, and consumer packaged goods.

Health Care

SCADA/HMI software monitors and controls parameters like temperature, humidity, pressure, and ventilation in hospital environments, ensuring optimal patient care and safety conditions. They also oversee medical equipment performance, detect faults, and trigger alerts in case of malfunctions, facilitating data logging, trend analysis, and reporting for informed decision-making.

Discover how Malisko’s comprehensive automation solutions transformed a health care optics manufacturer’s critical processes to meet regulatory compliance within record time. 

Read the full case study now!

Food and Beverage

SCADA/HMI software ensures consistent product quality, maximizes production efficiency, and maintains stringent safety standards. SCADA systems monitor and control production processes from raw material handling to final packaging, while HMI interfaces provide visual representations of the process, helping maintain optimal conditions.

Read a case study on how Malisko transformed a leading dairy producer’s separator process, enhancing yield and consistency.

Consumer Packaged Goods

SCADA/HMI software optimizes production processes, ensures product quality, and efficiently meets consumer demand. SCADA systems monitor and control various manufacturing aspects, and HMI interfaces provide operators with intuitive visualizations to monitor performance and quickly make necessary adjustments.

Read our detailed case study to discover how Malisko helped a leading laundry product manufacturer boost productivity and efficiency.

Benefits of Implementing SCADA/HMI Systems

Implementing SCADA/HMI systems offers several advantages:

1. Enhanced operational visibility with real-time data visualization.
2. Increased efficiency through automation and better data management.
3. Improved safety with continuous monitoring and alarms.
4. Advanced data analytics for trend forecasting, diagnostics, and process optimization.
5. Remote control and monitoring capabilities for faster issue responses.
6. Scalability to meet changing operational needs.
7. Cost reduction through optimized resource usage and reduced manual interventions.

Partner With Malisko to Maximize Efficiency

Leveraging SCADA/HMI systems’ collaborative capabilities can provide numerous benefits. However, deploying and maintaining these systems requires specialized expertise. At Malisko, we specialize in providing high-quality HMI/SCADA consulting services tailored to meet your unique automation needs. Let us help your business streamline productivity and improve efficiency with our expertise in modernizing plant floor controls and implementing process automation systems.

Contact us online today to start a conversation about what we can do for you.