SCADA (Supervisory Control and Data Acquisition)

What is SCADA?

SCADA (Supervisory Control and Data Acquisition) is an industrial system that is used to monitor, control, and analyze an industrial environment or process. SCADA is used across multiple industries, including manufacturing plants, food production, transit systems, water/wastewater systems, recycling plants, electric generation, petrochemical systems, and more. Any industrial process that requires precise monitoring, analysis, and control is likely to utilize SCADA in some way or another.

Through remote controllers such as PLCs (Programmable Logic Controllers) and RTUs (Remote Terminal Units), the SCADA system gathers real-time data and communicates with industrial equipment, such as valves, pumps, sensors, and user interfaces.

One of the main advantages of a SCADA system is that it enables manufacturers to manage operations from remote locations, meaning operators do not need to be right by the machine to enact control and real adjustments.

What Does a SCADA System Do?

While it might be hard to pin down all the functions of a SCADA system, we can break the system down into 5 broad functions.

• Data Acquisition: SCADA systems collect data from sensors in the field to provide keen insights into the status of the industrial process or machine.

• Remote Control: Using this collected data, SCADA systems employ field actuators to control and affect the functions of the process or machine.

• Real-time & Historical Data: SCADA systems enable organizations to review real-time data while also tracking historical performance, enabling them to respond to immediate needs while analyzing past performance.

• Data & Control Presentation: The data collected from the various levels of the SCADA system are compiled and visually displayed. Operators can then make changes directly within the interface.

• Bi-Directional Data Flow: Data flows up and down the SCADA architecture, gathering data and communicating control measures. Field components, such as sensors, relay data to the centralized computer while the centralized computer relays control directives to the field components, such as actuators.

How Does a SCADA System Work?

For a SCADA system to perform its function, there are several components that need to work together. Remember, the 3 main functions of a SCADA system are to gather information, analyze data, and enact control measures. Each of these components facilitates these roles.

• Sensors: These devices work like a gauge or meeter, detecting inputs from the industrial processes, and providing the SCADA system with valuable real-time information.

• RTUs (Remote Telemetry Units): These are field controllers that interact with sensors to collect valuable information.

• Actuators: While sensors detect and convey the status of the process, actuators are devices that enable people and systems to control the machine or industrial process. These include but are not limited to, switches, control valves, electric motors, dials, etc.

• PLCs (Programmable logic controllers): These are field controllers that interact with actuators out in the field to adjust machine or process operations.

• SCADA Supervisory Computers: These computers gather data from RTUs and communicate with PLCs in the infrastructure.

• HMI (Human Machine Interface): This software is the window to the whole SCADA setup. It takes the information gathered and presents it to the user within an easy-to-view interface. It also enables people to modify and control various factors within the process.

SCADA Architecture: How It All Fits Together

For all the components of a SCADA system to work properly, there needs to be a very specific architecture, consisting of levels 0-4.

• Level 0 - Field Level: Here is where the field devices such as sensors and actuators sit. They relay data and enact control actions.
• Level 1 - Direct Control: This level is for PLCs and RTUs that interact with sensors and actuators in level 0.
• Level 2 - Plan Supervisory: This level contains all supervisory computers that interact with RTUs and PLCs.
• Level 3 - Production Control: With multiple supervisory computers in Level 2, this level aggregates all data from Level 2 to produce ongoing reports and enact various control functions.
• Level 4 - Production Scheduling: This level pertains to systems and interfaces that operators use to manage production processes and machines.

Top 5 Benefits of SCADA Systems in Manufacturing

• Real-Time Data Collection: With strategically placed sensors throughout key manufacturing processes, SCADA provides organizations with actionable insight. This level of data acquisition allows companies to improve product quality, increase productivity, reduce downtime, and more.

• Remote Monitoring and Control: With real-time data acquisition, operators can receive information and enact meaningful changes from remote locations. This remote capability is much better than past environments where an operator would have to be beside the machine to see or do anything.

• Reduce Costs: SCADA systems help manufacturers cut costs by reducing energy consumption and highlighting inefficiencies. By empowering organizations to monitor and control remote locations, companies can quickly anticipate waste, find inefficiencies, and alleviate problems.

• Scalability & Customization: No two SCADA implementations are exactly alike. This is because no two companies are the same. Despite the relative complexity of various components, SCADA systems and hardware can be a powerful asset to any manufacturing organization.

How to Boost SCADA Effectiveness Even Further

One key disadvantage of SCADA solutions is that they can be complicated to set up and use. And while not all personnel know the ins and outs of SCADA procedures, there is a tool that can walk them through the correct processes at any moment.

Work instruction software guides workers with visual and intuitive step-by-step guides. Organizations can create best practices that address key repeatable procedures or they can create dynamic processes that instruct the worker based on the current needs of the situation.

By providing clear SCADA instructions and procedures, the workforce is better situated to assist and improve the overall efficiency of the SCADA system.