Supervisory Control and Data Acquisition (SCADA)

Supervisory control and data acquisition (SCADA) is a system of software and hardware elements that allows industrial organizations to:

• 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 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.

How does a SCADA system work?

A SCADA system consists of three main system components. Combined, they ensure that data is transmitted from the equipment that needs to be monitored and controlled (sensors, motors, etc.) to an interface where the data can be analyzed and used for reporting.

The connecting link in the SCADA architecture are the Programable Logic Controllers (PLCs) or Remote Terminal Units (RTUs). These are microcomputers that interact with both the equipment (also called field devices) on the one hand, and HMIs, which are Human Machine Interfaces, on the other hand. HMIs are also referred to as graphical user interfaces.

As the illustration shows, the PLCs and RTUs works as local collection points that send and translates data to the remote or on-site HMI and send back control commands to the field devices.

The human operators access the data through the HMI, which can either be cloud-based or based on own servers. The software interprets and displays the data in an easy-to-understand matter, so operators quickly and simply can analyze and react to alarms.

Some SCADA systems also include options for automatic control actions and an automatic reporting engine for easy-made reports.

Why is a SCADA system important?

There are many benefits of a SCADA system. Overall, SCADA systems help optimize production and control the production according to regulations within the industry. In many cases, SCADA systems are also used for troubleshooting purposes, as maintenance has become a big part of securing a continuous production flow without too many errors.

To fully understand the importance of a SCADA system, we need to go back to when industrial plants were monitored manually and relied on personnel to be on site during production. The personnel had to oversee and control operations and react to emerging issues. This was not only costly but could be dangerous for the personnel.

However, as industrial sites scaled up and became more remote, the need for more automatic solutions came about.

Fast forward to today, the initial need for more automation is still driving the SCADA development. With more automatic and semi-automatic processes, businesses can allocate their resources differently and save money in the long run.