Understanding SCADA: What Every Industrial Technician Needs to Know
Have you ever wondered how industrial processes are monitored and controlled from a centralized location? SCADA systems play a vital role in making this possible. By understanding SCADA, you can gain valuable insights into how to optimize operations, improve efficiency, and troubleshoot issues more effectively. Below, we’ll cover what SCADA systems are, as well as their components, benefits, and real-world applications.
What Are SCADA Systems?
SCADA stands for Supervisory Control and Data Acquisition. SCADA systems are a collection of software and hardware elements that directly interface with plant-floor machinery to support industrial automation.
SCADA systems allow organizations to control industrial processes and allow monitoring with real-time data.
Components of SCADA Systems
The exact composition of any given SCADA system will depend on the particular needs and process control challenges being addressed. Generally speaking, however, there are a few common categories of components.
Sensors
Sensors are a key hardware component for SCADA systems because they measure physical parameters like temperature, pressure, levels, flow, humidity, light, vibration, and much more, turning them into signals that can be processed by a computer system.
Examples of common SCADA sensor types include Resistance Temperature Detectors (RTUs), thermocouple temperature sensors, optical sensors, load cells, and level transmitters.
Actuators
While sensors allow a SCADA system to “see” what’s going on inside a plant, actuators allow it to control what’s happening. Actuators receive control signals and respond by performing actions like starting motors or opening valves.
Master Terminal Units (MTUs)
If sensors are a SCADA system’s eyes and actuators are its hands, the MTU is its brain. It’s the central computer that runs the whole show through processes like:
- Aggregating telemetry from field devices
- Processing and archiving data with timestamps
- Running data analytics
- Hosting the human-machine interface (HMI) software
- Facilitating the distribution of data across the network
- Issuing supervisory commands to controller units
While an MTU ultimately coordinates and controls the SCADA system, it typically does so with the help of semi-autonomous go-betweens called PLCs or MTUs.
Programmable Logic Controllers (PLCs)
PLCs are microprocessor-based controllers that act as intermediaries for the Master Terminal Units (MTUs). PLCs typically control a process or sequence of processes by handling a variety of tasks, like regulating the flow of materials, starting and stopping the process, and detecting problems.
Remote Terminal Units (RTUs)
RTUs are a subset of PLCs designed for industrial control and automation in remote locations. They’re compact, often rugged and/or standalone, and can be controlled remotely. This makes them useful for controlling processes in harsh conditions or those spread over a large area, while other types of PLCs are used in more controlled industrial settings.
Data Communications Infrastructure
The final hardware component common to all SCADA systems is the data communications infrastructure that connects all other components to one another and to any corporate networks.
Human-Machine Interface (HMI) Software
Human-Machine Interface software is what allows industrial technicians to “see into” the SCADA system and intervene when necessary.
HMI software typically includes features like:
- Visualization of SCADA systems data
- Remote monitoring and control of field equipment
- Built-in alarms for abnormal conditions or security breaches
Historian Software
Since SCADA systems collect an enormous amount of timestamped data, they require an industrial database known as the historian to preserve and retrieve that data. Historians are more robust than conventional databases.
Other SCADA Software
While the HMI and historian software are prominent and notable types of SCADA software, they’re far from the only software involved. Software is required to power each hardware device, edit control logic programming, and execute each aspect of process supervision, automation, asset tracking, and data management.
Real-World Applications of SCADA Systems
Supervisory Control and Data Acquisition systems are invaluable for processes where human control is problematic, including 24/7 operations and those with many control factors to consider at once.
Examples of industries that rely on SCADA for process control include:
- Power Generation, Transmission, and Distribution
- Water, Wastewater, and Sewage
- Manufacturing
- Oil and Gas
- Renewable Energy
- Mass Transit
Benefits of SCADA Systems
SCADA systems are a serious investment, but they can pay dividends in many ways.
Rapid Response
Automated process control facilitates both a fast warning of and rapid response to any problems. Constant sensor data combined with a database of previous activity can detect problems before they cause a complete breakdown. Some issues can be dealt with automatically by the SCADA system. Other cases will require human intervention, but automated alarms and remote control of the facility can still result in a faster response than manual intervention.
Improved Efficiency
The rapid detection and response to any problems improves the efficiency of a SCADA-controlled industrial system. Problems can often be dealt with before there’s downtime, avoiding the productivity loss of a shutdown.
Additionally, industrial automation makes more efficient use of staff. In some cases, full-time personnel may not even be necessary on-site in SCADA-connected facilities.
More Effective Data Analysis
The robust data collection, visualization, and analysis facilitated by a SCADA system can support more informed decision-making and result in the detection of trends or anomalies that would have otherwise gone unnoticed.
Many SCADA systems also support the ability to model different scenarios to anticipate the results of any process adjustments, enabling organizations to optimize operations while minimizing the risks.
Easier Compliance
The automated data collection of SCADA systems can make compliance with an industry’s regulatory reporting requirements simple and reliable.
Online SCADA Training for Industrial Technicians
For a successful career as an industrial technician, it’s important to stay educated on important technological innovations.
The good news is that it doesn’t mean going back to school. With Instrumentation and Control courses like ours, you can gain an in-depth understanding of the principles of SCADA systems online and on your own schedule.
Our self-paced 18-hour course is composed of 30-minute modules that are the perfect length for exploring important topics without getting bogged down with book learning. You’ll be able to work through the series in manageable chunks wherever and whenever you’ve got time.
Enroll today to enhance your industrial skills!
