Industrial automation is a complex, dynamic, and fascinating field of technology.
Introduction
In today's world, industrial automation is virtually ubiquitous. Automated systems enable manufacturing, engineering, construction, power generation, and other processes at the core of the economy to improve efficiency and productivity. Today, industrial automation is undergoing a new wave of significant development, driven by innovative technologies such as artificial intelligence (AI), cloud computing, big data, and the Internet of Things (IoT).
What is industrial automation?
Industrial automation refers to the use of automated controls, such as programmable logic controllers (PLCs) and remote terminal units (RTUs). These help control industrial processes and machinery, replacing manual intervention and dangerous automated assembly operations.
Industrial automation consists of a series of synchronized components. It performs functions such as control, sensing, supervision, and monitoring of industrial processes.
Functionally, industrial automation includes field-level (sensors and actuators), control-level, supervision, production control-level (SCADA), and information and enterprise-level (MES and ERP).
Automated control components
PLC - Programmable Logic Controller
A PLC is an industrial-grade digital computer designed to perform control functions, particularly in industrial applications.
A programmable logic controller is an electronic device used to control processes. It consists of a central processing unit; input and output devices, power supply, communication, and redundancy units. A PLC is pre-programmed according to its application and put into operation. A PLC receives inputs from the field, processes the inputs according to the completed programming, and outputs commands to field devices. It can also receive commands from plant operators via SCADA and issue commands to field devices. The functions of a PLC vary by manufacturer, but the basic architecture remains the same.
RTU - Remote Terminal Unit
RTU stands for Remote Terminal Unit. An RTU is a control device typically installed at a remote location as part of a larger system. The primary purpose of an RTU is to monitor and control field devices such as valves, actuators, sensors, etc. RTUs are an essential component of Supervisory Control and Data Acquisition (SCADA) systems, serving as an interface between SCADA control and physical processes.
An RTU consists of a hardware panel that houses one or more input/output (I/O) modules. The most important components of an RTU are the central processing unit (CPU), power supply, communication ports, and physical I/O.
DCS - Distributed Control System
A DCS (Distributed Control System) is designed to manage more complex and geographically extensive industrial processes. The entire industrial process is divided into distinct control zones, each controlled by dedicated autonomous controllers. Field devices communicate with controllers in specific control zones. These controllers are interconnected via a high-speed communication network and connected to an engineering PC, where overall control, monitoring, data logging, and alarm functions are performed. In a distributed control system, control decisions are made by plant operators rather than the controllers themselves. A DCS is a pre-designed solution that requires configuration rather than programming (like a PLC).
PAC - Programmable Logic Controller
A PAC can be considered a combination of a PLC, RTU, DCS, and PC. It possesses the discrete control capabilities of a PLC, the multitasking and storage capabilities of a PC, the multi-protocol communication and remote operation capabilities of an RTU, and the massive I/O processing capabilities of a DCS.
SCADA - Supervisory Control and Data Acquisition System
A Supervisory Control and Data Acquisition System (SCADA) is a software interface that enables plant operators to easily control and monitor various devices in industrial/plant environments. Additionally, it performs data acquisition. Operators can monitor parameters via PLC/SCADA and issue commands to field devices. SCADA cannot communicate directly with field devices; it can only do so through PLCs. All data from the field enters the I/O modules in the PLC and is stored in specific memory locations or registers. In turn, SCADA reads or writes to these memory locations. The entire control logic is stored in the PLC, not in SCADA.