The industrial automatic control system summarizes, analyzes, and organizes various information collected by sensors and local area networks through industrial control computers, achieving the integration of information management and automatic control, and ensuring information security through permission authentication.
Industrial automation control is mainly divided into three parts: industrial automation systems, hardware, and software. The widely used industrial automation control equipment and systems nowadays mainly include servo systems, stepper systems, frequency converters, sensors, instruments and meters, human-machine interfaces, data acquisition and monitoring control systems, decentralized control systems, programmable logic controllers, fieldbus control systems (FCS), etc.
After years of development, the structure and core components of modern industrial automation control have also begun to take shape:
1. Programmable Logic Controller (PLC). Programmable Logic Controller (PLC) is a digital operation electronic system designed specifically for use in industrial environments. It adopts a programmable memory that stores instructions for performing logical operations, sequential control, timing, counting, and arithmetic operations inside, and controls various types of mechanical equipment or production processes through digital or analog input and output.
2. Data acquisition and monitoring control system redundancy technology (high reliability of the system).
System SCADA. A Data Acquisition and Monitoring System (SCADA) is a software application that primarily collects system status information, processes data, and communicates over long distances to achieve control over equipment and conditions.
3. Remote terminal unit RTU. Remote terminal unit (RTU) is a modular and special computer measurement and control unit designed for long communication distances and harsh industrial environments. RTU products are widely used in SCADA systems.
4. Communication technology. The communication types of industrial control systems are divided into three types based on the hierarchical structure of the system, namely standard communication bus (external bus), fieldbus (Fieldbus), and local area network communication. The industrial control system connects the host with various devices through these three types of communication methods, transmits on-site signals to the control level, and then transmits control level information to the monitoring level and management level.
5. Protocol. The communication between the on-site network and the control network of the industrial control system, the communication between various industrial control devices in the on-site network, and the communication between various components of the control network often use the unique communication protocol of the industrial control system. At present, industrial control systems involve protocols such as fieldbus (CAN, DeviceNet, Profibus DP, Profibus PA, etc.), industrial Ethernet (EtherNet/IP, EtherCAT, HSE, Profinet, EPA, Modbus, etc.), and industrial wireless network (IEEE 802.11, ZigBee, Rfieldbus, etc.).
