Industrial control systems consist of three main components: sensors and actuators, controllers, and operator interfaces. The following is a detailed description of each component:
1. Sensors and actuators: Sensors and actuators are important input and output devices in industrial control systems. Sensors are used to detect physical quantities of controlled objects, such as temperature, pressure, flow, position, speed, etc., and convert this information into electrical or digital signals for input to the controller. Actuators are used to control the controller output control signals into mechanical or electrical operation signals, such as switches, valve control, motor control, etc., to control the conversion of the controlled object.
2. controller: controller is the core component of the industrial control system, including logic controller (PLC), numerical controller (CNC), process controller (DCS), etc.. The controller is responsible for receiving and processing sensor input data and user commands, and then according to the preset procedures for arithmetic and logic judgment, output control signals to control the actuator to perform the corresponding operations.
3. Operator Interface: The operator interface is the third important part of the industrial control system, including human-machine interface (HMI), operator panel, monitoring system, etc. The operator interacts with the controller through these devices. The operator interacts with the controller through these devices, sends control commands to it, checks the system operation status, diagnoses faults and carries out maintenance and repair work.
In summary, sensors and actuators, controllers, and operator interfaces are the three components of an industrial control system. Together they form a closed-loop control system that realizes automated control and monitoring of the controlled object.
Industrial Control System Security Levels
Industrial control system information security is divided into four levels 1-4, which is basically the same as the domestic information security level protection level (information system security protection level is divided into 5 levels, the actual use of 1-4), and the international standard IEC-62443 industrial control system information security level to maintain consistency (divided into 1-4).
Level 1 industrial control system: It can cause damage to industrial production and operation in general areas, or damage to the legitimate rights and interests of citizens, enterprises and other organizations and important property, but it will not harm national security (especially national economic security), environmental security, social order, public interests and human life.
Industrial control system of the second level: it will cause significant damage to the operation of industrial production in the general field, or cause damage to the operation of industrial production in the key fields, or cause serious damage to the lawful rights and interests of citizens, enterprises and other organizations and important property, or cause damage to environmental security, social order, public interests and human life, but will not damage national security (especially national economic security thereof).
Level III industrial control system: it will cause significant damage to industrial production and operation in key areas, or cause damage to industrial production and operation in critical areas, or cause serious damage to environmental security, social order, public interests and human life, or cause damage to national security (especially national economic security thereof).
Level 4 industrial control systems: can cause significant damage to the operation of industrial production in critical areas, or cause particularly serious damage to environmental security, social order, public interests and human life, or can cause serious damage to national security (in particular, national economic security thereof).