Industrial Control Systems

Industrial control

It is a general term for a computer system that uses a bus structure to detect and control the production process and its electro mechanical equipment and process equipment. Referred to as the industrial computer. It consists of two parts: computer and process input and output (I/O). 

The computer is composed of a host, an input/output device, an external disk drive, a tape drive, and the like. A part of the process input/output channel is added outside the computer, and the test data for completing the industrial production process is sent to the computer for processing; on the other hand, the computer is required to exercise the control command for the production process control and convert the information into the control variable of the industrial control object. 

The signal is sent to the controller of the industrial control object. The controller controls the operation of the production equipment. The main categories of industrial computer are: IPC (PC bus industrial computer), PLC (programmable control system), DCS (distributed control system), FCS (field bus system) and CNC (CNC system).

1, IPC

That is, an industrial computer based on a PC bus. According to IDC statistics in 2000, PCs accounted for more than 95% of general-purpose computers. Because of their low price, high quality, large output, and abundant software/hardware resources, they have been familiar and recognized by the vast number of technicians. 

Annoying foundation. Its main components are industrial chassis, passive backplane and various boards that can be inserted into it, such as CPU cards, I/O cards, etc. It also adopts all-steel casing, machine bar bead filter, double positive pressure fan and other EMC (Electro Magnetic Compatibility) technology to solve electromagnetic interference, vibration, dust, high/low temperature and other problems in the industrial field.

IPC has the following characteristics:

Reliability: Industrial PCs have dust and smoke, high/low temperature, humidity, vibration, corrosion and rapid diagnosis and maintainability. The MTTR (Mean Time to Repair) is generally more than 100,000 hours.

Real-time, industrial PC real-time online detection and control of industrial production process, quick response to changes in working conditions, timely acquisition and output adjustment (watchdog function is not available in ordinary PC), self-reset in distress, Ensure the normal operation of the system.

Expandability, industrial PC has a strong input and output function due to the base plate + CPU card structure, which can expand up to 20 boards, and can be used with various peripherals, boards such as controllers and video surveillance in the industrial field. Systems, vehicle detectors, etc. are connected to accomplish various tasks.

Compatibility, can use ISA and PCI and PICMG resources at the same time, and support various operating systems, multi-language assembly, and multi-tasking operating system.

2, programmable controller (PLC)

PLC full name ProgrammableLogicController, Chinese full name is programmable logic controller, defined as: an electronic system for digital operation, designed for industrial environment applications. It uses a class of programmable memory for its internal memory program, performing user-oriented instructions such as logic operations, sequence control, timing, counting and arithmetic operations, and controlling various types of machinery through digital or analog input/output. Or the production process. 

Programmable Logic Controller (ProgrammableLogicController) is a digital computing operation electronic system designed for industrial applications. It uses a programmable memory that stores instructions for performing operations such as logic operations, sequence control, timing, counting, and arithmetic operations, and controls various types of mechanical equipment or production through digital or analog input and output Process.

Programmable controller is a new type of universal automatic control device developed in combination with computer technology and automatic control technology. It is a replacement product of traditional relays.

With the rapid development of microelectronics technology and computer technology, programmable controllers have more functions of computers, not only for logic control, but also for data processing, communication, and network functions. 
Because it can change the control process through software, and has the characteristics of small size, convenient assembly and maintenance, simple programming, high reliability, strong anti-interference ability, etc., it has been widely used in various fields of industrial control, greatly promoting mechatronics. process.

3. Decentralized control system (DCS)

It is a high-performance, high-quality, low-cost, flexible configuration of distributed control system products, which can form a variety of independent control systems, distributed control system DCS, monitoring and data acquisition system (SCADA), to meet various industrial fields. The need for process control and information management. 

The system's modular design, reasonable software and hardware function configuration and easy to expand capabilities, can be widely used in the decentralized control of various large, medium and small power plants, the transformation of power plant automation systems and steel, petrochemical, paper, cement, etc. Industrial production process control.

4. Fieldbus system (FCS)

It is an all-digital serial, two-way communication system. In-system measurement and control devices such as probes, actuators and controllers can be connected, monitored and controlled. In the classification of the factory network, it is used as a local network for process control (such as PLC, LC, etc.) and application of intelligent instruments (such as inverters, valves, bar code readers, etc.), and has embedded control applications distributed on the network. Features. Due to its broad application prospects, many foreign powerful manufacturers are competing to invest in product development. There are more than forty types of fieldbuses known internationally. The typical fieldbuses are: FF, Profibus, LONworks, CAN, HART, CC-LINK, etc.

5, CNC system (CNC)

The modern numerical control system is a numerical control system using a microprocessor or a special microcomputer. The system logic (software) stored in the memory is used to realize the control logic, realize some or all of the numerical control functions, and connect with peripheral devices through the interface, which is called a computer. CNC, referred to as CNC System.

CNC machine tools are mechatronic products formed by the penetration of new technologies represented by numerical control systems into the traditional machinery manufacturing industry; their technical scope covers many fields: (1) mechanical manufacturing technology; (2) information processing, processing and transmission technology; (3) automatic control technology; (4) servo drive technology; (5) sensor technology; (6) software technology.