Programmable controller referred to

Programmable controller referred to as PLC, is a combination of microcomputer technology and relay conventional control technology, is a new controller developed on the basis of sequence controller and microcomputer controller, is a microprocessor as the core of the digital control of the special computer. Since 1969, according to the characteristic of industrial automatic control and needs to be developed and the first since the introduction of PLC, so far has more than 30 years, although its development includes the prophase of the inheritance and evolution of control technology, but it is different from the sequence controller and general microcomputer control device which not only make full use of the advantages of the microprocessor to meet the requirements of real-time control in the field of all kinds of industrial, but also take care of the electrical operation and maintenance personnel skills and habits, to abandon the microcomputer commonly used computer programming language expression, forming a unique style and then to relay ladder graph based image programming language and modular software structure, The compilation of user program is clear and intuitive, convenient and easy to learn, debugging and error checking are very easy. After the user buys need PLC, need to press manual or prompt only, do a few installation wiring and user program compilation work, can be flexible and convenient PLC application in production practice. Moreover, the compilation, modification and debugging of user programs do not require special knowledge of computer programming languages. In this way, the mystery of "computer" was removed and the universal application of computer technology was promoted. PLC is the most important advanced control technology in modern industrial automation control. PLC has become the three pillars of modern industrial control, PLC, CAD/CAM, ROBOT), one of its reliability, strong logic function, xiaoke online volume change control procedures, with functions of remote communication network, can easily interface with the computer, the analog control, high about numeration excellent properties such as high performance, such as a control module. The PLC is a combination of intersection with the countdown