ALSTOM   V0701596-001102 可编程逻辑控制器 一种具有微处理器的用于自动化控制的数字运算控制器

V0701596-001102   可编程逻辑控制器

可编程逻辑控制器(Programmable Logic Controller, PLC)，一种具有微处理器的用于自动化控制的数字运算控制器，可以将控制指令随时载入内存进行储存与执行。可编程控制器由CPU、指令及数据内存、输入/输出接口、电源、数字模拟转换等功能单元组成。早期的可编程逻辑控制器只有逻辑控制的功能，所以被命名为可编程逻辑控制器，后来随着不断地发展，这些当初功能简单的计算机模块已经有了包括逻辑控制、时序控制、模拟控制、多机通信等各类功能，名称也改为可编程控制器(Programmable Controller),但是由于它的简写PC与个人电脑(Personal Computer)的简写相冲突,加上习惯的原因，人们还是经常使用可编程逻辑控制器这一称呼， 并仍使用PLC这一缩写。
工业上使用的可编程逻辑控制器E经相当或接近于一台紧凑型电脑的主机， 其在扩展性和可靠性方面的优势使其被广泛应用于各类I业控制领域。不管是在计算机直接控制系统还是集中分散式控制系统DCS,或者现场总线控制系统FCS中,总是有各类PLC控制器的大量使用。PLC的生产厂商很多,如西门子、施耐德、三菱、台达等，几乎涉及工业自动化领域的厂商都会有其PLC产品提供。

Programmable Logic Controller (PLC) is a digital arithmetic controller with a microprocessor for automation control, which can load control instructions into memory at any time for storage and execution. The programmable controller consists of functional units such as CPU, instruction and data memory, input/output interface, power supply, and digital to analog conversion. In the early days, programmable logic controllers only had the function of logical control, so they were named programmable logic controllers. Later, with continuous development, these computer modules with simple functions had various functions, including logic control, timing control, analog control, multi machine communication, and so on. The name was also changed to Programmable Controller, However, due to the conflict between its abbreviation PC and the abbreviation of Personal Computer, and due to habitual reasons, people still often use the term programmable logic controller and still use the abbreviation PLC.
The programmable logic controller E used in industry is equivalent to or close to a compact computer host, and its advantages in scalability and reliability make it widely used in various industrial control fields. Whether in computer direct control systems, centralized decentralized control systems DCS, or fieldbus control systems FCS, there is always a widespread use of various types of PLC controllers. There are many manufacturers of PLC, such as Siemens, Schneider, Mitsubishi, Delta, etc. Almost all manufacturers involved in the industrial automation field will provide their PLC products.