PLC逻辑控制程序设计的方法与技巧

逻辑控制是指输入信号以及输出信号均为离散量信号的控制，是可编程序控制器通用的基本功能，任何一种PLC都能很方便地实现逻辑控制；实际生产控制过程中经常遇到的逻辑程序设计问题是要对输入设备的类型有充分认识，必须弄清它是动断常闭触点、还是动合常开触点，在程序中是如何区别和表示的，为突出实用性分别介绍几种逻辑控制程序设计的方法与技巧。

Methods and Techniques about How to Design The PLC Logical Control Program

The logical control means that the input and output signals are all control of the signals of discrete quantity, and it is the universal and basic function of the programmable controller, any kind of PLC can achieve expediently logical control. Problems about this we usually meet in produced processes show that we should have enough cognition to the type of the input equipment, and also must make sure that whether it's the point which move to break to often shut, or the point which move to match to often open, and make it clear that how to distinguish and express. In order to extrude its practicability, some kinds of methods and techniques about logiccal control program are mentioned in the paper.