Programming languages are the most complex,diverse,and seemingly the same,but not universal.The most commonly used programming languages can be divided into the following 5 categories:
(1)Ladder Diagram
This is the programming language most used by PLC manufacturers.It was originally evolved from the relay control diagram.It is relatively simple and most useful for discrete control and interlock logic;
(2)Sequential function diagram
It provides the overall structure and is coordinated with state location processing or machine control applications;
(3)Function block diagram
It provides an efficient development environment and is particularly suitable for process control applications;
(4)Structured text
This is a programming language similar to that used for computers,which is suitable for complex algorithms and data processing;
(5)Instruction list
It provides an environment for optimizing coding performance,much like assembly language.
编程语言最为复杂,多种多样,看似相同,但不通用。最常用的可以划分为以下5类编程语言:
(1)梯形图
这是PLC厂家采用最多的编程语言,最初是由继电器控制图演变过来的,比较简单,对离散控制和互锁逻辑最为有用;
(2)顺序功能图
它提供了总的结构,并与状态定位处理或机器控制应用相互协调;
(3)功能块图
它提供了一个有效的开发环境,并且特别适用于过程控制应用;
(4)结构化文本
这是一种类似用于计算机的编程语言,它适用于对复杂算法及数据处理;
(5)指令表
它为优化编码性能提供了一个环境,与汇编语言非常相似。
Sorensen DLM150-4 DC power supply with factory calibrat
SORENSEN POWER SUPPLY SCB306A-NX1 SCB306ANX1 SCB306A /
SORENSEN XANTREX DCS60-18 DC POWER SUPPLY 60V 18A
Sorensen DLM 60-10 / DLM60-10
SORENSEN DLM60-10M9G POWER SUPPLY 0-60V 0-10A * GPIB #6