山东交通学院 PLC课程设计
Abstract
Electrical control and PLC curriculum design is mainly based on the control experiment of PLC, combined with theoretical knowledge so as to have a better understanding of it, so that better use at work. Programmable logic controller (PLC) the advantages of computer functions, universality and good flexibility and relay control system simple and easy to understand, easy to operate, low price etc. together, so it is a kind of adaptation and general control device for industrial environment. Now the programmable controller and the original control system, increased the arithmetic operations, data conversion, process control, data communication and other functions, can complete large and complex control tasks. The programmable controller is one of the pillars of industrial automation technology, in industrial automatic control field occupies a very important position. S7-200 PLC is a small PLC, the basic structure of the host is integral, the host has a certain number of input / output (I/O), a host is a system. It also can be extended, if not I/O points, you can increase the I/O extension module. S7-200 PLC powerful feature that allows it to operate independently, or connected into a network can realize complex control functions. Because of its compact design, good scalability, low price, abundant function module and powerful instruction system, makes the S7-200 PLC can be almost perfect to meet the control requirements of small scale.
This course is designed to achieve three design, they are S7-200 manipulator control based on PLC, temperature and humidity monitoring system based on EM235, the control of stepping motor based on PLC.
Key words: PLC EM235 Manipulator stepper motor
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山东交通学院 PLC课程设计
第一章 基于PLC 的机械手控制（天煌）
1.1总体设计要求
机械手工作示意图如下：
控制过程如下：
开始时，机械手处于原始位置，且为放松状态，则Y0亮，Y7亮。按下启动按钮后，机械手开始顺序动作：
1、机械手下降：延时1秒后，Y0灭，Y9亮，到下限位时，按S3,则Y9灭，
Y1亮。
2、机械手夹紧：延时3秒后，Y7灭，Y6亮，
3、机械手上升：Y1灭，Y8亮，到上限位后，按S4，则Y8灭，Y2亮， 4、机械手右行：Y2灭，Y10亮，到右限位后，按S5，则Y10灭，Y3亮， 5、机械手下降：Y3灭，Y9亮，到下限位后，按S3，则Y9灭，Y4亮， 6、机械手放松：延时3秒后，Y6灭，Y7亮，
7、机械手上升：Y4灭，Y8亮，到上限位后，按S4，则Y8灭，Y5亮， 8、机械手左移：Y5灭，Y11亮，到左限位后，按S6，则Y11灭，Y0亮，回
到原始位置。
1.2设计目的
（1） 了解PLC控制系统设计以及软件程序设计加深对PLC的认识。 （2） 了解机械手的构成以及工作原理
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山东交通学院 PLC课程设计
（3） 学习PLC的硬件连接与机械手的接线
（4） 熟悉PLC编程的工作原理、规则、技巧和方法等
1.3 I/O分配
输入定义 启动 循环切换 完全停止 SQ1 SQ2 SQ3 SQ4 一次停止 输入端口 I0.0 I1.0 I0.1 I0.2 I0.3 I0.4 I0.5 I0.6 输出定义 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 输出端口 Q0.0 Q0.1 Q0.2 Q0.3 Q0.4 Q0.5 Q0.6 Q0.7 1.4梯形图及STL语句
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山东交通学院 PLC课程设计
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