基于西门子S7-200PLC自动饮料售货机控制系统BeverageVendingMachinesPLCControlSystembasedonSiemensS7-200Series总计毕业设计____39___页表格____3____个插图____10___幅I摘要本论文是基于西门子S7-200系列PLC进行自动饮料售货机控制系统的设计的。本文介绍了PLC的硬件基本组成,特点以及工作原理。阐述了自动饮料售货机的来源,发展及系统设计的基本原理及工作流程。在PLC梯形图的编写时,文中采用的是西门子PLC梯形图专用编译软件4.0版本的STEP7来进行编写,并完成了PLC外部接线图。利用PLC控制的自动饮料售货机提高了系统的稳定性,且逻辑上保证无或者尽量减少漏洞,使自动售货机能够长期稳定运行,不需要经常有人维护。关键词:自动饮料售货机PLC梯形图西门子I摘要ABSTRACTThedesignofAutomaticBeverageVendingMachinePLCControlSystemisbasedonSiemensS7-200series.ThepaperintroducesthebasicstructureofPLC,characteristicsandworkprinciple.InthePLCtrapezoidalchartcompilation,thispaperadoptstheSiemensPLCladderspecialcompilersoftwareversion4oftheSTEP7towrite,andcompletedthePLCexternalwiringdiagram.ToimprovethestabilityofthesystembyusingautomaticbeveragevendingmachinePLCcontrollogic,andensurenoorlittleloopholes,thevendingmachinecanhavealong-termstableoperation,notoftenneedsomeonemaintenanceKeywords:automaticbeveragevendingmachine;PLC;ladderdiagram;SiemensII目录摘要....................................................................IABSTRACT..................................................................II前言....................................................................1第1章可编程控制器PLC..................................................31.1可编程控制器的产生和发展.............................................31.1.1可编程控制器的概述.............................................31.1.2PLC的产生原因.................................................31.1.3PLC的发展前景.................................................41.2可编程控制器的结构和工作原理.........................................41.2.1PLC的工作原理.................................................41.2.2PLC的循环扫描.................................................51.2.3PLC的硬件组成.................................................61.2.4PLC的编程语言.................................................71.2.5PLC的特点.....................................................71.2.6PLC的主要功能.................................................81.3PLC的选型原则及选型方法.............................................9第2章自动饮料售货机的系统设计.......................................122.1自动饮料售货机的控制要求............................................122.1.1自动饮料售货机的控制要求......................................122.1.2自动饮料售货机的相关说明......................................132.1.3定时器........................................................142.1.4数学运算指令.................................................152.2自动饮料售货机I/O点的分配.........................................162.3自动饮料售货机的外部接线图.........................................172.4自动饮料售货机梯形图的编写.........................................172.4.1梯形图........................................................172.4.2自动饮料售货机设计的梯形图...................................18结语.................................................................19参考文献.................................................................21程序图....................................................................