摘要
通过对一个PLC控制系统的分析，说明在PLC的应用中，改变传统继电器控制电路的思考方法，充分利用PLC内部资源，可以进一步节省投资，提高可靠性和自动化程度。
By analysing the PLC control system the author has introduced an idea. If the userchanges his habitual thinking method about the traditional relay control circuit and makes full useof the restricted resource of PLC, he can save investment, improve reliability and raise the level ofautomation.
关键词
控制系统
可编程序控制器
应用分析
control system
programmable controller
application analysis
