可编程序控制器通用数据采集方法的研究

文中介绍一种支持可编程序控制器(PLC)的温度、电流和电压数据采集模块,该模块采用隔离标准异步输出接口,设计适合PLC普通开关量输入采集数据的无条件半字节选通输出、无条件字节选通输出、请求半字节选通输出、请求字节选通输出等时序。文中叙述了PLC程序的数据采集方法,给出了使用西门子S7-226采集数据的程序。

A kind of acquisition module used to collect data of temperature,current and voltag e is introduced in this paper,which can transfer the data to PLC via isolate standard asynchronous output port.The schedul-ing is desig ned to input data to PLC throug h common switches,including unconditional half-byte strobe output scheduling ,unconditional byte strobe output scheduling ,request half-byte strobe output scheduling ,and request byte strobe output scheduling .The data collection methods of PLC prog ram are discussed,and the data-collection prog ram applied to Siemens S7-226are presented.