【摘要】 以果蔬真空预冷机的控制系统为例,分析其结构和工艺原理,采用小型PLC代替传统的继电器控制,进行了PLC选型和程序设计,实现了果蔬真空预冷机的PLC自动控制,从而提高了预冷机的可靠性和自动化程度,对通用真空预冷控制系统的设计具有借鉴意义。更多还原

【Abstract】 The control system of a vacuum cooler for fruits and vegetables was designed based on S7-300 PLC(Programmable Logic Controller).The traditional relay control system was replaced by the small-scale PLC.This new PLC control system can control the refrigerating machine,the vacuum cooler,a series of valves automatically.As a result,the reliability of the vacuum cooler was improved.更多还原