Application And Research Of PLC In The Thermometer Detection System

Currently, the advanced technology of testing the quality of the thermometer is still using a semi-manual inspection method.So aiming at the the problems of the self-regulation in the automatic detection of thermometer, this project designed an automatic thermometer detection system which is based on PLC(Programmable Logic Controller, PLC) technology, achieving the automatic adjustment of the height of detection thermometer.This project mainly studies the method of the PLC driver stepping motor and then controlling the position of the thermometer.Taking the position of the thermometer as the object of study,designing and developing the control system of the thermometer detection device.This control system is divided into upper and lower computer.Lower machine uses the FX2 N series PLC as the control unit, and upper machine communicate with the lower machine by PC Serial port to control lower machine achieving the regulation of the thermometer position by driving stepper motor.This control system achieves these operations of controlling the position of the thermometer which includes "starting to root from the origin position, rising and falling with different speeds in a certain distance, creasing rapidly at the bottom and the top, stopping",and eliminating all the demand of the control system.The system is used to the Municipal Quality Supervision Bureau.Practice has proved that is can meet the needs of Automatic change of the temperature position and having certain application value.