The Design Of Cold Temperature Monitoring And Information Management System

In recent years, food safety incidents occur frequently. In order to improve the supervision of food producing, storage and transportation, government has promulgated a number of policies and regulations. New technologies of food detection also emerge as the times require. To fulfill the needs of supervision in small and medium-sized food storage centers or supermarkets, this study designs a cold storage temperature monitoring and information management system, which realizes the functions including real-time online monitoring of cold storage temperature, information query, display of history temperature curve, abnormal temperature warning. To maintain the food in cold storage at specified temperature, the system provides technical supports to ensure the safety of food stored in refrigerated or frozen process.The cold storage temperature monitoring and information management system consists of two parts:a real-time online monitoring device and an information management of computer software. The monitoring device and the computer are connected based on RS-485Bus.Monitoring device includes five main parts:first is a micro controller module using Renesas Electronics uPD78F0495single chip and an embedded program flashed in the ROM of the single-chip. Second is a circuit of LCD touch screen display, which realizes the interaction between operators and computers, with the functions of command input and data and curves displaying. The third part is a circuit of the temperature data acquisition, through the analog input port of the single-chip, it collects temperature measurements through sixty-six channels, including sixty-four channels of cold storages, one indoor channel and one outdoor channel. The fourth part is a circuit of GSM-SMS transceiver, it sends text messages to the designated mobile phone when the temperature measurements exceed the warning limits. the fifth part is a circuit of communication based on RS-485Bus, it realizes the real-time data transmission between the computers and the monitoring devices, and carries the parameter settings and commands.The computer information management software mainly completes some functions, including receiving uploaded channel information of cold storages from the monitoring device, receiving the temperature measurements and storage data of each channel, display the temperature data and temperature curves in specific time and storage, setting up the parameters for the monitoring device. The person on duty can operate the real-time monitoring remotely, and query the historical information in the office.The content of this thesis is as follows.The first part is the overall structural and functional description of the system.The second part gives the designing of the monitoring device hardware and the embedded software, which is the key content of this thesis.The third part is the designing and implementation of the computer information management software.In brief, as the increasing importance of food safety and the more strictly supervision of food safety storage, the cold temperature monitoring and information management system in this research has a broad application prospect.