Remote Terminal Unit Based On Wireless Teletransmission Module

China is large country with vast territory and resources,flooding and drought are becoming more frequent and severe relatively,which has a great impact on both agricultural production and water industry.Therefore,it is particularly important to monitor hydrological information in relevant regions.Remote monitoring terminal has found an increasingly wide utilization in the water industry with the rapid development of electronic technology.The primary research topic in the intelligent manufacturing of agricultural water resources is to find a method which could achieve stable and efficient access to on-site agricultural and water resources information,realize uninterrupted monitoring and early warning all day by cooperating with remote operation platform.In this case,the hydrological telemetry system emerged as the times require.Firstly,hydrological telemetry system would collect and process various hydrological information of telemetry station via RTU.Secondly,hydrological information would be stored in specific location according to the different message type and time quantum by RTU.RTU would upload the detailed information which required by the central station after a certain time interval,alarm or the requirement of query instruction from the central station.Finally,The central station analyses and calculates the field information,then displays it on website for the staff.In this process,the primary task is to collect and upload raw data steadily.Nowadays,the rapid development of wireless communication technology,sensor technology and computer control technology provides technical support and the oretical fulcrum for the progress of intelligent acquisition terminal system.This paper focuses on the application requirements of data acquisition terminal in agricultural and water.resources.The hardware structure is designed and the embedded software of each module is developed for improving the instability,high power consumption and high maintenance cost which appeared continually on current Frequently-used telemetry terminal.The design introduced in this paper takes STM32L433VCT6 as the core,including a variety of working modes to adapt to different field environments.The wireless communication of telemetering terminal adopts 4G transmission module SIM7600C.The external sensors such as rainfall and water level collect real-time data of hydrological field.The data are stored by ferroelectric memory FM24CL16 and NOR FLASH,RTU could monitor the real-time hydrology data,at the same time,on the one hand,RTU could monitor its own supply voltage to avoid overvoltage and undervoltage by ADC,on the other hand,the terminal is equipped with self-designed electricity measurement module,which is used to monitor the working condition of pumps in dangerous situations.In order to meet various environments and more on-site requirements,4-20mA circuit,485,SPI and multi-channel switching input are reserved on RTU.The terminal could achieve ultra-low power consumption while satisfying the requirement of stable information collection and uploading.Besides,the wake-up buttons and ID access cards on RTU greatly facilitate the later maintenance for the field personnel.At the same time,the design is equipped with relevant remote query and control software for uninterrupted data acquisition and monitoring throughout the dayIn addition,a mature product which was designed for practical application,also demand to meet the agreement of relevant departments,this design consummates the national standard water agreement 651 and 206 protocols while completing the functional requirements,and it could display in the server interface clearly for the users to query and monitor hydrological information through software demo.