The Design And Implementation Of PLC Data’s Remote Monitoring And Control System Based On Embedded 3G Network

Whether it is able to communicate and monitor the equipments have been saled remotely is very important and has great significance for manufacturers. The remote communication and monitoring system can shorten the time of discovering the devices’ errors; improve the efficiency of equipments’maintenance, reduce the costs of equipment maintenance. With the rapid development of Internet technology and embedded terminal technology, the traditional industrial automatic control technique gradually fusion with the network technology and the remote communication and monitoring technology based on network gets more and more attentions. With the 3G network technology having become more mature, the developments of wireless remote monitoring system are accelerated, which has solved the problems because of the possibility about arrangement of network and limitation of remote monitoring system and the low transmission rates problems of GPRS wireless network. According to this situation, this paper introduces the design of remote monitoring system based on 3G network of industrial control equipment PLC, the mainly work are summarized as follows:1, the research about HostLinkFINS protocols. PLC has a variety of communication methods to communicate with external device, by comparing several communication methods’advantages and disadvantages, we choose the serial communication as the best communication mode. We importantly analysis the protocol and format based on the serial communication protocol HostLinkFINS communication protocol, master the related communication instruction, lay the foundation for the realization of remote monitoring.2, the design of 3G terminal hardware circuit. According to the project requirement analysis, we designated the scheme of monitoring system. We determine the Tiny6410/ARM11 as the core processor and designated the scheme hardware circuit design, for example, we designed the interface position according to the actual application environment choose the function modules according to the performance requirements and reliability, security and anti-interference ability, cost. The main function modules include power supply module,3G module, GPS module, UART module, RTC module, SD module, Ethernet module and so on. When Scheme had been determined, we drawn schematics, PCB circuit diagram, and then welded and tested on the hardware circuit board, to ensure the working of the hardware circuit of 3G terminal normal and stable.3, the 3G termination’s underlying software and application software design. For the underlying software, the mainly work is the system level program customization of embedded system, including bootload transplantation, kernel configuration and transplantation, Linux system cutting and configuration of the transplantation. For application software design, the mainly work is to complete the data transparent transmission and processing, except this, we also design the heartbeat packet function, GPS function, data encryption function and so on, the overall application is designed into a multi-threaded program.4, the PC software design. The PC software includes the design of server and client, the server is the data processing center, which is responsible for receiving instructions and processing the requests, including forwarded instruction, data transmission, uploading and downloading program, database operation and so on. Client design is aimed at the user, which designed related interface and function according to the monitoring function requirements. The whole design structure using C/S mode, the Java programming language and system design involves a variety of network programming, multi thread programming, data structures and algorithms of technical knowledge to complete PC desired function.In order to validate the system functional correctness,we debug the whole system with PLC, the 3G terminal, server and client. We test each function one by one according to functional requirement. Through the functional testing, the monitoring system can fully meet the needs of the project.