Design And Developments Of EPA Interface For Industrial Field Instruments

Fieldbus is the dominant technology in the field layer of the current industrial control networks. But the lack of a unique international standard and low communication rate are becoming the obstacle of its further development and application. This situation leads industry to adopting Ethernet into fieldbus standardization. Many industrial Ethernet protocols are presented one after another, such as HSE (High Speed Ethernet), EPA (Ethernet for Plant Automation), PROFINET, Modbus/TCP and so on. The EPA standard is the first fieldbus standard, whose IP (Intellectual Property) belongs to our country entirely. Further more, It is embodied by IEC61158 (Edition 4) formally. It is an international standard admitted by IEC.The EPA field instruments are the important parts of the EPA control systems. Low power consumption, reliability and real time are their special requirements. So the design and developments of the field intelligent instruments is one of the key technologies of the EPA system.Based on the in-depth analysis of the developing trend and design idea of the current industrial instruments, the design and developments of the EPA interface in industrial instruments are presented in dissertation. It is used to change the traditional instruments to the EPA intelligent instruments.The in-depth and fine analysis and expatiation of the software and hardware design of the EPA interface are introduced in the dissertation. Based on the requirements of current industrial instruments design, many low power consumption and reliability design methods are adopted synthetically. The comprehensive analysis of the system power consumption is processed based on the expatiation of every low power consumption design methods. Based on the explicit analysis of the principles and methods of the component level and the system level reliability design, the detailed design process is forwarded in allusion to the reliability design methods adopted in EPA developments.In the EPA interface design, field instruments are asked to provide information about device itself, process diagnosis and management, besides the process measurement information. The design method of using function blocks to back the implementation of the instruments functions is forwarded.The successful application of the EPA interface in traditional instruments is a good reference in design and development of EPA instruments.