With the rapid development of Ethernet technology, Ethernet has become a new hotspot in the industrial control. So, the development of EPA Master Controller is a big significance for EPA Control System which based on EPA standards. EPA Master Controller is a platform that connects various protocol fieldbus modules, I/O modules and software for the upper. In the EPA system, it is a field device that consistent with EPA protocol. It communicates with upper engineer and operator stations. Also, data is transferred between field bus module, I/O module and the Controller. More, it’s responsible for signal acquisition, processing and control.