Application of Modbus Protocol in the Automatic Safety Device

The traditional HMI ( human-machine interface ) of automatic safety device is lack of beauty and friendship. With the development of smart grid, there are more and more high requirements of the HMI. The automatic safety device was divided into the HMI module and the device main body. An industrial touch screen which supports for Modbus protocol, was selected as the HMI module of the automatic safety device. The HMI data was extracted into the standard data of Modbus protocol, and mapped to the unified address space of Modbus protocol. Modbus RTU mode was used to achieve the data communication between the HMI module and the device main body. This method not only makes the display content richer, interface more user-friendly, but also makes the product development cycle shorter and the product more scalable.