Due to the virtualization and networking of the communication mechanism, it is difficult to economically and effectively isolate the secondary circuit during the maintenance of the secondary circuit in the smart substation. In this paper, a one-key isolation system for secondary devices of smart substations is established, and the software and hardware configuration schemes required by the system are given. Firstly, it introduces the research theory method, utilizes the non-extractable extensible markup language analysis method to quickly decouple and analyze and calculate the IEC 61850 SCD configuration file of the smart substation, and converts the isolation range problem in the process of maintenance and reconstruction of the station into event diffusion problem in graphic signal processing, and the visualization display of complex data processing algorithms is realized through graph signal processing technology. Then, the corresponding rules between SV link, GOOSE output link, GOOSE receiving link and soft pressure plate are given to clarify the range of isolation during maintenance. Finally, the visual generation of the sequence of safety measures for device isolation can visually display the isolation of the secondary circuit and assist on-site personnel to carry out maintenance work.