Abstract: In order to address frequent failures caused by aging equipment in the Andritz SAT250 monitoring system used by substations, the heavy workload on the AK master control unit, delayed remote signaling uploads, non-direct acquisition and transmission of remote control data, and the unavailability of spare parts for discontinued measurement and control devices, it is necessary to carry out a systematic transformation of the substation comprehensive automation system. During the transformation transition phase, issues such as substation operation monitoring, prevention of misoperation locking, and dispatch data forwarding are critical. Taking the comprehensive automation system transformation project of a 500 kV substation as an example, this paper analyzes the data transition between the new and old monitoring systems, the dispatch remote control data upload, and the misoperation prevention locking scheme during the transformation process. In conjunction with the actual project, the design scheme is optimized, and a transition plan is proposed that allows the five-prevention system to communicate with two monitoring systems simultaneously to ensure complete misoperation prevention locking. Furthermore, the SAT250 monitoring remote control is connected to the new remote control system, achieving complete uploading of substation remote control data and ensuring a smooth transition and safe and stable operation during the transformation period.