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Two key points for DCS technical supervision: 1. The DCS performance has not been thoroughly tested; the control system is aging, and no comprehensive DCS performance tests have been conducted. There is a lack of performance metrics such as network load rate, system response time, interference resistance, and SOE resolution. Article 9.1.1 of the \"Countermeasures\" stipulates that the configuration of the distributed control system shall meet the monitoring requirements under any operating conditions of the unit (including emergency fault handling). Parameters such as the CPU load rate of the control station and human-machine interface stations, the system network load rate, the communication load rate between the distributed control system and other related systems, the control processor cycle time, the system response time, the resolution of the Sequence of Events (SOE) recording, the interference resistance, the quality of the control power supply, and the GPS clock must all meet the requirements of relevant standards. Technical requirements: (1) The SOE resolution must not be greater than 1ms ； (2) The clock output signal accuracy of the GPS system should be 1 μs. Clock synchronization between the GPS and DCS systems should take place every 1 second, with a synchronization accuracy of 0.1 s; the clock error for each system should be less than 2 μs. Currently, the accident recall systems (SOE) in many power plants are not functioning properly; the timing of SOE signals varies across different DCS cabinets, resulting in the loss of the accident recall function when the unit trips, and thus the loss of this valuable tool for accident analysis. It not only significantly reduced the accuracy of accident analysis but also severely affected the speed at which the unit could resume operations. 2. Inadequate DCS management: the operating environment does not meet the requirements; there is excessive dust inside the cabinets, fan failures, messy wiring, and the cable openings are not properly sealed. Technical requirements: (1) Redundant configuration: The controllers of critical systems should be configured redundantly; in the event of a failure of the active controller, the system should be able to automatically switch to the redundant controller and issue an alarm ； (2) Load rate: The controller’s load rate shall not exceed 60% ； The operator station load rate shall not exceed 40% ； Communication load rate: it should not exceed 20% for Ethernet, and not exceed 40% for other networks ； (3) Periodic testing: The DCS system after maintenance or upgrading should undergo DCS performance testing ； ● Environmental requirements: Temperature 15-28℃ ； Humidity 45-70%.