Abstract: Firm Sys is the first and currently the only digital nuclear safety instrument and control system platform in China, which has been developed, qualified and applied. Based on ACPR1000, Yangjiang Nuclear Power Plant（units 5 and 6） is the first nuclear power plant to adopt Firm Sys platform to realize the function of reactor protection system. According to the requirement of related standards and regulations, the reactor protection system should be periodically tested. The periodic test should cover the whole protection system and it is closely associated with the diagnosis design and the structure of protection system. Additionally, the effect on the system safety functions need to be concerned. The periodic test design has been one of the key design technologies for digital protection systems. Based on safety analysis method, a complete set of periodic test solutions are presented in this paper, which meet the requirements of standards and regulations. Compared with the CPR1000 project, it simplifies the design of the protection system, optimizes the operation of test personnel, and improves the periodic test scheme of the operation program.