Abstract: Aiming at the problem of stopping production for communication failure in the belt conveyor protection system, this paper analyzes the characteristics of the query bus and control bus of the protection system, and proposes a grouping communication and bus redundancy mechanism based on the causes and mechanisms of communication failures. The bus redundancy mechanism does not change any hardware and utilizes communication detours to ensure normal communication of the system, at the same time to alert the location and type of failures. By conducting communication tests on 10 devices along the single belt protection system, including multiple failures on the query bus, single failure on the control bus, and composite faults on the query/control bus, the problem of single failure stopping production was solved, and the communication robustness of the system was improved.