安全计算机平台的主备切换板设计

介绍一种基于安全继电器的主备切换板。两个继电器前后节点互相串接实现互斥,不得同时吸起。当安全平台系间通信双通道均断开时,系统根据继电器状态信息进行切系操作,可防护安全平台潜在的双主风险。对主备切换板的硬件设计、软件设计和安全通信协议设计进行说明,其安全完整性等级达到SIL4级。

Design of Host and Backup Switching Board for Safety Computer Platform

This paper introduces a kind of host and backup switching based on safety relay. Front and back contacts of two relays are connected in series with each other to achieve mutual exclusion with each other to achieve mutual exclusion. When both communication channels among safety platforms are disconnected, control mode switching is operated according to relay status. Therefore, potential dual host risk of safety platform is protected. The hardware design, software design and safety communication protocol design of host and backup switching board are also illustrated. The safety integrity level of switching unit is SIL4.