Based on the constitution and the conception of safety and availability of ESD system,the article discusses the logic controller of ESD system and its input and output loops on the safety and availability.

• 从紧急停车系统的构成及安全性与可用性的概念出发,讨论了紧急停车系统逻辑控制器、输入输出等各环节的安全性与可用性。