安全系统的结构不再重要

The Architecture of Safety System is No More Important

ABB致力于安全解决方案已整整有30年的历史。当ABB在上个世纪70年代末向欧洲北海引入其首个安全系统时,系统的内部结构是一个十分重要的话题。系统的提供者展示其设计满足安全相关应用所需完整性等级的手段,主要是通过解释系统内部结构的冗余机制。随之而来的如2选1(1oo2),3选2(2oo3)投票、双重化冗余(DMR)、三重化冗余(TMR)和四重化系统等是术语为市场广泛接受(未必为大家完全理解),并至今出现在安全要求规范和供应商的手册。随着国际功能安全标准IEC61508和IEC61511的出现和推广,术语"安全完整性"得到全面而完善的定义,并促进全新一代的安全系统的开发及应用;与此同时诸如DMR,TMR和四重化的概念已不再适用。本文作者认为对新一代安全系统而言基于其硬件结构的归类已不再具有代表性,应当加以避免。

ABB have been working 30 years on safety business globally.When ABB introduced its first Safety systems into the North Sea back in the late 70＇s,the internal architecture of the system was of great importance.The way in which the systems builders demonstrated that their design could achieve the levels of integrity necessary for safety related applications was mainly by explaining how the internal structure provided redundancy.Over the years terms such as 1oo2,2oo3 voting,DMR,TMR and Quad systems have become accepted（if not fully understood） in the market and are still appearing in requirement specif ications and suppliers brochures.However,since the advent of the IEC 61508 and IEC 61511 standards,the term ＂Safety Integrity＂ is fully defined and has lead to a new generation of system where the terms DMR,TMR and Quad do not apply and are irrelevant.The authors argue that categorizing the new generation of systems by its hardware architecture is no longer relevant and should be avoided.