Informational Note No. 1 for the definition of arc-flash hazard in National Fire Protection Association (NFPA) Standard 70E-2015 states, "Under normal operating conditions, enclosed energized equipment that has been properly installed and maintained is not likely to pose an arc-flash hazard." Table 130.7(C)(15)(A)(a) of the standard instructs that arc-flash personal protective equipment (PPE) is not required for normal operation of a circuit breaker, switch, contactor, or starter if the equipment is properly installed, properly maintained, equipment doors and covers are closed and secured, and there is no evidence of impending failure. This article reviews three electrical equipment failures during substation circuit breaker operations where if personnel had followed the guidelines just described, they could have been seriously injured during these failures due to the arc-flash energy released at the time of the fault.

中文翻译：

---

设备在正常运行条件下运行的故障

美国国家消防协会 (NFPA) 标准 70E-2015 中电弧闪光危险定义的信息说明 1 指出，“在正常操作条件下，正确安装和维护的封闭带电设备不太可能产生电弧- 闪光危险。” 标准的表 130.7(C)(15)(A)(a) 指示，如果设备正确，则断路器、开关、接触器或启动器的正常操作不需要电弧闪光个人防护设备 (PPE)安装、正确维护、设备门和盖已关闭并固定，并且没有即将发生故障的迹象。本文回顾了变电站断路器操作期间的三个电气设备故障，如果人员遵循刚才描述的准则，