This paper uses electromagnetic transient calculation program ATP to test the influence of lightning incoming surge along transmission line on stand-by circuit breaker and disconnecting switch. As a result, arresters should be installed to protect stand-by circuit breaker and disconnecting switch. 介绍了利用ATP电磁暂态仿真计算程序分析验证线路雷击侵入波对备用状态下的线路断路器及隔离开关的影响,提出了处于这种状况下的隔离开关和断路器必须加装避雷器保护的观点。