Abstract: In this paper, a fault in mechanical characteristic test of circuit breaker caused by the failure of shield cable was analyzed. As well, the whole process of cause finding and problem solving are introduced, for reference.

Key words: circuit breaker, mechanical characteristic test, shield cable

摘要： 分析了一例因控制电缆屏蔽层未做防护，屏蔽层和二次插把外壳短接，导致地刀动触头侧接地，导致断路器机械特性测试结果异常的故障，介绍了故障原因查找过程和故障排除方法。

关键词: 断路器, 分合闸特性测试, 屏蔽线