核电站反应堆控制棒束的无损检查对核安全意义重大，以往对磨损、肿胀和裂纹等典型缺陷的分析较多，而实际应用中，信号采集设备本身、现场环境等因素引起信号异常的现象也时有发生。介绍了信号采集设备的工作原理，分析了现场检查过程中出现的三种异常信号，并找出了其产生原因，可为设备的调试和故障排除提供借鉴。

The nondestructive examination of rod cluster control assembly is important to nuclear safety. There were many analyses about the typical defects of wear, swelling and crack, but little was introduced about the abnormal signals caused by the acquisition equipment and on-site environment which also occured in practical applications. This paper introduced the working principle of the acquisition equipment, analyzed three kinds of typical abnormal signals in the process of on-site inspection, found out its cause and had certain reference value for the debugging and troubleshooting of the equipment.