Abstract: AzS350U axle counting system is used for certain domestic Metro Line 6, and which is used as the train detection equipment under the backup mode of signal system. In the CBTC mode, the axle counting fault can be immediately cut off by the zone controller (ZC) and become a brown light band, without affecting CBTC train operation. However, it is found in the actual operation process that when the host modular block in the axle counting room is crashed,  there are cases where the corresponding axle counting sections cannot be normally removed by ZC, resulting in the expansion of the fault. In view of the defects in the interface part of the system, this paper makes an in-depth analysis combined with the principles of axle counting and signal system, and proposes to modify the maximum allowable communication transmission time set by the axle counting system, for fundamentally solving the impact of this defect on normal operation.

Key words: axle counter crashing, zone control, maximum communication transmission time

摘要： 国内某地铁6号线路采用AzS350U计轴系统，作为信号系统后备模式下的列车检测设备，在基于通信的列车控制（CBTC）模式下，计轴故障能够被区域控制器马上切除变为棕光带，不影响CBTC列车运行，但是在实际运营过程中发现，在计轴室内主机组匣死机时，对应的计轴区段曾发生不能被ZC正常切除的情况，导致故障的扩大化。针对该系统接口部分的缺陷，结合计轴以及主信号系统的原理进行深入分析，提出通过修改计轴系统设置的最大允许通信传输时间的方式，从根本上解决该缺陷对正常运营的影响。

关键词: 计轴死机, 区域控制, 最大通信传输时间