东风4 型机车是我国铁路运输生产的主型机车 ,在使用中经常出现这样那样的故障 ,特别是电气方面故障较多。这就要求乘务人员、检修人员、专业人员对线路线号熟悉 ,及时判断、查找、处理故障 ,保证机车正常运行。本人对主电路线号记法按主要部件、自然序号摸出一点规律仅供参考 Dongfeng 4 locomotive is the main locomotive of China’s railway transport production, often appear in use such a fault, especially in electrical fault more. This requires crew, maintenance personnel, professionals familiar with the line number, promptly determine, find, handle the fault, to ensure the normal operation of the locomotive. I remember the main circuit line number according to the main components, the natural number to find a little law for reference only