Cable on-line monitoring method and device

The invention relates to a cable on-line monitoring method and device, and the method comprises the steps: obtaining the waveform of a current in a power supply cable, wherein the amplitude of the waveform is a current value; determining whether the waveform has transition or not; and when transition exists in the waveform and the current value of the waveform after the transition is zero, determining that a short-circuit fault exists in the power supply cable, so that fault monitoring is achieved, and the operation and maintenance efficiency of a power system is improved. 本发明涉及一种电缆在线监测的方法及设备，该电缆在线监测的方法包括：获取供电线缆中的电流的波形，其中，所述波形的幅值为电流值；确定所述波形是否存在跃迁；当所述波形中存在跃迁，且在所述跃迁之后的所述波形的电流值为零时，确定所述供电线缆中存在短路故障，实现故障的监测，提高电力系统的运维效率。