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Low voltage cables refer to power cables with a working voltage below 1kV, composed of cores, insulation layers, and protective layers. Compared with high-voltage cables, low-voltage cables also have different process structures and application ranges. Similarly, they are carriers for conducting electrical energy, and their applications are ubiquitous. So in daily use, if a cable fault occurs, how can we solve and repair it as soon as possible? When a cable fault occurs, we will first find a solution to the problem and restore operation. In addition, we will analyze the cable fault and analyze the specific causes. According to data from the after-sales service department of Dingsheng Electric Co., Ltd., there are two main causes of low-voltage cable faults. First, external factors cause damage to the outer insulation, and grounding faults are caused by moisture. Second, improper joint handling leads to short-circuit faults caused by moisture. After a cable fault occurs, it is necessary to use a multimeter or electronic megohmmeter to analyze the current fault situation through data. The specific method is to use a 2500-volt digital megohmmeter to measure the insulation resistance values between phases and between phases and ground. Through the elimination method, find out which phase has the cable fault. After determining the fault phase, use a multimeter to measure the grounding resistance value. If the measured resistance value is greater than 200 ohms, the "step voltage method" can be used. Otherwise, use the "high-voltage flashover method". It should be reminded that if there is no voltage, this process is easier to judge. The step voltage method is suitable for cable faults at all grounding fault voltage levels. It is a method to find cable faults by using the voltage between two legs around the grounding current input point. The specific wiring method is to connect the red clip of the power cable fault detector to the faulty phase of the tested cable, and the black clip to ground, then connect the path induction magnetic rod and step voltage sampler. After the host is started, it sends electromagnetic pulses and short synchronization signals. By searching the magnetic rod receiver along the road surface, the cable path can be accurately detected, and then cable fault location is carried out along the searched path. The specific method is that the left and right ends of the step voltage sampler are marked with red and green marks, and the indicator also has corresponding indication marks. Insert the step voltage sampler into the soil. The red and green directions of the indicator represent the direction of the cable fault point. If encountering a hard road surface, watering can also make precise measurements. When you move the indicator to the right, the fault point can be determined, and so on. Return to Sohu,