The so-called low-voltage cable refers to a power cable with a working voltage lower than 1kV. The low-voltage cable is composed of a core, an insulating layer, and a protective layer. Compared with high-voltage cables, low-voltage cables also have different process structures and application ranges. Similarly, they are all carriers for conducting electrical energy, and their application scope is ubiquitous. So in daily use, if a cable fails, how can we solve and repair it as soon as possible? When a cable fails, we will first find a way to solve 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 Power Co., Ltd., there are two main reasons for low-voltage cable faults. First, external factors cause damage to the external 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 an electronic megohmmeter to analyze the current fault situation through data analysis. 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 of all grounding fault voltage levels. It is a method that uses the voltage between two legs around the grounding current input point to find cable faults. The specific wiring method is to connect the red clip of the power cable fault detector to the fault phase of the tested cable, ground the black clip, and then connect the path's induction magnetic rod and step voltage sampler. After the host is started, it sends electromagnetic pulses and short synchronization signals. By searching along the road surface with the magnetic rod receiver, 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 you encounter a hard road surface, watering can also measure accurately. When you move the indicator to the right, you can determine the fault point, and so on. Return to Sohu,
