Power cables will inevitably be damaged during long-term operation, causing the cables to fail to transmit power normally. The reasons include the overall damage caused by external force, the burning of the metal core caused by the short circuit of the equipment, the influence of high voltage on the insulation layer, and the influence of temperature and humidity on the cable insulation layer.
Power cables will inevitably be damaged during long-term operation, causing the cables to fail to transmit power normally. Reasons include overall damage caused by external forces, metal core burnout caused by equipment short-circuits, the influence of high voltage on the insulation layer, the long-term influence of temperature and humidity on the cable insulation layer, and the oxidation of the insulation layer. Many factors such as cable failure. From a professional point of view, cables are generally divided into two categories: short circuit, open circuit, low resistance fault, high resistance flashover and leakage fault.
According to the principle of radar ranging, the low-voltage pulse method sends pulse signals to the cable at the test end. When the characteristic impedance does not match (the cable is short-circuited), a reflected wave will be generated, and the incident and reflected waveforms will be collected and displayed on the screen. At this point, we can calculate the distance from the fault point to the test terminal based on the propagation speed of the radio wave in this cable.
For cable fault finding, set the parameter to low-voltage pulse waveform output, connect the red and black clamps of the cable fault tester to the fault phase of the tested faulty cable and another good phase or cable ground, and click the "sample" button. The instrument automatically acquires the incoming data, and the waveform is displayed on the screen at the same time. The operator can continuously adjust the "position adjustment" and "amplitude adjustment" knobs according to the waveform amplitude and position displayed on the screen. Adjust the waveform to facilitate analysis and judgment of the approximate range of the fault. We can help the locator to accurately locate. Through the left and right indication of the dial pointer, the pulse waveform signal can be identified and the fault point can be accurately found.