The cable fault detector can test various types of power cables (voltage level 1kV 35kV), local telephone cables, FM communication cables, coaxial cables and metal overhead lines for short circuit, grounding, high resistance leakage, high resistance flashover fault, cable disconnection, poor contact and other faults. It can also test the length of the cable and the propagation speed of radio waves on the cable. The cable fault detector adopts a variety of fault detection methods, which can accurately determine the precise position of the fault point. It is especially suitable for testing power cables and communication cables of various models and different levels of voltage. The cable detector adopts low-voltage pulse method and high-voltage flashover method to detect various cable faults, especially for cable flashover and high resistance faults, it can be tested directly without burning through. The test of cable fault is based on the principle that the reverse occurs when the line impedance is uneven during the transmission of radio wave in the transmission line.