Diagnosis Of The Nature Of Cable Faults

The nature of the diagnostic cable fault is to determine whether the fault resistance is high impedance or low resistance; is it a flashover or a closed fault; is grounding, short circuit, disconnection, or a mixture of them; is single phase, two phase, or three Phase failure. The nature of the fault can be initially determined based on the phenomenon that occurs when the fault occurs.

For example, when a running cable fails, if only a ground signal is given, there may be a single-phase ground fault. When the relay protection overcurrent relay operates and a trip occurs, a two-phase or three-phase short-circuit or ground fault of the cable may occur, or a short-circuit and ground-mixing fault may occur. In the event of these faults, a short circuit or ground current blows the cable and a wire breakage fault will occur. However, the nature of the fault cannot be completely determined by the above judgment. Several are larger than the nominal cross section. In the actual production process, as long as the DC resistance of the conductor can meet the specified requirements, it can be said that the cross section of the cable is up to standard.