As mining excavation becomes more mechanized and high-power electrical equipment is introduced, the voltage level of power supply is upgraded, and communication cables for mining are increasingly widely used. Due to reasons such as damp underground conditions, mechanical damage, electrical corrosion of the insulation layer, long-term overloading, bending and twisting fatigue damage, and poor connection techniques, cable failures are frequent. Below is an introduction to specific faults:
Low-resistance grounding or short-circuit fault:
Insulated resistance of a single or multiple cores of a cable to ground, or between cores, is below 10K, with good conductor connections. This can be further categorized into single-phase grounding, two-phase short-circuit or grounding, or three-phase short-circuit or grounding.
2. High-resistance grounding or short-circuit fault:
Cable cores, either single or multiple, exhibit insulation resistance to ground or between cores that is significantly lower than the normal value but higher than 10K ohms. Typically, this involves single-phase grounding, multi-phase short circuits, or grounding issues.
3. *Connection Failure:
The individual cores of the cable are well-insulated, with one or more cores possibly experiencing a break.
4. Continuous Line Faults:
The insulation of each core wire in the cable is good. A single core or multiple cores with a broken or non-broken conductor connected via resistance can be categorized as high impedance wire fault or low impedance wire fault.
5. *Open circuit and grounding fault:
The insulation between the cable cores is good, but the cores are broken, resulting in high or low resistance grounding.
In summary, as a professional or part-time detection personnel, one should believe in the effectiveness of mining cable fault testing instruments. By carefully and calmly analyzing the type and nature of faults, and by accumulating experience and analyzing each detection task in the past, over time, one can master the instruments and equipment with ease, achieving satisfactory results.
