Cable lines common faults are mechanical damage, insulation damage, moisture insulation, insulation deterioration, over-voltage, cable overheating and so on. When the above line fault occurs, it should cut off the power of the faulty cable to find the point of failure, the fault inspection and analysis, and then repair and test, the excision of excision until the fault is eliminated before resuming power supply.
The most direct cause of cable failure is breakdown of the insulation and breakdown.
a, overload operation. Long-term overload operation, will make the cable temperature, insulation aging, resulting in breakdown insulation, reduce construction quality.
b, the electrical aspects are: cable head construction technology failed to meet the requirements of poor cable head sealing, moisture intrusion into the cable, cable insulation performance decline; failed to take protective measures laid the cable, the protective layer is damaged, reducing insulation.
c, civil construction: poor well drainage pipe ditch, long-term water immersion cable, damage insulation strength; well is too small, the cable bending radius is not enough, long-term by the extrusion of external forces destroyed mainly municipal construction machinery barbaric construction, Digging cut cable.
d, corrosion. Protective layer long-term chemical corrosion or cable corrosion, resulting in failure of protective layer, insulation reduced.