How To Solve Cable Accessory Discharge Faults？

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Power accessories discharge failure is one of the main problems that have plagued the normal power supply sector for many years. Especially in recent years, the number of cable lines has increased and the number of years of operation has become longer, the huge and complex cable network will often occur failures. Cable operation in the occurrence of the cable body, cable accessories, other cable accessories, and other faults significantly increased a lot. Then, how to diagnose the fault in time to solve the problem is very important. Corona charging and discharging of cable accessories are often generated in the terminal head surface layer. The reason key has: the terminal head surface dirty, three cores bifurcation as the spacing is small, core and core middle gap to produce a capacitor, the generation of mineral acid triggered, the surrounding environment wet and cold, etc.

1. If the corona occurs on the surface layer of the outdoor termination and joint. Can be in the finishing, after the corona charging and discharging surface grinding polishing to remove the marks coated with some heat dissipation paste. If it is an epoxy resin head, can use coarse sandpaper or wood file to carry out sanding and polishing after finishing, add some epoxy resin glue between the straight mouth to widen the plane figure.

2. If the indoor termination and joint surface layer when corona occurs. Can be in the finishing surface turbidity, with glass ribbon coated with epoxy resin glue overall wrapped around several layers within the tail line part of the additional winding multi-layer insulation tape, to enhance its surface dielectric strength can.

3. Various packages of cable accessories head corona charging and discharging situation. Can choose the way of equipotential treatment. That is, in each core insulation layer surface wrapped up a section of metal tape, and connected to clear the corona; in addition, can also use the underlying principle of the ground stress cone will be rated insulation layer wrapped into a ground stress cone posture, to improve the electrostatic field throughout.

4. Because of the wet and cold corona, charging and discharging occur. The first should be used to drain the pipe and improve the natural ventilation countermeasures, and then use infrared induction electric bulb or warm air dry wet and cold surface layer.

5. Installation is carried out thoroughly by the specifications to prevent problems caused by the quality of installation. In the process of practical construction, stripping cables and other bottoms are civilian workers to do (even the power supply bureau of most of them). Some even give the entire joint to the civilian workers and only send technical personnel to tutor on the side. This cannot guarantee the quality of cable joints at the bottom.

Conclusion: Strengthen the supervision of power cables and their daily protection. Develop a system of power cable operation and protection handling system. Clear operation protection part and responsibility, the formation of professional skills, handling experienced team responsible for regular inspection protection. Timely discovery of shortcomings affecting the safe operation of the cable. And develop a reasonable deficiency maintenance plan, improve the shortcomings to eliminate the work of hidden dangers.


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