Middle breakdown of high voltage cables: Cables rarely break down from the middle. If they break down from the middle, they may be caused by the following reasons:
1, high voltage cable itself quality problems, such as a part of the cable contains bubbles. There is a great difference between the mass constants of bubbles and insulating rubber, so the voltage distribution in these media will be uneven. Most of the applied voltage is concentrated on the bubble with small dielectric constant. When the voltage is increased to air ionization, the dielectric insulation strength is damaged, resulting in breakdown.