The following three situations are the reasons for the discharge of explosion-proof switches:

　　One It is the long-term overload operation of the switch that causes the electrical contacts to heat up and the insulation rubber of the switch to age. Due to various reasons such as operation, vibration, or collision, the contact may slide out of the gap between the rubberwood. At this point, a strong discharge occurs between the live wire end and the well grounded metal shell, causing the shell to break through and open flames to burst out, igniting the combustible gas.

　　II The explosion-proof switch itself has quality problems, which means that the insulation performance of the switch is poor and there is leakage.

　　III Corrosive gases may infiltrate the interior of the switch, contaminate the insulation rubber of the switch, accelerate the aging of the rubber, and cause internal discharge of the switch, leading to combustion and explosion accidents.

　　In addition, the investigation also found that the overload protection was lost, which is obviously one of the reasons for the combustion and explosion accident.