Regarding cables, you need to pay attention to six precautions

Six key precautions that need to be taken for wires and cables in daily life:

(1) Insulation damage causes short circuit faults. The protective lead sheath of power cables is damaged during installation or the insulation of the cables is mechanically damaged during operation, causing insulation breakdown between cable phases or lead sheaths. The resulting arc causes the insulation material and outer protective layer material of the cables to burn and catch fire.

(2) The cable runs under overload for a long time. Long term overload operation causes the operating temperature of cable insulation materials to exceed the allowable temperature for normal heating, resulting in insulation aging and drying of the cable. This phenomenon of insulation aging and drying usually occurs throughout the entire cable line. Due to the aging and drying of cable insulation, the insulation material loses or reduces its insulation and mechanical properties, making it prone to breakdown, ignition, and even multiple simultaneous fires along the entire length of the cable.

(3) Oil immersed cables experience leakage and seepage due to height differences. When the height difference of oil immersed cable laying is large, cable oil leakage may occur. The result of dripping is that the upper part of the cable dries up due to the loss of oil, increasing the thermal resistance of this part of the cable and causing premature breakdown of the paper insulation due to coking. In addition, due to the downward flow of oil from the upper part, space is created at the upper cable head and negative pressure is generated, making it easier for the cable to absorb moisture and causing the end to become damp. The accumulation of oil in the lower part of the cable generates significant static pressure, leading to oil leakage at the cable head. Moisture and oil leakage in cables increase the probability of failure and fire.

(4) Insulation breakdown of the intermediate junction box. The middle joint of the cable joint box oxidizes, heats up, and flows glue during operation due to loose crimping, weak welding, or improper selection of joint materials; When making cable intermediate joints, the quality of the insulation agent injected into the intermediate joint box does not meet the requirements. When injecting insulation agent, there are air holes in the box and the cable box is poorly sealed or damaged, causing moisture to leak in. All of these factors can cause insulation breakdown, form short circuits, and cause cable explosions and fires.

(5) The cable head is burning. Due to the accumulation of moisture and dirt on the surface of the cable head, the ceramic sleeve of the cable head broke, and the distance between the lead wires was too small, causing flashover and ignition, resulting in the burning of the insulation on the surface of the cable head and the insulation of the lead wires.

(6) External sources of fire and heat can cause cable fires. The spread of fires in oil systems, the explosion of oil circuit breakers, the spontaneous combustion of coal powder in boiler pulverizing systems or coal conveying systems, the baking of high-temperature steam pipelines, chemical corrosion caused by acid and alkali, welding sparks, and other sources of fire can all cause cables to ignite.