Why does the wire short-circuit and catch fire?

According to the statistics of the public security fire department, the accident rate of the entire building caused by the failure of the wires and cables itself accounts for about 40%. In order to ensure that the electrical and electronic operating systems of modern high-rise buildings are unobstructed and increase the safety and reliability of the entire system, we mainly analyze the reasons for short circuits and fires and preventive measures.

 

Major causes of fire in electrical circuits

1. Poor contact. The contact resistance of the line is too large due to a bad wire connector, which causes heat and fire. If the circuit connector is not connected well, it will hinder the flow of electric charge in the wire and generate a lot of heat. When this heat is sufficient to melt the insulation of the wire, the insulation will catch fire and ignite nearby combustibles.

2. The line is overloaded. Wires of a certain material and a certain cross-sectional area have a certain safe ampacity. If the current through the wire exceeds its safe carrying capacity, the wire will heat up. When the temperature of the wire exceeds 250 ° C, the rubber or plastic insulation of the wire will catch fire.

3. Line leakage. Due to the poor insulation performance of the wire insulation or its support material, a small amount of current passes between the wire and the ground. When the leakage is serious, leakage sparks and high temperatures can also be the source of fire.

4.The cable catches fire. The reason why the cable burns is because its protective lead is damaged when the cable is laid; the cable is overloaded for a long time, which reduces or even loses the insulation performance, and the insulation breakdown causes the cable to burn.

 

Measures to prevent fire on electrical wiring

1. Install the electrical wire and as required. Installation of electrical wiring must be in strict accordance with the electrical installation regulations, and a dedicated electrician must be hired to lay the wiring. Electricians must be certified to work.

2. Select the correct electrical wiring. According to the actual needs in work and life, you can choose appropriate specifications of the electrical wiring, and do not use too thin or inferior wires for small and cheap. When selecting wires, pay attention to check whether they are qualified products.

1. Use electrical wiring safely. The installed electrical lines must not be randomly pulled, connected, or added with electrical devices, increasing the power load of the entire line. Pay attention to know the maximum load of the circuit used. Do not exceed this limit during use, otherwise accidents may easily occur.

4. Check electrical wiring frequently. It is necessary to insist on regular inspections, and a specialized electrician is required to help inspect the electrical wiring every time. If the insulation layer is damaged, it shall be repaired in time. The service life of the wire is generally 10 to 20 years. If it is found to be over-aged, it must be replaced in time.

 

Have you learned the causes and precautions of wire fires through this article? If you have any questions about terminal connector, cable connector, electrical wire, electrical cable, etc., please contact us in time.