Cable fire accident appraisal

Power system cables are divided into power cables and information transmission cables according to their uses, which are important channels for transmitting energy and information respectively. If the power cable catches fire, it may cause equipment power outage, directly affecting the safe production of the unit, and posing a serious threat to the normal operation of the power plant; if the information transmission cable catches fire, the equipment will lose control. Improper handling can lead to the expansion of the accident, causing interruption of power supply and steam supply to important users, large-scale outage of the steam supply pipeline network, and even personal casualties.
Cable fire accident identification is a professional process that involves a detailed technical analysis of the cable fault and the fire it caused to determine the cause, nature and responsibility of the accident.
In cable fire accident identification cases, Zhongke Testing can provide cable fire accident identification services.

1. There is a problem with the quality of the wire
(1) The quality of the cable itself is too poor, and the ports and intermediate connectors are not manufactured well. The continuous operation of
(2) causes the insulation to age and cause a short circuit and fire.
(3) After long-term overload operation, the fuse cannot cut off the load short-circuit current in time, resulting in overheating of the insulation and a short-circuit fire.
(4) is caused by external mechanical damage.
(5) Oil leakage from oil-filled cables causes fires.
2. External causes
(1) During construction, the slag ignites the cable when electric welding cuts metal.
(2)Fire caused by malfunction of other electrical appliances.
(3) Improper fire prevention measures in the cable tunnel caused the power cable to be soaked in water and cause a fire.
0(4)) Rodents may also cause cable fires.
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GB 43069-2023 Safety technical requirements for mining cables
GB/T 42740-2023 Safety guidelines for wires and cables used in rail transit
GB/T 13029.3-2010 Marine cables Selection and laying of communication cables and radio frequency cables
GB/T 35851-2018 Terminology for aircraft cables and cable harnesses
GB/T 2951.12-2008 General test methods for insulation and sheath materials of electric cables and optical cables Part 12: General test methods—Thermal aging test methods
GB/T 32129-2015 Halogen-free low-smoke flame retardant cable materials for wires and cables
GB/T 2952.2-2008 Cable outer sheath Part 2: Metal sheath cable outer sheath
GB/T 18015-2007 Twisted or star twisted multi-core symmetrical cable for digital communications
GB/T 17737-2018 Coaxial communication cable
YD/T 4304-2023 Single-pair twisted pair cable for digital communications
0XF 306.1-2007 Flame retardant and fire-resistant cable plastic insulation flame retardant and fire-resistant cable classification and requirements
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A fire broke out in a cable in a community. Because it was close to a green belt, the fire spread quickly. Although it was extinguished with the joint efforts of the masses and the fire brigade, it still caused relatively large property losses. As a result, the property management company held the company accountable and entrusted our company to investigate whether the accident was caused by cable quality issues. The
quality analysis expert team tested the cable involved in accordance with national standards and tested the conductor material, insulation resistance, average sheath thickness, outer diameter, conductive resistance and other items, and found that many of the items did not comply with national standards.
But was the fire caused by the low quality of the cable? The quality analysis expert group did not rush to draw a conclusion, but analyzed the environment.
In the end, the quality analysis expert team found that some of the cables had irregularities in buried wires. They had been exposed to the sun and rain for a long time, and the thickness of the sheath itself was not up to standard, which led to wear of the insulation layer, which in turn caused insulation breakdown between the cables or between the lead sheets, resulting in arcs that caused the insulation materials and cable outer protective materials to burn and catch fire.
Therefore, the cable fire accident is not only related to the quality of the cable itself, but also closely related to the damage caused by insufficient wiring standards.