How to Extinguish Fires in Power Cables
How to Extinguish Fires in Power Cables?
Power cables are fundamental materials for transmitting electrical energy and are widely used in economic production. In modern buildings, various wires and cables are becoming increasingly complex, densely packed, and interconnected, providing great convenience. At the same time, cable fire accidents are increasing annually, posing significant risks. If a cable catches fire, what should be done? Next, KINGYEAR Cable will introduce six fire extinguishing methods.
01 Cut Off the Power to the Burning Cable
If a cable catches fire for any reason, immediately cut off its power supply. Then, carefully inspect the cable’s path and characteristics to locate the fault point, and organize personnel to extinguish the fire quickly.
02 Cut Off Power to Non-Faulty Cables in a Cable Trench
When a cable in a trench catches fire, if other cables laid alongside it are at obvious risk of catching fire, cut off their power supply as well. For layered cable arrangements, first cut power to the cables above the burning cable, then to those alongside it, and finally to those below it.
03 Close or Block Both Ends of the Cable Trench
To prevent airflow from intensifying the fire, close the fire isolation door of the cable trench or block both ends, using the suffocation method to extinguish the fire.
04 Ensure Personal Protection During Firefighting
Cable fires produce large amounts of smoke and toxic gases. Firefighters should wear gas masks. To prevent electric shock, rescuers should also wear rubber gloves and insulated boots.
If a high-voltage cable phase is grounded, rescuers must maintain a safe distance: 4 meters indoors and 8 meters outdoors from the fault point to avoid injury from step or contact voltage. These restrictions do not apply when rescuing injured persons, but protective measures must still be taken.
05 Use Appropriate Fire Extinguishing Equipment
Use fire extinguishers such as dry powder, "1211", or carbon dioxide extinguishers. Dry sand or loess can also be used to smother the fire. If water is used, a water spray gun is recommended. For intense fires, after cutting off the power, water can be injected into the cable trench to seal the fault.
06 Avoid Direct Contact with Cable Armor and Manual Movement
During firefighting, never directly touch the cable’s steel armor or attempt to move the cable by hand.
Preventive Measures
To prevent cable fire risks, conduct regular line safety inspections at least once a year. Have professionals thoroughly inspect wires, electrical equipment, and especially long-used connection points. Replace any aged, damaged, or poorly insulated wires promptly to ensure electrical safety.
When purchasing wires and cables, always choose reputable manufacturers, verify quality, and avoid buying non-compliant products simply because they are cheaper.
About Fire-Resistant Cables
Compared to other cables, fire-resistant cables offer superior fire performance. Under high-voltage conditions, they can maintain power supply for several hours and withstand temperatures up to nearly 1,000°C for short periods. Due to their excellent performance, fire-resistant cables can operate at rated voltage intensity.
Key Features:
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Conductors: Made of highly conductive metals with low resistance, reducing energy loss and improving voltage utilization.
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Insulation: Mineral insulation with a high ignition point, ensuring safer operation. Inorganic minerals separate the cable core from the sheath, preventing direct contact.
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Fire Safety: The inorganic materials prevent the cable itself from igniting. Even if exposed to external flames, they produce no toxic gases and can continue operating stably. After a fire, replacement is often unnecessary, making them a truly fireproof solution for ensuring line safety.
Materials and Construction of Fire-Resistant Cables:
Intermediate joints and terminals are critical points for cable stability. Special attention must be paid to their selection and installation.
For cables below 10kV, intermediate joints and terminals share similar structures, focusing on:
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Conductor Connection: Secure connection between the cable core and connecting tube, with low and stable contact resistance.
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Insulation Restoration: Adequate insulation to ensure long-term stable operation, with a safety margin.
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Waterproof Sealing: Effective sealing to prevent moisture ingress.
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Mechanical Protection: The metal shell of the intermediate joint provides both insulation protection and mechanical safeguarding
