How to determine the fire resistance and durability requirements of Power Connection Cable?

The fire resistance and durability of the Power Connection Cable are key factors in ensuring the safe operation of the system and reducing accidents. When selecting cables, the fire resistance and durability must not only meet the basic legal and regulatory requirements, but also need to be reasonably determined based on the cable use environment, installation method, and extreme conditions that may be encountered. The following is a detailed analysis and key points for consideration of these two aspects:

Fire resistance requirements for cables
The fire resistance of cables is essential to ensure the safety of electrical systems, especially in environments where power equipment is concentrated, people are densely populated, or there is a potential fire hazard. Cables with unqualified fire resistance may become the source of fire spread, which may endanger life safety and the normal operation of equipment in severe cases. The fire resistance of cables generally involves the following aspects:
Flame retardant performance
The insulation material and outer sheath material of flame-retardant cables can effectively slow down the spread of flames in the event of a fire and prevent the fire from spreading to the surrounding environment. According to different flame retardant levels, cables can be divided into the following categories:
Ordinary cables: do not have flame retardant function, and the flame spreads rapidly after the fire source occurs.
Flame retardant cable (FR): Even under the action of fire source, the flame spreads slowly and will automatically extinguish after burning.
Fire resistant cable (FRR): With higher fire resistance, even if a fire occurs, the cable can still maintain its normal operation in a short time, and the power supply will not be interrupted due to the fire.
Fire proof cable (FP): It can maintain insulation performance for a long time in a fire and will not produce harmful gases. It is suitable for high-risk areas.
Fire resistance requirements
Fire resistant cables are required to maintain structural integrity and conductivity for a long time at a certain temperature (usually 950°C or 1000°C). The fire resistance of cables usually depends on their materials and designs. Commonly used fire resistant materials include:
Halogen-free flame retardant (HFFR): Halogen-free cables can not only effectively prevent the spread of flames when a fire occurs, but also will not release toxic gases.

High temperature resistant silicone rubber: Cables used in special high temperature environments have strong high temperature resistance and can maintain normal operation at extreme temperatures.
Low smoke zero halogen requirements
The smoke produced by cables in fires may contain toxic gases, posing a threat to personnel safety. Therefore, low smoke zero halogen (LSZH) cables are often used in buildings, public places, and places that require high safety. This type of cable does not produce toxic gases (such as chlorine, fluorine, etc.) when burning, effectively reducing the harm of fire to personnel health.
Standard certification
The fire resistance of cables should comply with relevant standards and certifications, such as:
IEC 60332: Standard for single and bundled cable combustion tests.
IEC 60331: Cable fire resistance performance standard, which defines the ability of cables to continue to work in fires.
UL 1581: American cable fire resistance and high temperature performance standard.
Cable durability requirements
The durability of cables refers to their stability and reliability in various working environments, especially long-term exposure to harsh conditions. Cables with poor durability are prone to aging, damage or failure, which may lead to safety hazards in the power system. The durability of cables usually depends on the following factors:
Material selection
The durability of cables is closely related to the materials used. Common cable materials include:
Copper/aluminum conductor: Copper has better conductivity but higher cost; aluminum is cheaper and suitable for long-distance transmission.
Insulation layer: Common insulation materials include PVC, PE, XLPE (cross-linked polyethylene), etc., among which XLPE has better anti-aging and heat resistance and is suitable for high temperature environments. PVC insulated cables are usually used in milder environments, but have poor resistance to high temperatures.
Sheath material: The outer sheath material of the cable is commonly PVC, low-smoke halogen-free material or silicone rubber. When selecting, its UV resistance, chemical corrosion resistance, wear resistance and other properties should be considered.
Environmental factors
The durability of cables is also affected by environmental conditions. The temperature, humidity, mechanical stress, chemical corrosion, etc. of the installation environment will affect the long-term service life of the cable:
High temperature environment: In a high temperature environment, the cable insulation layer may age, causing the cable to fail. High temperature resistant materials such as cross-linked polyethylene (XLPE) or silicone rubber should be selected.
Low temperature environment: At low temperatures, some materials (such as PVC) may become brittle and break easily. Choosing low temperature resistant materials (such as cross-linked polyethylene) can help improve the durability of the cable.
Humid environment: An environment with high humidity may cause cable short circuit or insulation damage, so waterproof cables or cables with waterproof coatings should be selected in humid environments.
Chemical corrosion: In environments with strong chemical corrosion (such as chemical plants, oil fields, etc.), chemically resistant cable materials should be selected.
Mechanical strength
The cable may be subjected to mechanical stresses such as stretching, bending, and collision during use. The durability of the cable requires it to have a certain mechanical strength to withstand these stresses without damage. For example, cables reinforced with steel wire can improve their tensile strength and are suitable for places in the external environment that need to withstand large mechanical loads.
UV resistance
For cables used outdoors, their UV resistance is particularly important. When exposed to sunlight for a long time, the cable outer sheath material may be aged by ultraviolet rays, causing it to lose its protective effect. Generally, using sheath materials with UV stabilizers can improve the UV resistance of cables and extend the service life of cables.

The fire resistance and durability requirements of power connection cables should be selected and evaluated according to the specific use environment, construction method, and national and regional safety standards. Ensure that the selected cable can provide long-term stable performance in actual applications and effectively reduce safety risks.