The 4X120, 4X150, 4X185 fireproof security power cable is a 4-core power transmission cable specially designed for key equipment such as generators. With aluminum conductors and XLPE insulation as the core, it has both excellent fireproof performance and stable electrical transmission capacity, playing an irreplaceable role in emergency power supply, industrial guarantee and other scenarios.​ The conductor is made of high-purity aluminum material with a purity of ≥99.7%, manufactured through multi-strand compacted stranding process, which not only ensures good conductivity, but also improves the flexibility of the cable. The DC resistance of single-core conductors of the three specifications at 20℃ is respectively: 4X120mm² ≤0.158Ω/km, 4X150mm² ≤0.124Ω/km, 4X185mm² ≤0.0991Ω/km, all lower than the industry standard, which can effectively reduce energy loss during power transmission. The weight of aluminum conductor is only 1/3 of that of copper conductor of the same specification, which greatly reduces the installation and transportation burden, and is especially suitable for wiring in space-constrained areas such as generator rooms.​ The insulation layer is made of flame-retardant XLPE (cross-linked polyethylene) material. After special fireproof treatment, its temperature resistance level reaches 90℃, and it can withstand a high temperature of 250℃ during short circuit (within 5 seconds). It has passed the GB/T 19666-2019 fireproof test, and can maintain circuit integrity within 3 hours of direct burning by 800℃ flame, ensuring that the generator can continue to supply power in extreme situations such as fire. The volume resistivity of XLPE insulation is ≥10¹⁴Ω·cm, and the dielectric loss tangent is ≤0.002 (at 90℃), with excellent insulation performance, which can effectively isolate the risk of electric leakage and ensure the safety of power transmission.​ The overall structure design of the cable strengthens fire resistance and mechanical performance: the inner sheath is made of low-smoke halogen-free flame-retardant polyolefin material, with an oxygen index of ≥32%. When burning, the smoke density is low (light transmittance ≥60%) and no toxic gas is released; the outer armoring is double-layer galvanized steel tape, and the armoring thickness increases with specifications (0.3mm for 120mm² and 0.5mm for 185mm²), with a tensile strength of ≥300MPa, which can withstand vibration impact and external mechanical extrusion during generator operation. In addition, the cable is also equipped with a semi-conductive shielding layer, which can evenly distribute the electric field and avoid insulation aging caused by partial discharge.​ The current-carrying capacity is adapted to the generator power demand: the 4X120mm² cable has a current-carrying capacity of about 240A when laid in air, suitable for 50-100kW small and medium-sized generators; the 4X150mm² has a current-carrying capacity of about 290A, matching 100-150kW generators; the 4X185mm² has a current-carrying capacity of 350A, which can be connected to 150-200kW large generators. Its minimum bending radius is 12 times the cable outer diameter (static). The outer diameter of 120mm² cable is about 65mm, and the static bending radius is 780mm, which is convenient for flexible laying in complex pipelines around the generator.​ In practical applications, this cable is mainly used for the connection between generators and distribution panels, emergency busbars, and is widely used in hospitals, data centers, high-rise buildings and other places with high requirements for power supply reliability. In case of emergencies such as fire, its fireproof characteristics can ensure that the generator continues to supply power to key equipment such as fire pumps, emergency lighting and elevators, buying time for personnel evacuation and disaster control. At the same time, the low-smoke and halogen-free characteristics reduce secondary injuries in fires, meeting the strict requirements of modern safety specifications for cables.​ Overall, through material innovation and structural optimization, the 4X120, 4X150, 4X185 fireproof security power cable has achieved an efficient balance between fire safety, electrical performance and installation convenience, providing reliable power transmission guarantee for generator systems.