This 4-core aluminium earth cable is designed for underground power transmission. It uses aluminium conductors and includes 4 cores, one of which can serve as an earth core. The conductor cross-sectional area ranges from 16mm² to 300mm², which can meet power transmission needs of different powers: small cross-sectional areas (16mm²-50mm²) are suitable for small underground distribution branches; medium cross-sectional areas (70mm²-150mm²) can meet the main power transmission of residential areas or factory areas; large cross-sectional areas (185mm²-300mm²) are suitable for large industrial transmission trunks.​ The cable uses XLPE (cross-linked polyethylene) as the insulation layer, which has excellent electrical resistance, aging resistance and mechanical strength, and can resist the impact of underground environments such as humidity and soil corrosion. The outer layer is wrapped with a PVC sheath to further enhance wear resistance and protective performance, making it suitable for long-term underground laying scenarios.​ Its core advantages lie in the lightweight and cost-effectiveness of the aluminium conductor. Combined with the double-layer protection of XLPE and PVC, it balances transmission stability and adaptability to underground environments. It is widely used in underground distribution networks, urban power grid branches and industrial underground transmission projects.

The single-core 2500mm² aluminum conductor cross-linked polyethylene (XLPE)-insulated aerial cable for power transmission is one of the key equipments in the current high-voltage and extra-high-voltage power transmission field. Relying on its excellent electrical conductivity, insulation reliability and environmental adaptability, it plays an irreplaceable role in long-distance and large-capacity power transmission scenarios. The core design of this cable revolves around the three goals of "efficient transmission, safety and stability, and long-term durability", and the selection and technology of each structural component have been accurately optimized to meet the strict requirements of modern power systems for transmission equipment. In terms of conductor structure, the cable adopts a single-core design and a 2500mm² large-section aluminum conductor, which has the dual advantages of "low loss" and "light weight". Compared with traditional copper conductors, aluminum conductors have a lower density (about 1/3 of copper) under the same electrical conductivity, which can significantly reduce the weight of the cable itself, reduce the load-bearing capacity of the towers in the overhead line, and thus lower the overall cost of line construction. It is especially suitable for crossing projects with large spans (such as cross-river and cross-valley lines). At the same time, the large-section design of 2500mm² can effectively reduce the conductor resistance, reduce the Joule heat loss during current transmission, and improve the transmission efficiency. In the transmission lines of 500kV and above voltage levels, the conductor with this section can realize the current-carrying capacity of thousands of amperes in a single circuit, meeting the large-capacity transmission needs such as power transmission from large power stations (such as hydropower stations and wind farms) and interconnection of main power grids between regions, and helping to solve the problem of "uneven spatial and temporal distribution of power supply and demand". In terms of the insulation layer, the cable uses cross-linked polyethylene (XLPE) as the insulation material, which is the core feature that distinguishes it from traditional oil-immersed paper-insulated cables and is also the key to ensuring the long-term safe operation of the cable. After cross-linking, the molecular structure of XLPE material changes from linear to three-dimensional network, which has far better heat resistance, aging resistance and mechanical strength than ordinary polyethylene: its long-term allowable operating temperature can reach 90℃, and the maximum temperature can withstand 250℃ (short-term) in case of short circuit. It can adapt to the temperature changes caused by the load fluctuation of the power system, and avoid the insulation layer from cracking or performance attenuation due to thermal expansion and contraction. At the same time, the XLPE insulation layer has a low dielectric loss tangent value and high volume resistivity, with stable insulation performance, which can effectively suppress partial discharge and reduce the risk of cable failure caused by insulation breakdown. In addition, XLPE material does not contain oil substances, so there is no problem of leakage pollution, which is friendly to the environment such as soil and water sources, and conforms to the current development concept of "green power" construction. From the perspective of application characteristics of aerial laying, the cable also has excellent resistance to environmental interference. To adapt to the aerial scenario, the outer layer of the cable is usually equipped with a weather-resistant sheath (such as polyethylene or polyvinyl chloride sheath) and an anti-corrosion layer, which can resist the erosion of harsh natural environments such as ultraviolet radiation, rain, snow, freezing, acid-base haze, and extend the service life of the cable. Under normal maintenance conditions, its design service life can reach more than 30 years, which significantly reduces the operation and maintenance cost of the line. At the same time, the single-core structure makes it more flexible in the laying process, and the installation method can be adjusted according to the line path. Moreover, there is no need to consider the phase arrangement of multi-core cables, which simplifies the construction process and shortens the project cycle. In practical applications, this cable is widely used in key fields such as national main power grids, new energy grid connection, and urban power grid upgrading. For example, in the extra-high-voltage transmission projects across provinces and regions, it can efficiently transmit the power from large energy bases in the west to the load centers in the east, alleviating the contradiction between regional power supply and demand. In new energy projects such as wind power and photovoltaics, its large current-carrying capacity can adapt to the volatility of new energy power generation, ensuring the stable grid connection of power. In the transformation of urban power grids, compared with traditional overhead conductors, its insulation structure can reduce the safety distance requirement of the line to surrounding buildings, improve the utilization rate of urban land resources, and help build a "compact and efficient" urban power grid system. In conclusion, through structural optimization and material innovation, the single-core 2500mm² aluminum conductor XLPE-insulated aerial cable for power transmission achieves the multiple advantages of "efficient transmission, safety and reliability, economy and environmental protection". It not only meets the needs of modern power systems for large-capacity and long-distance power transmission, but also provides key technical support for the development of new energy and the upgrading and transformation of power grids. It is one of the important equipments to promote the high-quality development of the power industry.