National standard power cables refer to power connection cables designed and manufactured strictly in accordance with China's national electrical standards. They are the core carrier for safe transmission of electrical energy between various types of electrical equipment and power supply networks, and are widely used in civil appliances, industrial equipment, office appliances, building wiring and other scenarios. Their electrical performance, structural dimensions, and safety indicators are all constrained by national mandatory standards, and are the basic guarantee for electrical safety. This type of power cord must comply with corresponding national standards such as GB/T 5023 "Polyvinyl chloride insulated cables with rated voltage of 450/750V and below", GB/T 5013 "Rubber insulated cables with rated voltage of 450/750V and below", GB 2099 "plugs and sockets for household and similar purposes", and pass the mandatory 3C certification of the country. There are clear parameter specifications for conductor material, insulation thickness, sheath performance, plug size, and current carrying capacity to eliminate non-standard hazards. From an internal structure perspective, a standard power cord consists of a conductor, insulation layer, sheath layer, and grounding core wire. The conductor is made of high-purity oxygen free copper material, with a multi strand twisted structure that balances conductivity and bending toughness. The resistance value is stable and meets the standard, and it is not easy to generate heat after long-term use; The insulation and outer sheath are mostly made of environment-friendly polyvinyl chloride (PVC), rubber and other materials, with uniform thickness, high insulation strength, good wear resistance, acid and alkali resistance, and aging resistance, which can effectively isolate the leakage risk. For different usage environments, special formula sheaths such as flame retardant, high temperature resistant, cold resistant, and oil resistant can also be selected to adapt to complex working conditions. According to the core wire structure, there are commonly two core, three core, and multi-core specifications: two core wires are suitable for small electrical appliances with double insulation; The three core wire is equipped with an independent grounding core wire, which is a standard configuration for metal shell electrical appliances and high-power equipment, and can prevent the risk of shell electrification; Multi core wires are used for complex equipment that combines signal and power transmission. The rated voltage covers multiple levels such as 300/300V, 300/500V, 450/750V, etc. The wire diameter strictly corresponds to the current carrying capacity, and can be matched with electrical equipment of different powers. Qualified national standard power cords have clear appearance markings, with 3C certification marks, model specifications, rated voltage, and execution standard numbers printed on the surface. The wire body is flat and smooth, without damage or cracking, with moderate plug insertion and extraction force and stable copper conductivity. It can operate stably for a long time under normal rated conditions, effectively resist the effects of daily bending, pulling, temperature changes, etc. It is a basic accessory to ensure electrical safety and reduce electrical fire hazards, and is also an essential supporting component for various electrical products to be listed in compliance.