Energy Meter Test Bench is one of our products. Let's share the structure of the power cable.

　　wire construction

　　The wire is mainly composed of conductors and insulators.

　　1. Conductor

　　1.1: Conductor materials: copper, aluminum, iron, silver, gold, optical fiber, etc. Among them, copper is the most widely used, and the power cord is mainly made of soft annealed copper wire. Copper wire is divided into bare copper wire (AS) and tinned copper wire (TS).

　　1.2: Conductor structure: divided into combined conductors and single conductors (the diameter of the conductors has different requirements according to the requirements of each safety regulation).

　　1.3: Conductor resistance: UL/CUL standard: 1m long at 20℃. The standard resistance of soft copper with a cut area of ​​1mm2 is 0.017241Ω.

　　VDE/CCC standard: 1m long at 20°C. The standard resistance of soft copper with a cut area of ​​1mm2 is 0.0195Ω.

　　2. Insulator

　　2.1: Insulator materials: paper, cotton, paint, plastic, rubber, mica, etc. Among them, plastic is the most widely used in electric wires. Plastics are mainly PVC (polyvinyl chloride), PE (polyethylene), PP (polypropylene) and so on.

　　2.2: Insulation resistance: The minimum insulation resistance of the wire insulator specified by UL/CULF is: 20℃, 500VDC, 2.5MΩ/1KFT. VDE/CCC stipulates the minimum resistance of various wire types at 70°C and 80-500VDC.

　　(Insulation resistance is tested differently in UL/CUL and VDE/CCC standards.)

　　2.3: Flame retardancy of insulating materials:

　　2.3.1: UL/CUL is clearly divided into: FT1, FT2, FT4, FT6, VW-1; FT1 or VW-1 is the common requirement of UL for wires, and CUL (CSA) generally only requires the FT2 standard.

　　2.3.2: VDE/CCC and so on also have specific requirements for the resistance combustion of insulating materials, but there is no specific distinction yet.

　　2.4: Insulator withstand voltage: Each safety regulation has different requirements for different wires:

　　UL/CUL is generally divided into: 30, 90, 125, 300, 600, 1000V;

　　VDE/CCC is generally divided into: 300/300V, 300/500V, 470/750V.

　　2.5: Insulator temperature resistance: UL/CUL is generally divided into: 60℃, 75℃, 90℃, 105℃; VDE/CCC is generally divided into: 70℃, 90℃.

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