1. According to the different degrees of soft and hard wires, the national standard power cord plugs are mainly divided into the following two categories:
Hard wire (referred to as BV wire), mainly used for daily outdoor power supply, lead wire, erection, etc.;
Soft wire (referred to as BVR wire), mainly used for daily home indoor power supply, lighting, sockets, threading leads, etc.; Hard wire is made of a single copper wire conductor. The flexible wire is a composite conductor made of a plurality of strands of copper wire.
2, the choice of national standard power cord plug wire diameter
Power supply: generally use 6 square BVVB sheathed wire (double core).
Power supply for indoor sockets, kitchen outlets, etc.: 2.5 square (or 1.5 square) BVVB sheathed wires (double core) are generally used.
Lighting power: 1.5 square (or 1 square) BV wire (single core wire) is generally used.
Air conditioning electricity: 4 square (or 6 square) BV wire (single core wire) is generally used.
Water heaters or appliances with voltages above 5000V-7000V: 4 square BVVB sheathed wires are generally used.