Electrical wires are conductors that transmit electrical energy. They are classified as bare wires, magnetized wires, and insulated wires. Bare wires have no insulation layer and include copper and aluminum flat wires, overhead stranded wires, and various profiles (such as shaped wires, busbars, copper busbars, aluminum busbars, etc.). They are mainly used in outdoor overhead lines and indoor busbars and switch boxes.
Why does a conductor generate a magnetic field when energized?
Magnetic wires are insulated conductors that generate a magnetic field when energized or induce a current in a magnetic field. They are mainly used in motor and transformer windings and other related electromagnetic equipment. Their conductor is primarily copper wire, requiring a thin insulation layer and good electromechanical properties, as well as heat resistance, moisture resistance, and solvent resistance. Different insulation materials result in different properties.
Magnetic wires mainly come in two types: enameled wire and wrapped wire. Enameled wire is made by coating bare copper wire with insulating varnish. It has a thinner insulation layer, occupies less space, and is widely used in various motors, electrical appliances, and instruments.
The performance of enameled wire varies depending on the properties of the insulation material used. Wrapped wires mainly include yarn-covered wire, silk-covered wire, glass fiber-covered wire, paper-covered wire, and plastic film-covered wire. Among them, yarn-covered wire and silk-covered wire may be phased out due to their poor temperature resistance and large volume. Glass fiber-covered wire is made by wrapping glass fibers around round copper wire and impregnating it with silicone resin. It can withstand high temperatures of 180℃ and has good insulation performance and mechanical strength. Paper-covered wire is mainly used in oil-immersed transformers. Plastic film-covered wire is made by coating a polyimide film with a certain adhesive and wrapping it around the conductor and then baking it. Its insulation layer is tough and elastic, easy to wind, and wear-resistant and heat-resistant, and is widely used in aerospace equipment.
Insulated wires generally consist of a conductive core, an insulation layer, and a protective layer. The core can be classified into four types according to usage requirements: Rigid, flexible, mobile, and extra-flexible. Cores also come in single-core, two-core, three-core, and four-core configurations. The insulation layer is generally made of rubber, plastic, etc. These types of insulated wires are widely used in various instruments, telecommunications equipment, power lines, and lighting circuits with AC voltage below 500 volts and DC voltage below 1000 volts.
