What Is a Cable?
A cable is an electric wire covered with an insulator and a protective coating.
Generally, an electric wire is a bare wire that consist only of conductors that conduct electricity, and an insulated wire that consists of a bare wire covered with an insulator. Cables are composed of one to several insulated wires covered with an outer sheath, providing safety and durability. Copper and aluminum are mainly used as conductors, while polyvinyl chloride and polyethylene are mainly used as insulators.
Types of Cables
Cables come in a wide variety of types, depending on their performance in terms of allowable voltage and current.
1. VCT Cable
VCT stands for Vinyl Cabtyre Cable. It is a cable with vinyl insulation and outer sheath, mainly used for voltages of 600 V AC or less and 750 V DC or less. It has excellent flexibility, water resistance, and heat resistance, making it suitable for mobile cable applications. Cables intended for use at 300 V AC or lower are called VCTF cables.
2. VVF Cable
VVF cables have a simple flat (F) construction with a vinyl (V) sheath covering the outside of the vinyl (V) jacket. VVF cables with a voltage of 600 V or less are widely used for low-voltage indoor wiring, especially for outlets and lighting up to approximately 15 A. VVF cables with a round shape are called VVRF cables. VVR cables with a round shape are also available.
3. EM-EF Cable
An EM-EF cable is a VVF cable in which the insulation and sheath materials are changed from polyvinyl chloride to polyethylene. It is also referred to as an eco-cable. Dioxin and halogen gas emissions during incineration are suppressed, enabling a reduction in environmental load.
4. IV Wire
An insulated wire used for indoor wiring, suitable for electrical equipment of 600 V or less, grounding wires, and crossing wires to power outlets.
5. CV Cable
CV cables have a structure in which the conductor is covered with cross-linked polyethylene and then covered with a vinyl sheath. CV cables are mainly used as power cables. CVD cables consist of two conductors, CVT cables consist of three conductors, and CVQ cables consist of four conductors twisted together.
6. Robot Cables
These cables are specialized for industrial robots. Performance such as bendability and twistability are required. Cables with a variety of superior resistance have been developed to cope with harsh environments.
Applications of Cables
1. Power Cables
Electric power cables are used to transmit electric power. Electric cables used for transmitting electricity from power plants to substations are called transmission cables, while those used to distribute electricity from substations to factories and homes are known as distribution cables. Those used to connect electricity to machinery, lighting, and other equipment are simply called wiring.
2. Cables for Industrial Machinery
These cables are used in home appliances and industrial electrical equipment. They are also used for extension cords, power cords, and wiring between communication devices. High-quality cables are used for their flexibility, heat resistance, flame retardance, water resistance, and safety.
3. Communication Cables
These cables are used for transmitting data and are used in applications such as internet lines. They convert audio, video, and other data into electrical and optical signals, and transmit and receive signals between devices. Fiber-optic cables and coaxial cables are used.