Conductors, insulation, and a protective jacket are the three main components of a cable. The composition of each cables changes depending on the use. Coaxial cables have an outer protective coating to shield against electromagnetic interference (EMI) and radio frequency (RF) radiation. Sheath-covered cables are used in power distribution systems and other applications where they need to be able to withstand mechanical stress without breaking. Unsheathed cables are used where there is little or no chance of them being exposed to physical damage.
Cables are made up of multiple strands which are held together by various methods. A single conductor cable consists of a single strand of metal or polymeric material that carries electrical signals. The term "conductor" when used in connection with cables refers to the actual element of the cable that conducts electricity, not any covering or shielding that may be applied to it. Other types of conductors include solid wire, stranded wire, fiber optic cable, and tape. Each type has its own advantages and disadvantages which will vary depending on the application for which you are using it.
Insulation surrounds and protects the conductor within the cable. It provides separation between the different wires/cables inside the sheath or casing and prevents them from coming into contact with one another. There are two types of insulation: organic and inorganic.
Cables are categorised into five categories based on their use, as follows:
An electrical cable is made up of a conductor, which directs the electrical flow, and insulation, which keeps the electrical flow contained inside the conductor. They can also include additional auxiliary features that ensure their lifetime. The conductor can be either metal or non-metal (such as fiber optic), while the insulation can be either natural or synthetic.
Non-conductive materials, such as plastic or rubber, are used in various forms of wiring to create barriers between wires or groups of wires. These materials can be used alone or in combination with other types of insulation. For example, plastic tape is commonly used to insulate power cables; it provides flexibility while keeping the overall diameter small.
Conductors are usually made from copper, but other metals can be used instead. The amount of current that a conductor can carry is related to its size and shape. The larger the cross-section of the conductor, the more current it can carry. A round conductor carries more current than an angular one of the same size. The number of conductors in a cable is called its load capacity. Cables are designed with enough conductors to meet the expected maximum load for a given application. Larger loads will require more conductors. Conductors are grouped together by material type (i.e., metal wires inside a tube) or purpose (i.e., multiple strands of wire inside a single jacket).
Electrical cables function by allowing current to flow along a low-resistance route. Electrical cables are made up of a core of metal wire with strong conductivity, such as copper or aluminum, as well as various material layers such as insulation, tapes, screens, mechanical armouring, and sheathing. The term "cable" also includes fiber-optic cables and coaxial cables.
The three main types of electrical cable are solid wire, stranded wire, and fiber-optic cable. Each type has its advantages and disadvantages which are discussed further in this article.
Solid wire is made from one single length of conductor. It is used for static applications where the weight of the cable is not important, such as fence lines or power cords. The advantage of solid wire is that it has no shielding unless specifically included in the design. This makes it easy to insert equipment into the wall cavity without having to worry about noise interference from other devices on other cables.
Stranded wire is made by twisting several lengths of conductor together. The number of twists determines how many times the conductor will be around the central core. This gives rise to different terms such as monowire (single), dinewire (double), tripplewire (triple). The advantage of stranded wire is that it has more capacity for conducting electricity than solid wire of the same size, so it can carry more weight before it becomes overloaded.