Easy Understanding Electrical Cables and Wires

An electrical cable also has different types, color and application as its determining factors. Here’s a brief about cables that you need to understand to determine the correct cable for your home.

Types of Electrical Cables  

There are more than 20 different types of cables available today, designed for applications ranging from transmission to heavy industrial use. Some of the most commonly-used ones include:

Non-Metallic Sheathed Cable  

These cables are also known as non-metallic building wire or NM cables. They feature a flexible plastic jacket with two to four wires (TECK cables are covered with thermoplastic insulation) and a bare wire for grounding. Special varieties of this cable are used for underground or outdoor use, but NM-B and NM-C non-metallic sheathed cables are the most common form of indoor residential cabling.

Underground Feeder Cable 

These cables are quite similar to NM cables, but instead of each wire being individually wrapped in thermoplastic, wires are grouped together and embedded in the flexible material. Available in a variety of gauge sizes, UF cables are often used for outdoor lighting and in-ground applications. Their high water-resistance makes them ideal for damp areas like gardens as well as open-to-air lamps, pumps, etc.

Metallic Sheathed Cable 

Also known as armored or BX cables, metal-sheathed cables are often used to supply mains electricity or for large appliances. They feature three plain stranded copper wires (one wire for the current, one grounding wire and one neutral wire) that are insulated with cross-linked polyethylene, PVC bedding and a black PVC sheathing. BX cables with steel wire sheathing are often used for outdoor applications and high-stress installations.

Multi-Conductor Cable 

This is a cable type that is commonly used in homes, since it is simple to use and well-insulated. Multi-conductor or multi-core (MC) cables feature more than one conductor, each of which is insulated individually. In addition, an outer insulation layer is added for extra security. Different varieties are used in industries, like the audio multicore ‘snake cable’ used in the music industry.

Coaxial Cable

A coaxial (sometimes heliax) cable features a tubular insulating layer that protects an inner conductor which is further surrounded by a tubular conducting shield, and might also feature an outer sheath for extra insulation. Called ‘coaxial’ since the two inner shields share the same geometric axis, these cables are normally used for carrying television signals and connecting video equipment.

Unshielded Twisted Pair Cable 

Like the name suggests, this type consists of two wires that are twisted together. The individual wires are not insulated, which makes this cable perfect for signal transmission and video applications. Since they are more affordable than coaxial or optical fiber cables, UTP cables are often used in telephones, security cameras and data networks. For indoor use, UTP cables with copper wires or solid copper cores are a popular choice, since they are flexible and can be easily bent for in-wall installation.

Ribbon Cable 

Ribbon cables are often used in computers and peripherals, with various conducting wires that run parallel to each other on a flat plane, leading to a visual resemblance to flat ribbons. These cables are quite flexible and can only handle low voltage applications.

Direct-Buried Cable

Also known as DBCs, these cables are specially-designed coaxial or bundled fiber-optic cables, which do not require any added sheathing, insulation or piping before being buried underground. They feature a heavy metal core with many layers of banded metal sheathing, heavy rubber coverings, shock-absorbing gel and waterproof wrapped thread-fortified tape. High tolerance to temperature changes, moisture and other environmental factors makes them a popular choice for transmission or communication requirements.

Twin-Lead Cable 

These are flat two-wire cables that are used for transmission between an antenna and receiver, like TV and radio.

Twinaxial Cable

This is a variant of coaxial cables, which features two inner conductors instead of one and is used for very-short-range high-speed signals.

Paired Cable 

With two individually insulated conductors, this cable is normally used in DC or low-frequency AC applications.

Twisted Pair Cable

The inner insulated wires are twisted or intertwined in twisted pair cable to improve elctromagnetic compatibility. The main purpose of twisted pair cables are to reduce the effect of electro magnetic interference on an electronic signal in nearby communication or data cables.

By twisting two insulated copper wires around each other crosstalk or electromagnetic induction between pairs of wires can reduce.



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