Electrical cable

An electrical cable is a group of one or more wires bundled together.

These cables act as conductors to carry electric current. They allow power or signals to move from one device to another. Some cables are used for long-distance communication under the sea. Other cables are used for bulk power transmission using high-voltage. You can also find them in building wiring for lights and power.

Using cables saves labor because all the wires can be installed at once.

To make a cable work well, it needs a specific structure. Each wire has its own insulation to keep the electricity contained. Some cables use stranding to stay flexible. This is a way of working where many small wires are twisted or braided together. This makes the large wire much easier to bend than a solid one.

Copper wires inside might be bare or plated with metals like tin, gold, or silver. Tinning helps prevent oxidation and makes soldering much easier. It can even help with removing rubber insulation.

People have changed how they make cables over a long time. In the 19th and early 20th centuries, makers used cloth, rubber, or paper for insulation. Later, a natural latex called gutta-percha was used for underwater cables. In 1930, the first man-made plastic called polyethylene was invented. It was not used outside the military until after World War 2. During that war, a telegraph cable using polyethylene was laid across the English Channel. This helped support troops following D-Day.

Cables can sometimes pick up or send out unwanted energy. This is called an electromagnetic field. This can cause noise that messes up a signal.

To stop this, engineers use three main design techniques. One is shielding, which uses a layer of foil or wire mesh to act like a Faraday cage. Another is coaxial geometry, where the inner wire sits exactly in the center of a circular shield. The third is a twisted pair, where two wires are wound around each other to cancel out interference.

Safety is a very important part of how cables are made. Most cable jackets are made of plastic that can burn.

Because of this, grouped cables can be a fire hazard. To stay safe, makers can use fire retardant coatings on the outside of the cable. They can also put cables inside boxes made of noncombustible materials. This helps to isolate the threat and stop fire from spreading. Different types of cables exist for different jobs, like ribbon cables for many wires or armored cables for extra strength.