Concept
Overhead power line
Related concepts (23)
Electrical cable
An electrical cable is an assembly of one or more wires running side by side or bundled, which is used to carry electric current. One or more electrical cables and their corresponding connectors may be formed into a cable assembly, which is not necessarily suitable for connecting two devices but can be a partial product (e.g. to be soldered onto a printed circuit board with a connector mounted to the housing). Cable assemblies can also take the form of a cable tree or cable harness, used to connect many terminals together.
Electrical conductor
In physics and electrical engineering, a conductor is an object or type of material that allows the flow of charge (electric current) in one or more directions. Materials made of metal are common electrical conductors. The flow of negatively charged electrons generates electric current, positively charged holes, and positive or negative ions in some cases. In order for current to flow within a closed electrical circuit, one charged particle does not to travel from the component producing the current (the current source) to those consuming it (the loads).
Overhead line
An overhead line or overhead wire is an electrical cable that is used to transmit electrical energy to electric locomotives, trolleybuses or trams. The generic term used by the International Union of Railways for the technology is overhead line. It is known variously as overhead catenary, overhead contact line (OCL), overhead contact system (OCS), overhead equipment (OHE), overhead line equipment (OLE or OHLE), overhead lines (OHL), overhead wiring (OHW), traction wire, and trolley wire.
Undergrounding
In civil engineering, undergrounding is the replacement of overhead cables providing electrical power or telecommunications, with underground cables. It helps in wildfire prevention and in making the power lines less susceptible to outages during high winds, thunderstorms or heavy snow or ice storms. An added benefit of undergrounding is the aesthetic quality of the landscape without the powerlines. Undergrounding can increase the capital cost of electric power transmission and distribution but may decrease operating costs over the lifetime of the cables.
Overhead cable
An overhead cable is a cable for the transmission of information, laid on utility poles. Overhead telephone and cable TV lines are common in North America. These poles sometimes carry overhead power lines for the supply of electric power. Power supply companies may also use them for an in-house communication network. Sometimes these cables are integrated in the ground or power conductor. Otherwise an additional line is strung on the masts. Cables are arranged on poles with the most dangerous cables, that is, those carrying power, strung highest.
Lineworker
A lineworker (or powerline worker) constructs and maintains the electric transmission and distribution facilities that deliver electrical energy to industrial, commercial, and residential establishments. A lineworker installs, services, and emergency repairs electrical lines in the case of lightning, wind, ice storm, or ground disruptions. Whereas lineworkers generally work at outdoor installations, those who install and maintain electrical wiring inside buildings are electricians.
Power-line communication
Power-line communication (also known as power-line carrier), abbreviated as PLC, carries data on a conductor that is also used simultaneously for AC electric power transmission or electric power distribution to consumers. A wide range of power-line communication technologies are needed for different applications, ranging from home automation to Internet access which is often called broadband over power lines (BPL).
Optical ground wire
An optical ground wire (also known as an OPGW or, in the IEEE standard, an optical fiber composite overhead ground wire) is a type of cable that is used in overhead power lines. Such cable combines the functions of grounding and communications. An OPGW cable contains a tubular structure with one or more optical fibers in it, surrounded by layers of steel and aluminum wire. The OPGW cable is run between the tops of high-voltage electricity pylons.
Electrical injury
Electrical injury is a physiological reaction caused by electric current passing through the body. The injury depends on the density of the current, tissue resistance and duration of contact. Very small currents may be imperceptible or produce a light tingling sensation. A shock caused by low and otherwise harmless current could startle an individual and cause injury due to jerking away or falling. Stronger currents may cause some degree of discomfort or pain, while more intense currents may induce involuntary muscle contractions, preventing the person from breaking free of the source of electricity.
Polyphase system
A polyphase system is a means of distributing alternating-current (AC) electrical power where the power transfer is constant during each electrical cycle. AC phase refers to the phase offset value (in degrees) between AC in multiple conducting wires; phases may also refer to the corresponding terminals and conductors, as in color codes. Polyphase systems have three or more energized electrical conductors carrying alternating currents with a defined phase between the voltage waves in each conductor; for three-phase voltage, the phase angle is 120° or 2π/3 radians (although early systems used 4 wire two-phase).