A utility pole, telegraph pole, telephone pole, power (electricity) pole, or telegraph post is a pole used to support overhead electrical wires, cables, and optical fiber and associated equipment. They may carry both wires to distribute electric power for an electric utility, and communication cables for telecommunications networks. Electric power wires are routed overhead as a cheap way to keep them insulated from the ground, and out of contact with the public. Utility poles were first used in the mid-1800s with telegraph systems. They are used for lower voltage power distribution; higher voltage power transmission lines are suspended from metal towers called pylons.
The appearance of telecommunication poles has changed with technology through the 20th century, with for example the loss of the stereotypical but now redundant crossbeam used to mount rows of insulators for open wire telephone circuits. These more traditional poles can sometimes be seen unaltered beside non-electrified railways, or where no effort has been made to remove crossbeams not in use.
However in the countries of Eastern Europe, in Russia and in countries of the third world, there are still many utility poles carrying bare wires mounted on insulators not only along railway lines, but also along roads and sometimes even in urban areas. Errant traffic being uncommon on railways, their poles are usually less tall.
In the UK, much of the rural electricity distribution system is carried on wood poles. These normally carry electricity at 11 or 33kV (three phases) from 132kV substations supplied from super pylons to distribution substations or pole mounted transformers. The conductors on these are bare metal connected to the posts by insulators. Wood poles can also be used for LV distribution to customers.
Today utility poles may hold much more than the uninsulated thin copper wire that they originally supported. Thicker cables holding many twisted pair lines or coaxial cable or even fibre-optics may be carried. Simple analogue repeaters or other outside plant equipment have long been mounted against poles, and often new digital equipment for multiplexing/demultiplexing or digital repeaters may now be seen. In many places, as seen in the illustration, providers of electricity, television, telephone, street lighting, traffic signals and other services share poles, either in joint ownership or by renting space to each other. Such poles provide a safe gap between power lines on top and signal wires below.
British Telecom posts are usually marked with the following information:
The date on the pole is put on by the manufacturer and refers to the date the pole was "preserved" (treated to withstand the elements usually by using creosote).
In other especially rural areas, even their simple sequential numbering still excels the local house numbering system in providing a means of communicating location information: "Turn left at Williams Main Line #43. My house is at pole #43-Left-7."
Laminated crossarms made from decommissioned chromated copper arsenate-treated utility pole wood. Part II: preservative retention, glue-line shear, and delamination.
Nov 01, 2010; Abstract Laminated utility pole crossarms constitute one of the potential industrial products that can be produced from...
US Patent Issued to Daewoo Electric on Oct. 19 for "Method for Replacing Concrete Utility Pole Without Interrupting Power Supply by Adopting Pole Clamp and Pole Crusher" (South Korean Inventor)
Oct 20, 2010; ALEXANDRIA, Va., Oct. 23 -- United States Patent no. 7,814,725, issued on Oct. 19, was assigned to Daewoo Electric Co. Ltd....
Laminated crossarms made from decommissioned chromated copper arsenate-treated utility pole wood. Part I: mechanical and acoustic properties.
Feb 01, 2010; Abstract In recent years, rising concern over the disposal of preservative treated wood has generated interest in the reuse and...