Overhead cable

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In contrast to overhead powerline an overhead cable is a separate cable, usually for the transmission of information, laid on pylons that are sometimes also used for the supply of electric power. Overhead telephone and cable TV lines are common in North America. Elsewhere, overhead cables are laid mainly for telephone connections of remote buildings and temporary mechanisms, as for example building sites.

Also the power supply companies uses them for their in-house telephone network. Sometimes these cables are integrated in the ground or power conductor. Otherwise an additional line is strung on the masts. [1]

When metal-based telephone wire are strung on the same pylons as the power lines, they can pick up noise from the power line. Nowadays fiber optic telephone cable is often used instead, because it can be strung right next to power lines without any interference.

The cables are arranged on the poles so that the most dangerous cables, i.e., those carrying power, are the highest up. The power cables may consist of three separate wires carrying +120V, 0, and -120V AC power. These are distributed to houses and businesses. They can bridge the +120 VAC and -120 VAC to create a 240 VAC circuit, or bridge the +120VAC or -120 VAC and 0 to create 120 VAC circuits.

Overhead cable systems also include a number of different components for managing signaling cables. These include splicing systems that allow multi-conductor cables for distributing telephone signals and snowshoe-shaped devices for reversing the direction of cables.