Crossing pylon

From Wikipedia, the free encyclopedia

This article does not cite any references or sources. (June 2007)
Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed.

A crossing pylon is an electricity pylon for a crossing of an overhead line crossing over a body of water, or a valley.

In order to allow ships passing underneath, crossing pylons across wide rivers and sea straits are frequently taller than standard pylons, particularly in areas where the banks of the river or strait are close to the water surface. They are frequently equipped with marking lamps, and unlike standard pylons, often have stairways for easy access to the top.

In many cases they also carry radio antennae and transmitting equipment, especially cell phone towers.

Crossing pylons for valleys, depending on the local topograpy, are not necessarily tall, but the distance between the conducting cables must be sufficient to prevent high winds knocking the conductors into one another. As a result, such pylons have wide crossbars. For very long spans each phase has a separate pylon, particularly if the pylons are short.

Special crossing pylons are often used where aerial tramways cross power lines. These pylons are designed with integral scaffolding so that the tramway cars can be reached without touching a live power line. This enables passengers to be rescued from the tramway if it fails, without cutting the power from the power line. Such installations can be found, for example, south of Zermatt, Switzerland; at the Patscherkofelbahn near Innsbruck, Austria; and at the Penkenbahn in Mayrhofen, Austria.