Four-quadrant gate

From Wikipedia, the free encyclopedia

A level crossing with four-quadrant gates at Chertsey, England. The gates are rising.

A four-quadrant gate is a type of boom barrier gate protecting a grade crossing. It has a gate mechanism on both sides of the tracks for both directions of automotive traffic. The exit gates blocking the road leading away from the tracks in this application are equipped with a delay, and begin their descent to their horizontal position several seconds after the entrance gates do, so as to avoid trapping highway vehicles on the crossing. Four-quadrant gates are safer than two-quadrant gates, because they prevent drivers from illegally driving their vehicles around lowered gates to try to beat a train.

In the UK, such crossings are categorised as 'Manually Controlled Barriers' (MCB) because they are always manually controlled, usually from a signal box. Some are known as MCB-CCTV level crossings, because they are supervised by video link to the signal box from which they are remotely controlled.

[edit] See also

• Toll collection technology

[edit] External links

• Picture of four-quadrant gate

This rail-related article is a stub. You can help Wikipedia by expanding it.

This road-related article is a stub. You can help Wikipedia by expanding it.