Search results
Results from the WOW.Com Content Network
Level crossing signals are electronic warning devices for road vehicles at railroad level crossings. Level crossings can be operated in various ways. In some countries such as the UK, the warning devices are more often than not activated by remote control, I.e. an operator pressing buttons. However, the majority of countries have automated systems.
A level crossing is an intersection where a railway line crosses a road, path, or (in rare situations) airport runway, at the same level, [1] as opposed to the railway line or the road etc. crossing over or under using an overpass or tunnel.
Some level crossings that are located close to intersections with traffic lights program the signals with a preemption sequence so when the approaching train trips the track circuit, it not only activates the crossing signals, but also changes the traffic lights facing the crossing to green, to clear any traffic that may be queued on the ...
Certain types of road level crossings; Level junctions and gauntlet track; A signal cannot display a 'proceed' aspect unless the infrastructure item(s) that it protects are in the correct position for the passage of a train or, in the case of flat junctions and gauntlet track, no other signal is cleared for a conflicting move.
A signal used in the Delhi metro, typical of urban light rail signals. Usually, signals and other equipment (such as track circuits and level crossing equipment), are powered from a low voltage supply. The specific voltage varies with the country and equipment used.
Bracket masts tend to be the tallest type of signal to allow the train crew to see the signal over a train on the intervening track. Signals in electrified territory may be mounted on the catenary structure, and signals on bi-directional lines may be mounted back-to-back on the same mounting device. Prior to 1985, signals were required by ...
The 15-second clip shows the train approaching a level crossing at speed when a man wearing a cap is seen rushing across from one side of the line to the other.
An electro-mechanical treadle. In railway signalling, a treadle is a mechanical or electrical device that detects that a train wheel has passed a particular location. They are used where a track circuit requires reinforcing with additional information about a train's location, such as around an automatic level crossing, or in an annunciator circuit, which sounds a warning that a train has ...