A railroad switch moves tracks at railway junctions, allowing trains to turn left or right. Switch heaters are installed on the switches to heat the rail and prevent snow and ice build-up from freezing the switches. These heaters can be powered by natural gas, propane or electricity. Years ago, railroad employees had to manually clear the snow off of switches and use gas torches to melt any ice that had built up.
GPS, or "Global Positioning System," is a navigation system that uses satellites to track the time and location of anyone who has a GPS Receiver. Rail systems use GPS systems to track the movement of all locomotives. By tracking all locomotives, they know when to re-route a train to avoid a collision or derailment.
Bearing temperature scanners take the temperature of each wheel bearing as it passes by the scanner. If one or more of the bearings show elevated temperatures, or are overheating, an alarm goes off. If an alarm is sent, the train is stopped until the defect is corrected or the problem car is removed. The data is also used to keep track of trends or problem areas over several locations, helping to predict future derailments.
Loose wheels or broken flanges on the wheels of a train car can cause the cars to run off the track, or derail. A loose-wheel, broken-flange detector has a row of 124 electromechanical fingers on a rail. The outer flange of a normal wheel pushes down on the bottom finger while a broken wheel flange will not. If a broken-flange is detected, an alarm goes off. These fingers, or sensors, can also detect bent axles and wheels that are mounted incorrectly.
