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What is a location box?
A location box is located at the point where the trains change tracks. The job of showing the correct route to the railway trains was from here. The signal system is working from this place. The location box plays an important role in the smooth functioning of the interlocking system. Care is taken to ensure that two railway trains do not come face to face on the same track and do not collide with each other through the location box.
Had there been some fault in the railway’s interlocking system, the Coromandel Express would not have received the green signal. This would have prevented a possible accident. But the ‘fail-safe logic’ failed as the railway technicians operated the entire system manually. The accident happened because the failure in the system was not noticed.
The Coromandel Express running on the main line was switched to the loop line due to the interlocking system. A freight train was already standing on this line. Coromandel Express had no stops and its speed was 130 km per hour. At the same speed, she hit a freight train. The severity of the accident was so high that the engine of the Coromandel Express went directly onto the freight train. The Coromandel coaches then derailed and fell onto neighboring tracks. Shalimar Express ran on these tracks in the next few minutes. She hit the Coromandel coaches. After this some coaches of Shalimar Express derailed.