About Kavach – The Train Collision Avoidance System (TCAS):

• It is India’s very own automatic protection system in development since 2012, under the name Train Collision Avoidance System (TCAS), which got rechristened to Kavach or “armour”.
• It is a set of electronic devices and Radio Frequency Identification devices installed in locomotives, in the signalling system as well the tracks.
• The system talk to each other using ultra high radio frequencies to control the brakes of trains and also alert drivers, all based on the logic programmed into them.
• One of its features is that by continuously refreshing the movement information of a train, it is able to send out triggers when a loco pilot jumps signal, called Signal Passed at Danger (SPAD).
• SPAD is a grave offence in railway operations with respect to safety, and the key to accidents like collision.
• The devices also continuously relay the signals ahead to the locomotive, making it useful for loco pilots in low visibility, especially during dense fog.
• TCAS or Kavach includes the key elements from already existing, and tried and tested systems like the European Train Protection and Warning System, and the indigenous Anti Collison Device.
• It will also carry features of the high-tech European Train Control System Level-2 in future.
• The current form of Kavach adheres to the highest level of safety and reliability standard called Safety Integrity Level 4.