Video explanation: How the Kavach automatic train protection system works


oi-Vicky Nanjappa


Posted: Saturday March 5th 2022, 11:04 AM [IST]

Google One India News

New Delhi, March 5: This technology is revolutionary in a country where a large population depends on the railways. However, in an effort to put an end to railway accidents, a locally developed automatic train protection system, known as Kavach (shield), was developed.

Video explanation: How the Kavach automatic train protection system works

The system has been designed to ensure that there are no accidents. Moreover, it is the cheapest automatic train protection system in the world. The trial run of the system was conducted in Secunderabad with Railways Minister Ashwini Vaishnaw aboard one of the trains. The Chairman of the Board of Railways was also on the train with him.

During the test, the two trains using the system stopped 380 meters apart.

“Rear-end crash tests passed. Kavach automatically stopped the locomotive before 380m from another locomotive ahead,” Vaishnaw said.

Kavach controls the speed of the train through an automatic breaks app. This is useful when the locomotive driver fails to apply breaks. Kavach has been approved for a speed of 160 kilometers based on trials.

Trains will also stop on their own when the digital system notices a manual error such as a red signal “jump” or any other malfunction, senior officials said.

Once implemented, it will cost Rs 50 lakh per kilometer to operate, compared to around Rs 2 crore globally, they said.

A signal is passed in case of danger (SPAD) when a train passes a stop signal when it is not authorized to do so.

‘Kavach’ controls the speed of the train by automatic application of the brakes in case the locomotive driver does not.

“It operates on the principle of continuously updating movement using high frequency radio communication. It also complies with SIL-4 (Safety Integrity Level – 4) which is the highest level of safety certification.

“RFID tags are provided on the tracks and in the yard for each track and signals for track identification, train location and train direction identification. The “on-board display Signal Aspect Tester (OBDSA) is to help locomotive drivers check signals on on-board consoles even when visibility is poor,” an official said.

Additionally, once the system is activated, all trains within a 5 km radius will stop to provide protection for trains on adjacent tracks.

Currently, loco pilots or assistant loco pilots typically stick their necks out the window to watch for warning signs and signals, officials said.

It also includes fixed equipment to collect signal inputs and locomotive inputs and relay them to a central system for seamless communication with the train crew and stations.

The first field trials on passenger trains began in February 2016 and based on the experience gained, the initial specifications of the Kavach were finalized in May 2017.

Subsequently, the independent safety assessment of the system by a third party (Independent Safety Assessor. ISA) was conducted and based on the development project and the ISA safety assessment, three companies were approved by the railway’s RDSO (Research Design and Standards Organisation) in 2018-19 to work up to a train speed of 110 km/h.

Subsequently, based on further tests, Kavach was approved for speeds of up to 160 km/h. The railways are trying to find more suppliers of this technology.

Announced in the union’s 2022 budget under the Atmanirbhar Bharat initiative, 2,000 km of railway network is expected to be integrated with world-class indigenous ‘Kavach’ technology, for safety and increased capacity in 2022 -23.

So far, Kavach has been deployed on over 1,098 km of route and 65 locomotives in South Central Railway’s ongoing projects.

In addition, Kavach is expected to be implemented on the Delhi-Mumbai and Delhi Howrah corridors, having a total kilometer of about 3000 km, under the “Mission Raftar project for speed increase to 160 km/h. Tenders for this work have been launched,” the officials said.

(With PTI inputs)

Article first published: Saturday, March 5, 2022, 11:04 a.m. [IST]