A fire in the control centre of the pivotal Itarsi Railway Junction in UP has caused one of the largest and lengthiest ­ train disruptions in over a decade, with more than 70 trains being cancelled each day for the last 22 days; over 3,000 in all, resulting in 50,000 ticket refunds a day. And given the extent of damage to the Route Relay Interlocking (RRI) panel ­ the nerve centre of a station that routes all major rail traffic between the four cardinal directions ­ railway officials estimate that services will be restored only by July 23.Monetary loss caused by the dysfunctional system is in the region of Rs 1,200 crore, sources in the railways said.At least 900 trains originating from and headed for Mumbai have been cancelled since the fire broke out.A fire that broke out at 5.45 am on June 17 destroyed the central cabin of the route relay interlocking system at Itarsi in Madhya Pradesh, resulting in a cascading effect on the country's entire rail network, slowing down train movement, and forcing operators to resort to manual signalling methods, including flags and “authority to proceed“ chits handed to drivers approaching switching points.“The electronic dashboard controls train movement over significant sections. The entire panel, connected with the signal points and track turnouts, has been gutted. It is a huge system with thousands of cables and circuits and railway engineers have to completely set up a new system. It is taking time because of the complexity of the job,“ a senior railways official said. “It's critical to understand that it is very dangerous to allow the same volume of train movement without the RRI system in place.“ Itarsi Junction normally handles 300 trains a day. The burned down panel has whittled that number down to a third of that number.According to railway employees, the RRI cabin was ill-maintained and did not house a smoke detector. “This disaster could have been averted,“ an official told Mumbai Mirror. No offi cial explanation was forthcoming.The task at hand is daunting. In all, close to 120 km of cables must be replaced; over 300 km of jumper cables installed; 3 lakh segments to be soldered and joined with precision; and each one of the 900 relays in the control room must be set right. “We have deployed more than 950 engineers and over 50 officers to work on the site day and night,“ Piyush Mathur, chief spokesperson, West Central Railway, said.Former railway board member (mechanical) Subodh Jain said that a crisis of this scale hasn't occurred in over a decade. “There was an arch bridge collapse on Western Railway between Surat and Mumbai in 2003; trains had been diverted and cancelled for nearly 20 days, but not on this scale. This is a rare crisis,“ he said.In Mumbai, travellers with reserved tickets have had to spend nights at CST, waiting for services to resume or find alternative routes home. Some made tortuous journeys back to the city.“I was to travel back [to Mumbai] from Char-dham Yatra with my friends. We had a booking on the Varanasi-Mumbai Express. But as we reached the station, we were told that the train had been cancelled. We were helpless and tried booking a ticket in another train but they were all full.We had to board a general coach which was jam packed. We stood on the train for the entire overnight journey from Varanasi to Itarsi,“ said Malan Palekar, 58.Railways officials said the figure of 50,000 ticket cancellations and refunds from online tickets across the country is just the tip of an iceberg, because more refunds have been given through booking counters.Asked how many passengers have been affected, railways officials said they do not have a mechanism to keep track, but the figure could run into lakhs.In fact, just one zone, the south east central railway, has released its figures of losses that have reached Rs 2.5 crore till June 29. While 5,260 tickets were cancelled in Raipur zone with railways bearing a loss of Rs 35,23,135, Nagpur zone saw 25,790 ticket cancellations with a refund of Rs 1,07,18,675. Bilaspur zone had to refund Rs 1,15,13,245 for cancellation of 23,475 tickets. These are just reserved ticket passengers. “Other zones are yet to calculate the exact losses, but the estimate is of Rs 1,200 crore already,“ an official added.BK Mishra from Amethi, who runs a taxi for a living in Mumbai, could not make it in time for his father's surgery. “I had to go as my father was unwell. He is well now, but I should have been there. I had booked tickets a month in advance,“ he said.Vivek Mishra, a teacher by profession working in Mumbai, is stuck in Sultanpur. “My train got cancelled thrice, Saket Express and Udyog Nagri. I need to return to Mumbai, but I have been stuck here. Now I am figuring out how to come back,“ he said.Route Relay Interlocking (RRI) is the dashboard used in large and busy stations that are required to handle high volumes of train movements.The RRI controls the entire route traced by a train as it passes through a station. All associated points and signals along the track can be set at once by a switch for receiving, holding, blocking, or dispatching trains.The system mirrors the actual geographical layout of signal switches and push buttons. All that an operator is required to do to effect a switch in the route is determine where a train is and to which line it must be shifted. The RRI takes care of the rest.When a route is set and locked, the route is illuminated by white strip lights in the track circuit configurations throughout the route (except the overlap).Itarsi's RRI central cabin controls hundreds of points and signals. It pilots traffic moving in the direction of Gorakhpur, Lucknow, Kanpur, Patna, Mumbai, Nagpur, Allahabad and Jabalpur.When Itarsi's system burned down on June 17, it was akin to an Air Traffic Control tower losing its flight sequencing system; train operators had to resort to antiquated manual signalling techniques.