Mumbai
Updated : Dec 22, 2014, 07:18 AM IST
Central Railway on the night of Saturday and wee hours of Sunday gave finishing touches to one of its longest-running electrical engineering works as the entire section between Thane and CST was tested to run on 25,000 Volt Alternating Current (AC).
The slow lines between CST and Mumbra and the fast lines between CST and Thane currently run on 1500 Volt Direct Current, which is obsolete and also completely out of sync with the rest of the Indian Railways network which runs on 25,000 Volt AC traction.
When was work undertaken?
According to officials, the test-charging took place between 11pm on Saturday and 6am on Sunday and went off smoothly. They expect the Commissioner of Railway Safety to give the all-clear to the project very soon. The report has been sent to CRS Chetan Bakshi, said CR officials. If the go-ahead is obtained for the project, then all CR's lines except Harbour line will run AC traction. Harbour line would take at least another couple of years, said officials.
What was the scale of operation?
"It is a huge process and involved more than 600 people. All the electrical systems that run on DC are switched off and disconnected and then their AC counterparts are connected. The power is then charged and trains- 2 AC locals and AC engines in this case- were run to check if everything was in place. It turned out as expected," said the official.
How was the testing done?
The block started at around 11:45pm on Saturday as all local trains running on the circuit either had to be retired to the stabling lines in the carshed or had to cross the CST-Thane stretch. Once this was achieved the test runs began.
"The tests took place between 2:30am and 3:30am. Then all the AC equipment was switched off, disconnected and their DC counterparts re-attached to the system. By 5:55am, CR was back to the situation that prevailed before the test-charging began," said the official.
When will CR trains run on alternating current?
CR will require nine additional trains running on AC once the switch is made. Of this, CR officials said, five rakes are in place and another four should be handed over by WR in the next few days. "Then we are ready to begin the day we get permission from the CRS," said an official.
Mega savings
Officials believe the switch DC-AC switch between CST and Thane will save CR at least Rs 100 crore in power bills every year.
CR runs about 1,660 local services, 410 long-distance trains and 346 freight trains every day and the electricity bill for the year 2013-14 was Rs 1432 crore. The usage was 1,890 million units.
After conversion of Kalyan-Thane section, CR has saved Rs 112.74 crore (25.8 million units) for the financial year ending March 2014
Other benefits
With duality of AC and DC gone, a single system will reduce train failures
Long-distance trains will save on time as they don't have to change from DC to AC while exiting CR's Mumbai network
AC will integrate CR's Mumbai division with the rest of the Indian Railways network. Lower maintenance of overhead wires and other structures