A trial of the automatic signalling system on the full stretch of East-West Metro (Green Line) began on Sunday, in what Metro engineers claimed was a “significant step” towards linking Sector V and Howrah Maidan, the two terminal points of the 16.6km corridor.
The Kolkata Metro Rail Corporation (KMRC), the implementing agency of the project, has sought a 45-day suspension of commercial services — from February 8 to March 24 — on the route to expedite the trial.
But the Metro authorities are against a prolonged suspension of commercial services. They want to run commercial services and conduct the trial together.
Commercial services were suspended on Sunday (January 12). The carrier has announced that they will remain suspended next Sunday (January 19), too.
“A complete traffic block on two Sundays was sought by the KMRC. It was immediately granted. A request for full closure of Green Line services from February 8 to March 24 has been submitted by the KMRC. The demand has not been approved so far.,” said a senior Metro official.
“We want commercial service and trials to go side by side.”
The east-west Metro corridor is now functional in two parts, between Sector V and Sealdah (Phase 1) and between Howrah Maidan and Esplanade (Phase 2). Commercial services are not run in Phase 1 on Sundays.
A Metro engineer said the first step of the exhaustive tests would involve “off-loading the old software and uploading the new software for a unified corridor”.
“This means upgrading the new system at all 12 stations in the corridor and at the control centres in Sector V and Howrah Maidan,” the engineer said.
Once the new automatic train supervision software is installed everywhere, tests will be conducted on “track locking, signal blocking, track blocking, approach locking and tunnel ventilation system interlocking”.
The next step will involve testing the platform screen doors. “It is the most time-consuming part of the trial,” said an engineer. For now, it has been planned for January 18-19.
Metro sources said commercial services may also remain suspended on Sundays after January 19.
The communication-based train control (CBTC) system, installed in East-West Metro, is an advanced anti-collision system, said railway engineers.
Now, there are separate CBTC systems for the two phases of the Green Line. There is a missing link between Sealdah and Esplanade, where a stretch in Bowbazar has seen four incidents of water leakage and soil subsidence since 2019.
“At present, the rakes operating in the two parts cannot communicate with each other. Completion of the CBTC work will turn the entire route into a single unit. Then, a rake at Sealdah can see a rake in, say, Esplanade,” said an engineer.