Synchronisation issue between signalling equipment led to recent Downtown Line delay

SINGAPORE — Train delays along the Downtown Line (DTL) on Thursday (March 1) were due to a “synchronisation issue between two sets of signalling equipment”.

In a joint press statement on Friday evening, the Land Transport Authority (LTA) and SBS Transit said the synchronisation issue resulted in a “speed restriction and the prohibition of automatic train movement over the affected stretch between Promenade and Downtown stations”.

A team comprising engineers from the LTA, SBS Transit and the signalling system supplier Siemens then worked through the night after service hours to rectify the situation. Normal services resumed by Friday morning.

The statement said two track circuits at Bayfront station were manually synchronised on Thursday night. This resolved the synchronisation issue between the two sets of equipment – the Temporary Speed Restriction Manager and the Trackside Automatic Train Control System.

“The team also operated empty test trains through the affected stretch through the night (on Thursday) to verify that the issue had been fully resolved”.

The statement added: “Although the engineering teams have identified the immediate cause of the signalling fault and we were able to resolve the issue, Siemens will continue its investigations into the root cause of the failed synchronisation of the signalling equipment to prevent a recurrence.”

Commuters were first alerted to a fault on the DTL when SBS Transit first announced there was a delay on the line at 6.51 am on Thursday. The problem persisted through the day, until the end of service hours.

Besides the delays on the DTL, Thursday saw commuters hit with a double whammy after ride-hailing firm Grab was hit by a technical glitch. However, services on Grab were fully restored by 11am the same day.