The team comprising engineers from the Land Transport Authority (LTA), SBS Transit, and the signalling system supplier Siemens has identified and rectified the signalling system fault which occurred yesterday at Bayfront Station on the Downtown Line (DTL), allowing normal train services to resume from the start of service hours this morning.
2. The team traced the fault yesterday to a synchronisation issue between two sets of signalling equipment – the Temporary Speed Restriction Manager and the Trackside Automatic Train Control System. This triggered an automatic safety response from the system, which caused a speed restriction and the prohibition of automatic train movement over the affected stretch between Promenade and Downtown Stations.
3. To minimise inconvenience to commuters, the team worked through the night after service hours to rectify the fault. Two track circuits at Bayfront Station were manually synchronised. This restored the synchronisation issue between the two sets of signalling equipment. We were then able to lift the speed restriction imposed between Promenade and Downtown stations. The team also operated empty test trains through the affected stretch through the night to verify that the issue had been fully resolved.
4. 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.