SINGAPORE: The Land Transport Authority (LTA) on Tuesday (Apr 26) said overnight checks show a massive power trip that crippled parts of the MRT network on Monday evening was due to a power fault within the western sector of the North-South and East-West Lines and not because of a power dip.
SMRT had earlier said a power dip at the Buona Vista power intake station caused the power trip.
In a statement issued to the media, LTA said preliminary investigations indicate that the 22kV circuit breakers at Buona Vista station tripped.
"As the Buona Vista power intake station supplies power to the western sector of the North-South and East-West Lines (NSEWL) and parts of the Circle Line (CCL), this affected train services on the NSEWL from Buona Vista to Joo Koon and Jurong East to Kranji, and CCL from Harbourfront to Caldecott," LTA said in a statement.
"As the Bukit Panjang LRT system receives power from the same source through Choa Chu Kang on the NSEWL, it was similarly affected," LTA said.
It added that more checks will be carried out after train operations end on Tuesday, and it is working with the public transport operator to investigate the cause of the power faults.
Several MRT stations along the East-West, North-South and Circle Lines, as well as the Bukit Panjang LRT line were hit by the power trip at 7.53pm on Monday. As a result, some commuters were stuck on stalled trains for up to half an hour. It was the first time that train on three MRT lines, plus an LRT line, were disrupted at once.
Four trains on the Bukit Panjang LRT line were stalled between stations due to the power trip and 150 passengers were evacuated safely from trains.
All affected stations were without power except for emergency lighting, according to the public transport operator.
SMRT said on Monday that it was still investigating the cause of the power trip.