All-day performance checks of the new signalling system on the North-South Line are necessary to "work out teething issues", rail operator SMRT said in a blog post yesterday.

The communications-based train control signalling system allows trains to run closer together and arrive at intervals of up to 100 seconds during peak hours, instead of 120 seconds currently.

The checks were first conducted during off-peak hours in March, and progressed to all-day weekday testing last month.

"As there are limited engineering hours each day (from 1.30am to 4.30am), it is not possible for us to accumulate adequate testing hours if we do not run the new signalling system during weekdays," said the rail operator.

It added that trains fitted with the new system were put through "rigorous checks" before being cleared for passenger service.

The issues faced by the North-South Line could potentially resurface when the Tuas West Extension (TWE) opens on June 18.

While the TWE will bring convenience to those working in the Tuas industrial area, it could spell even more challenges for SMRT.

The TWE will operate on the new signalling system, which may result in problems such as delays between stations, train carriages stopping slightly longer at platforms and the platform screen doors and train doors not opening promptly.

However, Mr Siu Yow Wee, director of station operations, is confident that these issues will be handled well. "LTA, SMRT and the engineers from (signalling system supplier) Thales are working very closely, with all hands on deck, so that we can respond quickly to any situation that may arise,"he said.

He was speaking to reporters yesterday at the Gul Circle MRT station, together with a team of station managers. The station is one of the four new MRT stations - the others are Tuas Crescent, Tuas West Road and Tuas Link - on the TWE, which is expected to serve 100,000 commuters daily.

On the ground level, more manpower has been deployed. Extra service ambassadors will help commuters get used to the layout of the new stations, and respond to any issues.

"All station staff are trained to be on standby and we are always ready to attend to emergencies or faults," said Mr Sawal Majid, 47, the senior station manager at Gul Circle station.

Preparations have been taking place daily since February last year in order to get the 7.5km-long extension up and running. The TWE project involves both experienced SMRT staff and new hires like Mr Francis Arnold, 31, the station manager of Tuas West Road station.

"I am excited and fortunate to be part of the pioneer team launching the Tuas West Extension, and I am learning a lot from the senior managers," said Mr Arnold.

When asked for their thoughts about the train delays, Mr Wong Kin Kwok, 41, the station manager of Tuas Link station, said: "We will do our best and try to improve the situation."

This view was echoed by SMRT on its blog, where it sought the understanding of commuters during these tests.