Fault in train control centre identified

27 April 2012 2:02PM

KiwiRail has concluded its preliminary investigation into the power outage at its National Train Control Centre (NTCC) in Wellington which caused widespread disruption on the Auckland rail network yesterday afternoon.

Chief Executive Jim Quinn says the outage was caused by a faulty uninterruptable power supply (UPS) unit which feeds the Auckland network control desks. The faulty unit was immediately removed from service and a replacement is being installed today.

“While we responded as quickly as possible to remedy the situation and had the network up and running again in just over an hour, the existing power system design simply wasn’t robust enough and we are taking immediate steps to further minimise the chance of this type of incident happening again.”

“We will undertake an independent review of the NTCC power system design and recommend necessary changes to ensure further robustness of the power supply.”

Mr Quinn said in the meantime a range of immediate steps were already underway, including the replacement of the faulty unit, which should ensure that the system will operate as normal.

“We again apologise to all the commuters who were affected by this outage last night.”

Mr Quinn said this sort of outage had never occurred in the NTCC before.

Summary of findings:

At 1603 Hours on 26 April 2012 a power failure in part of KiwiRail’s National Train Control Centre (NTCC) rendered control of the Auckland signalling system inoperative. The same power outage also caused outages on the train radio system for the Auckland Suburban Area.

KiwiRail Engineering staff were onsite in a timely fashion closely followed by the Wellington Railway Station electrical contractor.

The cause of the outage was a faulty Uninterruptable Power Supply (UPS) unit. UPS are installed to allow critical equipment (eg computers) to continue operation in the event of a mains power outage.

Immediate work has been undertaken to remove the faulty UPS from service. A replacement unit is being installed today.

Further work will be undertaken to ensure the robustness of the NTCC power system which is anticipated to be completed within a week. In addition an independent review of the power system’s design and resilience will be undertaken.

Sequence of Events:

1603 Hours:    Power to the Auckland Control desks lost affecting signalling control and radio communication
1605 Hours:    First text update sent out
1608 Hours:    Engineering staff onsite
1620 Hours:    Wellington Railway Station contract electricians arrive on site
1630 Hours:    Auckland backup systems used to move trains to platforms
1650 Hours:    Power restored
1655 Hours:    NIMT (South Routes) restored to full operation
1720 Hours:    West Line restored to full operation

Media Contact: Jenni Austin, Senior Communications Advisor, 021 961 495