Faulty wiring the culprit behind SGX's November market breakdown

Blame it on a voltage sag.

A power outage which rocked the Singapore Exchange early in November last year has been blamed on faulty power systems.

Findings from the Board Committee of Inquiry’s probe showed that the power outage, which was triggered by a voltage sag in both power lines to the SGX Primary Data Centre (PDC), was caused by a combination of a faulty component in the emergency backup power supply generator and the inability of downstream switches to cope with this malfunction.

The BCOI’s report noted that the PDC’s power supply is designed with two independent power sources, each backed by an emergency power supply generators.

In addition, the PDC has Static Transfer Switches (STS) to seamlessly draw power from either source in the event that there is a fault with either the generator or utility power source.

During the outage, though, the PDC experienced simultaneous voltage dip across the two independent substations supplying power to the centre. However the STS were unable to cater for an out-of-phase power transfer.

The outage was blamed on “a gap in the design of the power systems” at the PDC.

The BCOI urged the SGX to make further improvements beyond the root cause to enhance overall resiliency and incident management.

These include enhancing processes and resources to improve business continuity, incident management and the timeliness and effectiveness of crisis communications.