PUTRAJAYA: A circulating current has been identified as the main cause of the blackout at the Kuala Lumpur International Airport Terminal 2 on August 28.
The Transport Ministry stated that the finding resulted from a technical investigation conducted by Malaysia Airports Holdings Berhad, with the Cabinet noting the report on Wednesday.
“MAHB’s technical investigation found that the main cause of the incident was the presence of a circulating current along the cable route between the 33kV substation supplying power to KLIA T2 and the 11kV substations at the terminal.”
“This condition caused localised heating at the cable termination, which led to a flashover incident.”
High soil resistivity was also identified as an indirect contributing factor because it prevented effective dissipation of current into the ground, thereby increasing thermal stress on sheath wires.
MAHB’s technical team implemented immediate measures following the incident, including repairing all cable terminations and installing sheath voltage limiters at cross bonding locations to reduce circulating current effects.
“Another step was enhancing the maintenance regime by incorporating partial discharge tests and thermographic inspections into the planned preventive maintenance programme for power cables.”
MAHB has identified long-term improvement measures to enhance system safety and reliability, including studying the feasibility of installing an Automatic Transfer Switch system to speed up backup power supply.
Other measures involve shortening the planned preventive maintenance interval for genset load testing at Gateway@klia2 from every three months to every two months to improve reliability and enable early detection of flashover incidents.
“Also, conducting a comprehensive study of soil resistivity along the cable routes, including seasonal analysis and the effectiveness of earthing and cross bonding systems, to better control circulating current risks and improve earthing efficiency in the future.”
The ministry confirmed that MAHB has verified no critical airport operations were affected by the incident.
“MOT will continue to monitor the implementation of MAHB’s follow-up measures to ensure the highest level of safety, efficiency and reliability of systems at KLIA.”
“The government’s main focus is to ensure this incident is addressed promptly with effective preventive measures to avoid recurrence.”
KLIA Terminal 2 experienced a power outage at 2.15 pm on August 28, which Transport Minister Anthony Loke described as completely unacceptable due to its impact on the country’s image. – Bernama
