BACOLOD CITY, March 26 -- Tripping of the transmission lines of the Central Negros Electric Cooperative (Ceneco) and the National Grid Corp. of the Philippines (NGCP) led to massive power interruptions in most parts of Bacolod and the neighboring localities past midnight on Tuesday.

Jose Taniongon, manager of Ceneco's Unified Engineering, Operations and Maintenance Department, said in an interview that three out of the four 69 kilovolt (KV) transmission lines went offline.

"There was a short circuit and the installed protective equipment prevents damage to the line by tripping," he added.

Taniongon said the minimal rain early Tuesday morning triggered a breakdown of the insulator, which is supposed to protect the 69KV line from short c...