Problems with a generating station in Campbell Industrial Park caused instability in Hawaiian Electric Co.’s grid resulting in power outages in Leeward and Windward Oahu Monday.

Outages started mid-morning, and power was fully restored by 12:30 p.m., according to HECO.

HECO said the station at Campbell Industrial Park is owned by AES, an independent company that sells power to HECO, and is the single largest generating unit in the system.

The generating station at industrial park went offline at around 9:50 a.m., triggering instability in the system.

To restabilize the grid and prevent a potentially bigger, island-wide outage, HECO said power was disconnected to several neighborhoods.

Affected neighborhoods included Ewa, Mililani, Wahiawa, Waipahu, Kalihi, Pacific Palisades, Kailua, Kaneohe and Waihee.

 The majority of the outages were restored  by 10:30 a.m. However,  5,200 homes and businesses remained without power until later in the day.

A separate, unrelated outage was also reported in Kaaawa at around 9:30 a.m. It affected nearly 800 homes and businesses.