Several schools in the Spryfield area of Halifax closed for the day Friday due to a power outage in the area.

Elizabeth Sutherland, Rockingstone Heights, J.L. Ilsley and Cunard Junior High were closed, said the Halifax Regional School Board.

Nova Scotia Power said a failed insulator at the Spryfield substation was responsible for an outage that affected more than 11,000 customers in the Halifax area Friday morning.

Tiffany Chase, speaking for the utility, said there were two transformers at the substation that needed repair.

Power has been fully restored.

Chase said she wasn't sure what caused the insulator to fail.

The insulator is supposed to protect other equipment at the substation if there's a power surge or other problem, said Chase, sort of like a trip switch on a power bar.