LOUISVILLE, Ky. (WDRB) -- Metro Corrections is operating normally again after a power outage Wednesday afternoon. 

FOP President Tracy Dotson said the facility lost power about 3:30 p.m. Thursday. It was fully restored around midnight. 

Metro Corrections Assistant director Steve Durham confirms that the jail switched from main power to emergency power as part of an annual test of the backup system. But a power surge meant they were unable to get the main power back on line. 

Crews restored power to lights and security cameras after about 45 minutes, according to Durham. But all control of doors and elevators was taken off line and officers had to use keys to open and close doors until the system was back on line.

Durham said key control is the standard backup for power disruption of any type. 

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