Updated

The cause of the power outage last Sunday at the Super Bowl in New Orleans was an electrical relay device.

Power at the Superdome was lost during the third quarter, causing a delay of 34 minutes. About half of the building's lights went out.

Entergy New Orleans on Friday said the device was specifically installed to protect the Superdome equipment in the event of a cable failure between the switchgear and the stadium. The relay device triggered, signaling a switch to open when it should not have, causing the partial outage.

The device has since been removed.

"While some further analysis remains, we believe we have identified and remedied the cause of the power outage and regret the interruption that occurred during what was a showcase event for the city and state," said Charles Rice, president and chief executive officer of Entergy New Orleans.

The company said the relay device worked without issue during the Sugar Bowl, New Orleans Bowl and the Saints' regular-season finale against Carolina.