(Reuters) - Power company Entergy Corp said Friday it has traced the cause of Sunday's Super Bowl power outage to an electrical relay device.

The device was specifically installed to protect the Superdome's equipment in the event of a cable failure between the switchgear and the stadium, Entergy said.

The relay functioned without issue during a number of other events, including the New Orleans Bowl, the New Orleans Saints-Carolina Panthers game, and the Sugar Bowl.

But during the Super Bowl on Sunday, the relay device triggered, signaling a switch to open when it should not have, causing a partial power outage in the building.

(Reporting By Scott DiSavino; Editing by Gerald E. McCormick)