NEW ORLEANS - The Superdome's power company took the blame Friday for the Super Bowl blackout, saying the cause was a faulty device that had been installed in its switching gear and designed to prevent a failure of electric cables leading to the stadium.

Officials of Entergy New Orleans, a subsidiary of New Orleans-based Entergy Corp., said the device, called a relay, had been installed to protect the Superdome from a cable failure between the company's incoming power line and lines that run into the stadium.

Company officials said the device performed without problem during January's Sugar Bowl and other earlier events.

They said the device has been removed and replacement equipment will be installed.

The power failure at Sunday's big game cut lights to about half of the stadium for 34 minutes, halting play between the Baltimore Ravens and San Francisco 49ers.

Officials of the power company and the company that manages the stadium for the state had said earlier this week that they believed the problem originated in the switching gear, which is housed in a building known as "the vault" near the stadium. The Superdome has a direct line feeding from a nearby Entergy power substation. Once the line reaches the vault, it splits into two cables that then go into the Superdome.