(NEWSER) – Power company officials revealed today the cause of the infamous Super Bowl blackout, and took full responsibility for it. A faulty relay device designed to prevent a failure in the Superdome's electric cables was apparently to blame, the AP reports. Entergy New Orleans officials said they were replacing the device, but added that it had worked fine in previous large-scale events, like January's Sugar Bowl.

The Superdome has a direct line to Entergy, but it splits into two cables in a building called "the vault" near the stadium. Apparently the switching mechanism is what broke. Entergy's explanation comes on the same day it's scheduled to appear before regulators to explain itself.