“Smart” Relay Caused the Super Bowl Blackout

February 07, 2013 by Jeff Shepard

Entergy New Orleans, Inc. announced today that it has traced the cause of Sunday's outage to an electrical relay device reportedly manufactured by S&C Electric Co. that was to have prevented just such occurrences. Root-cause analysis of the failure is still underway. The switching gear is housed in a building near the stadium that receives power from a nearby Entergy substation. Once the line reaches that point, it splits into two cables that go into the Superdome. The device was specifically installed to protect the Superdome equipment in the event of a cable failure between the switchgear and the stadium.

While the relay functioned without issue during a number of high-profile events — including the New Orleans Bowl, the New Orleans Saints – Carolina Panthers game, and the Sugar Bowl — during the Super Bowl game, the relay device triggered, signaling a switch to open when it should not have, causing the partial outage. This device has since been removed from service and new replacement equipment is being evaluated.

In a joint-statement issued by Entergy and SMG, the management company for the Superdome, the electrical monitoring systems at the stadium performed as designed, it is commented: "Shortly after the beginning of the second half, a piece of equipment that is designed to monitor electrical load sensed an abnormality in the system. The fault-sensing equipment activated where the Superdome equipment intersects with Entergy's feed into the facility.

"Once the issue was detected, the sensing equipment operated as designed and opened a breaker, causing power to be partially cut to the Superdome in order to isolate the issue. Backup generators kicked in immediately as designed. Entergy and SMG subsequently coordinated start up procedures, ensuring that full power was safely restored to the Superdome."

According to a story on Sports Illustrated, Superdome officials warned just months before the Super Bowl that the venue's electrical system could suffer a power outage and rushed to replace some of the equipment ahead of the big game. Tests on the electrical feeders that connect incoming power from utility lines to the stadium showed decay and "a chance of failure," state officials warned in a memo dated Oct. 15. The documents, obtained through a records request by The Associated Press, also show the utility that supplies the stadium expressed concern about the reliability of the service before the Super Bowl.

The memo said utility Entergy New Orleans and the Superdome's engineering staff "had concerns regarding the reliability of the Dome service from Entergy's connection point to the Dome." The memo was prepared for the Louisiana Stadium & Exposition District, the state body responsible for the Superdome.

The power failure at Sunday's Super Bowl game cut lights to about half of the stadium and delaying play for 34 minutes. "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.