The Entergy statement, which points the finger at the manufacturer of the relay, says Dr. John A. Palmer of Palmer Engineering & Forensics found "behavior of the device in a manner contrary to the published functionality of the device constitutes a design defect."
The relay device was installed in the Entergy vault just outside the Dome in January as part of last-minute upgrades to the stadium's electrical system, according to WWL-TV's Mike Pearlstein.
The following is the full news release from Entergy:
Independent Forensic Analysis Confirms Partial Power Outage During Super Bowl Caused by Relay Device
New Orleans, La. – An independent, third-party forensic analysis commissioned by Entergy New Orleans, SMG and the Louisiana Stadium and Exposition District to investigate the cause of the partial power outage during Super Bowl XLVII has confirmed that the cause of the outage was the "misoperation" of a relay device. The analysis was performed by Dr. John A. Palmer of Palmer Engineering & Forensics.
Highlighting what he characterizes as a "design defect" in the relay, Dr. Palmer’s report states on page five, "Behavior of the device in a manner contrary to the published functionality of the device constitutes a design defect."
Dr. Palmer’s report identifies the primary cause of the power disruption and three contributing factors. They are as follows:
1. The cause of the outage was a misoperation of the relay.
2. A contributing factor to the misoperation of the relay was the unstable operating condition of the relay around the set point of the subject relay, which was a design defect.
3. A contributing factor to the outage was the inappropriate setting of the relay, which was the factory default setting.
4. A contributing factor to the inappropriate setting was inadequate communication between the manufacturer and the utility.
The relay device, which is located in a vault outside of the Mercedes-Benz Superdome, was a component in the switchgear that was placed into service in December 2012 after being inspected, tested, and commissioned by the manufacturer. The relay was taken out of service following the Super Bowl. In addition, Entergy New Orleans has confirmed that there are no other such devices installed elsewhere on its system.
"We are pleased that Dr. Palmer's independent analysis has verified the root cause of the outage and confirmed that the relay operated in an unintended and unpredictable manner," said Charles Rice, president and CEO of Entergy New Orleans. "It has been our objective all along to identify the cause of the outage, learn from it, and prevent such an occurrence from happening again. The device has been permanently removed from service."