2 mile-long airport feeder cable system with multiple defects is now reliable

OVERVIEW 
Quality issues on new critical cable system identified with Factory Grade® technology and repaired
CHALLENGE 
International airport cable system installed with multiple hidden defects threating traveler safety and grid reliability.
RESULTS IMCORP’s 
IMCORP’s Factory Grade® technology effectively pinpoints multiple substandard components and confirms repairs meet industry
standards preventing multiple outages at a major international airport

In 2017, a major southeastern international airport was shut down due to a power outage
attributed to a fault found in the underground cable system feeding the airport. No utility wants
to experience this kind of negative publicity. The normally bustling airport handles 275,000
travelers a day plunged into darkness for nearly 11 hours, leaving some passengers stranded
on the tarmac for hours. Utilities take precautions to prevent this type of scenario but are still
vulnerable to critical outages due to hidden defects. One way to prevent such an incident is to
assess the condition of underground assets, whether new or aged, using a test comparable
to the manufacturers’ standards. IMCORP’s Factory Grade® technology is the assessment
that can qualify installed cable systems meet those standards.

Learning from the 2017 experience, another southeastern utility with a major international
airport decided to proactively perform the IMCORP Factory Grade® test on newly installed
cable systems. The utility already had extensive positive experience with this approach on
other new and aged cable systems, but this was their first-time checking airport cable systems.
According to IMCORP database analytics on over 180,000 cable assessments, up to 20% of
newly installed 3-phase cable systems have at least one substandard component. The utility
expected to find some minor issues with splices and terminations, but nothing prepared them
for the extent of the problem they uncovered.

The subject airport feeder was approximately 12,000 ft in length, having multiple connection
points linked through an underground conduit and vault system. Long cable lengths generally
make achieving factory comparable test and locating defects difficult. However, the IMCORP
Factory Grade® technology was able to overcome these challenges through the use of
superior sensors, adaptive machine learning techniques, and digital location matching
technology.

Working with the utility and contractor crews, IMCORP assessed all the newly installed cable
segments. While the joints and terminations performed better than average and a few repairs
were made onsite, two different types of factory defects were found at multiple cable locations
necessitating the removal of two sections. IMCORP was able to pinpoint all of the serious
insulation issues and confirm repairs met industry standards, preventing multiple major
outages at an international airport, and demonstrating the need to perform an effective cable
condition assessment during the commissioning process.