While some conductor manufacturers are cutting back or eliminating their research facilities, Southwire is actively improving its existing facilities to bring top-of-the-line products to utility customers. Recent enhancements to the industry-leading research capabilities of Southwire's D.B. Cofer Technology Center include leading-edge vibration (self damping) testing of overhead conductors such as aluminum conductor, steel-supported (ACSS) products.

The newly enhanced Cofer Center vibration-test facility features a 32-m (106-ft) conductor span. In this span, a computer-controlled vibration-shaker mechanism initiates conductor motion and state-of-the-art sensors measure the resulting conductor vibration. The laboratory vibration closely simulates the real-world vibration caused by wind acting on the power line. This facility is initiating original research into the need to prestress ACSS to get the inherent vibration-resistance benefits of ACSS. At a time when some utilities are replacing conventional self-damping conductors with prestressed ACSS for increased reliability, this work could help to shape the future of overhead conductor practices where vibration is a concern.

“We know the effects of prestressing ACSS,” says Southwire Energy Division's Chief Engineer Paul Springer. “In many countries, ACSS that is prestressed at installation is routinely installed without vibration dampers. In this study, we are investigating the vibration behavior of ACSS installed without prestressing.”

The ACSS vibration study is in its preliminary stages. Meaningful data is expected early in 2013. The data is important because answers from this study may allow users to reduce ACSS installation costs by avoiding or reducing prestressing. Favorable vibration data also may allow users to reduce or avoid the cost of adding separate vibration-damping hardware to ACSS installations.

Springer's leadership provides a solid foundation for vibration testing at Southwire. Springer previously managed the mechanical testing laboratory and the conductor dynamics laboratory at the National Electric Energy Testing Research and Applications Center (NEETRAC) in Forest Park, Georgia, U.S. There, he was the principal investigator on advanced NEETRAC projects related to overhead system failure analysis, system dynamics, and countermeasures for galloping and Aeolian vibration. Springer has drafted significant sections of IEEE conductor standards and serves on several industry committees.

For more information, visit www.southwire.com.