I’ve probably been to hundreds of product demonstrations and training courses in my twenty year career in the electrical industry but none has left such a lasting impression on me as the one I witnessed this March. At ABB’s Automation & Power World show in Orlando, FL this year, I sat in on a product and service demonstration presented by Steve Scala, a protection & controls expert for ABB Service. Steve was presenting the benefits of upgrading older medium voltage switchgear with modern technology. He was pointing out the benefits of replacing older breakers with modern Roll-in Replacement breakers and upgrading older protection relays with the new ABB Relion family of relays. What stood out, however, was when he strongly recommended adding ABB’s REA Arc Flash Protection System every time you upgrade switchgear. “It’s simple really,” as Steve described, “the REA relay saved my life.”
Arc flashes are a serious concern in the electrical industry. Arc flashes are a result of a fault in an electrical system where a high voltage shorts rapidly to ground. The resulting arc plasma can exceed temperatures of 35,000 °F and the energy released can vaporize copper conductors, melt steel barriers, and create an explosion as the plasma expands outwards with extreme force. Workers and operators in the vicinity of these arc faults are exposed to explosive, high temperature forces which can lead to serious injury or death.
Steve told the assembled group about an event that occurred in 2010 that made him a true believer in the benefits of the REA relay. ABB had assisted in the upgrade a line-up of 13.8kV metal clad switchgear at a major university in the Northeast United States. The existing gear was installed in 1987 and was an outdoor design with a common aisle between two rows of switchgear and enclosed in a NEMA 3R enclosure. ABB had completed the upgrade of the switchgear, adding a complete ABB REA Arc Protection System, three months before the event occurred. On the day of the event, Steve and five other people were inside the enclosure, touring the completed project, when an arc fault occurred in one of the switchgear line-ups.
An arc fault of this magnitude would normally have severely damaged the switchgear line-up and caused injury or death of the people inside the enclosure. Instead, the REA relay system did exactly what it was designed to do and cleared the fault by opening the source breaker in 50.2 milliseconds. The arc light and fault current were sensed by the REA system in less than 2.5 milliseconds and the breaker opened in 48 milliseconds. Instead of severely damaging the gear, the REA system minimized the impact to the equipment to where it could be fully restored in less than 12 hours. More importantly, Steve and each of the others touring the gear walked out alive and uninjured.
The Bottom Line
It’s easy to understand why Steve’s story made such an impact on me. Upgrading an existing line-up of switchgear by adding the REA Arc Protection System can have huge benefits. Equipment damage can be minimized, power restoration can occur quicker, and lives may even be saved with this technology. Even though I wasn’t there to witness the event in 2010, I’m also now a true believer in the benefits of the ABB REA relay.
Steve Scala works as a Business Development Manager for Protection & Controls as part of ABB Medium Voltage Service. He works out of Coral Springs, FL