User Groups

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Houston User Group Meeting, May 2018

High Voltage Arc Flash Analysis & Arcing Fault Hazard Evaluation was the focus of the Houston User Group Meeting on May 8, 2018.

OSHA has placed the requirement to perform arc flash hazard analysis on utility systems for voltage levels above 1 kV. Heavy industrial and renewable energy collector systems operating at voltage levels above 15 kV have similar requirements to perform arc flash incident energy calculations. This analysis may be outside the scopes of IEEE 1584 and NFPA 70E calculations.

The presentation provided an overview of the calculation methods available for line-to-ground (LG) open-air arc faults in distribution and transmission systems, and introduces ETAP proprietary methods developed for the calculation of the incident energy in 3-phase enclosed equipment with nominal voltage between 15 to 38 kV. 

The presentation also provided information on the relationship between NESC C2 2017 open-air LG arc fault tables, gap between conductors, minimum approach distance, altitude, and transient overvoltage correction factors. 

ETAP ArcFault™ module was presented with examples of open-air arc fault calculations. Result comparison and validation between ArcFault and OSHA 1910.269 Annex E table 3 were discussed.