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Report on High Energy Arc Fault Experiments: Experimental Results from Medium Voltage Electrical Enclosures



Gabriel Taylor, Anthony D. Putorti Jr., Scott Bareham, Edward Hnetkovsky, Kenneth Hamburger, Nicholas Melly, Mark Henry Salley, Christopher U. Brown, Wai Cheong Tam, Eric Link, Michael Selepak, Philip Deardorff, Kenneth Miller, Paul Clem, Byron Demosthenous, Austin Glover, Chris LaFleur, Raymond Martinez, Anthony Tanbakuchi


This report documents an experimental program designed to investigate High Energy Arcing Fault (HEAF) phenomena for medium voltage electrical switchgear containing aluminum conductors. This report covers full-scale laboratory experiments using representative nuclear power plant (NPP) three-phase electrical equipment. Electrical, thermal, and pressure data were recorded for each test and documented in this report. This report covers four of the fourteen planned medium voltage electrical enclosure tests. Subsequent reports will document the additional tests performed in the future. The experiments were performed at KEMA Labs located in Chalfont, Pennsylvania. The experimental design, setup, and execution were completed by staff from the United States Nuclear Regulatory Commission (NRC), the National Institute of Standards and Technology (NIST), Sandia National Laboratories (SNL) and KEMA. In addition, representatives from the Electric Power Research Institute (EPRI) observed some of the test setup and execution. The HEAF tests were performed on four near-identical units of General Electric metal-clad medium voltage switchgear. The three-phase arcing fault was initiated on the primary cable connection bus. All four tests used the same system voltage (6.9 kV) but varied the current and duration. Real-time electrical operating conditions, including voltage, current and frequency, were measured during the experiments. Heat fluxes and incident energies were measured with plate thermometers and slug calorimeters at various locations around the electrical enclosures. Internal enclosure pressures were measured during the experiments. The experiments were documented with normal and high-speed videography, infrared imaging and photography. Insights from this testing included timing information related to enclosure breach, event progression, mass loss measurements for electrodes and steel enclosures, peak pressure rise, particle analysis, along with visual and thermal imaging data to better understand and characterize the hazard. These results will be used in subsequent efforts to advance the state of knowledge related to HEAF.
Technical Note (NIST TN) - 2188
Report Number


High Energy Arcing Fault, Arc Flash, Electrical Enclosure, Electric Arc, Fire Probabilistic Risk Assessment


Taylor, G. , Putorti Jr., A. , Bareham, S. , Hnetkovsky, E. , Hamburger, K. , Melly, N. , Salley, M. , Brown, C. , Tam, W. , Link, E. , Selepak, M. , Deardorff, P. , Miller, K. , Clem, P. , Demosthenous, B. , Glover, A. , LaFleur, C. , Martinez, R. and Tanbakuchi, A. (2021), Report on High Energy Arc Fault Experiments: Experimental Results from Medium Voltage Electrical Enclosures, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed May 23, 2024)


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Created November 29, 2021, Updated November 29, 2022