![]() ![]() Caution and a practical interpretation is recommended. “Sustainable arcs are possible but less likely in three-phase systems operating at 240V nominal or less with an available short-circuit current less than 2000A.” This results in a very conservative requirement for identifying the potential exposure of a Qualified Electrical Worker to an arc flash hazard when working on 208VAC three phase systems. The 2002, 125 kVA transformer guideline related to not having to complete calculations has been removed and replaced with following quote: With respect to low voltage less than 240V three-phase electrical equipment. Some comments are also provided related to the updated electrode and box configurations used and what electrical equipment and work tasks they may apply to. Some of the key details and parameters from the 2002 to 2018 Edition are listed below. Electrical Engineer with suitable experience or the resulting calculations may be incorrect or too conservative. The challenge now is the new IEEE 1584 2018 Edition utilizes new updated formulas and specific parameters have changed that require realistic and reasonable oversight by a P.Eng. Things have changed and as of 2018 I would estimate that all engineering consulting firms across Canada have completed arc flash incident energy analysis studies across all industry sectors. At the time (2005) none of the engineering consulting firms (over 20 that I contacted) that EnCana was using even knew what an arc flash was and had not completed IEEE 1584 based arc flash hazard incident energy analysis studies. Following attending that presentation and with additional research at the time I discovered that there were formulas for calculating “arc flash.” This led me to the IEEE 1584 2002 Edition while working for EnCana Corporation as a Staff Electrical Engineer. My history with arc flash started in 2004 at an IEEE PCIC Conference where I attended a presentation on the 2004 Edition of NFPA 70E Standard for Electrical Safety in the Workplace. Information provided below is the authors interpretation based on specific review and interaction and discussion with colleagues and those involved in the IEEE 1584 Technical Committee. You are cautioned to ensure that realistic interpretations and good engineering judgement are utilized when reviewing the application of the updated IEEE 1584 2018 Edition. Some of the information presented below needs careful consideration, if conservative assessments are made incident energy levels could go up by 200%. ![]() It is critical that company’s follow a strict Management of Change (MOC) process when reviewing the potential changes to existing arc flash hazard incident energy analysis studies. ![]() The formulas provided do not apply to single phase systems or DC. The new 2018 formulas apply to similar base parameters with a slight change in the fault current levels considered depending on the voltage level. The formulas apply to electrical equipment from 208VAC to 15kV three phase, 50 or 60 HZ. The First Edition was published in 2002 and established formulas for the basis of calculating a predicted incident energy and an arc flash boundary distance related to an abnormal condition occurring on energized electrical equipment creating an arcing fault and arc flash incident. The long-anticipated update to the IEEE 1584 Guide for Performing Arc-Flash Hazard Calculations finally published November 30, 2018. Author: Terry Becker, P.Eng., CESCP, IEEE Senior Member ![]()
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