Arc Flash Study

Arc flash and electrical shock are the primary safety hazards for personnel working near exposed, energized electrical conductors or equipment.
ETAP Arc Flash Hazard Analysis software is used to perform arc flash analysis for systems from 0.208 kV to 15 kV in accordance with IEEE 1584-2018 “IEEE Guide for Performing Arc Flash Hazard Calculations & NFPA 70E 2018 - Standard for Electrical safety in the Workplace.

The objective of the Arc Flash Study is to provide information that allows plant staff to take appropriate precautions when working on energized electrical equipment to reduce the potential risk of injury from an arc flash event. The Arc Flash Study builds upon the results of the Short Circuit and Protective Device Coordination Studies to calculate the incident energy, PPE Level, and arc flash boundary for each piece of equipment in the electrical distribution system in accordance with based upon NFPA 70E 2018 Edition and IEEE 1584-2018. Results of this study are printed on labels and attached to electrical equipment to inform plant staff of shock hazards and arc flash hazards associated with working on energized equipment.

• Bolted Fault Current – Ibf” (kA)
• Arcing Current – Ia” (kA)
• Incident Energy – IE (cal/cm2)
• FCT- Fault Clearing Time (sec)
• Arc Flash Boundary – AFB (metres)
• Safe Working Distance – Dw (cm)
• Energy Levels & PPE Requirements

Arc Flash occurs during a fault or short circuit which passes through the air gap. Arc flash event can release large amount of energy in the form of light and heat .Arc flash study or Arc flash analysis gives the incident energy at various switchgear levels. The incident energy at various switchgears can change with respect to its voltage level, fault level, protection settings, and bus bar arrangement. By properly calculating incident energy at a point the shock and arc flash boundaries can be arrived at. A short circuit study and protection co-ordination study must be performed before Arc Flash Study.

After performing the Arc flash study, arc flash labels will be printed. Arc flash label shows the arc flash boundary, minimum arc rating of the protective clothing etc. While working inside the arc flash boundary which is obtained from the arc flash study the workers should wear proper Personal Protective Equipments (PPE) and arc flash rated clothing.

The major objective of arc flash study and arc flash labels to provide arc flash boundary and PPE rating to improve the safety of the personals working in the live network. Energy released in the form of heat, sound waves and light due to arc flash event have the potential to cause injuries and threat to life. Arc flash study helps to choose the class and rating of the Personal protective equipments.