Arc Flash Calculator

By R. W. Hurst, The Electricity Forum

Arc flash calculator software demonstrates arc flash hazard calculations and the impact that system changes have on energy levels and personal protective equipment Requirements (PPE) for Arc Flash Hazards. It is best designed to estimate incident energy levels and can also categorize arch flash hazards at any point in an electrical system. This special engineering software determines the fault clearing time for protective device (like electrical circuit breakers) settings. It can also calculate incident energy and flash protection boundaries (safe distance from an explosion); documents personal protective equipment (PPE) requirements; and prints custom warning labels, energized work permits, and diagrams with input data and calculation results. It also uses generous tolerances for utility, transformer, cable, and motor data to calculate conservative minimum and maximum fault currents. It includes a validated library of protective device trip characteristics to provide accurate trip times for the calculations.

Reducing the electrical energy delivered to the arc flash incident will reduce the amount of arc flash energy generated. This decrease in incident heat energy usually reduces the category of personal protective equipment (PPE) required, enabling personnel to work more easily and efficiently.

Software can be used to determine incident heat energy at a particular distance and the category of PPE required. Simply enter the bolted fault current, choose a current-limiting fuse from the drop-down menu, and select "calculate." See cautionary notes prior to use.

Calculations are based on three-phase tests at 600V using a 20" x 20" x 20" box, as described in IEEE 1584, Guide for Performing Arc Flash Calculations. They determine the PPE required to protect against the effects of radiated heat, and do not take into account the effects of pressure, molten metal droplets, toxic smoke or plasma jets. Actual arc flash results could be different from the results given here.

Software resources:

Arc Flash Hazard Calculator - IEEE 1584 Method

Arc Flash Hazard Calculator - Easy Power

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