Application of Incident Energy Reference Boundary Area Plots in TCCs Considering IEEE 1584-2018 Input Parameter Variability

A simplified arc-flash analysis technique that allows for the determination of the settings of overcurrent protective devices and selection of arc-rated personal protective equipment (PPE) based on a reference constant incident energy boundary area is presented in this article. The reference areas are created based on the equations of IEEE Standard 1584-2018 [1], taking into consideration potential variation in the input parameters described in the standard. The method presented in this article provides an efficient and straightforward means to simultaneously consider the effects of varying input parameters on arc-flash calculation results by plotting areas of constant incident energy on a time-current plot. Actual power distribution equipment may have multiple electrode configurations, gaps between conductors, operating voltages, as well as a range of available bolted short-circuit currents and variation in the size of equipment enclosures. The multiple combinations require dozens of simulations to determine the worst-case incident energy levels. Unlike previous implementations of incident energy curves, which were typically single line representations of the incident energy, the plotting of bounded areas (C-area plots) allows for multiple parameter sweeps to determine a band of variation within a defined set of parameter combinations.