IEEE
IEEE 1584
Guide for Performing Arc-Flash Hazard Calculations
The calculation method for arcing current, incident energy and the arc flash boundary at a given point in a system, and therefore the source of the numbers on an arc flash label. The result depends on available fault current and on protection clearing time, which is why an arc flash study has an integrity shelf life: any change to the supply, the transformer, the cable or a relay setting invalidates it. The 2018 edition changed the model substantially, so an older study is not simply conservative.
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