Relevance of the power and zero factors on arc flash A.C.

This paper introduces a simplified calculation of the arc fault current as an update of the method, previously proposed by the authors, as a complement to the IEEE 1584-2018 guideline method, for calculating the incident energy and arc flash limit. The approximate calculation proposed introduces factors and equations that lead to results that are completely comparable with those obtained with the IEEE 1584-2018 guide, therefore confirming its validity. The supplementary contribution offered by the proposed method is to allow a physical understanding of the phenomenon thanks to the sensitivity analysis through the factors introduced relating to the effective value of the bolted short-circuit current, the nominal voltage of the electrical system, the configuration and the distance of the electrodes. This work deals in particular with the relevance of the power factor of the bolted short-circuit current in the characterization of the arc fault current, allowing the evaluation of the arc current, the resistance and arc voltage. Then, the proposed method evaluates the power factor of the arc fault current and introduces the zero-crossing factor of the arc fault current as a complement to the power factor, which facilitates the understanding of the behavior, continuous or pulsating, of the same arc fault current.