Changeability of arc flash parameters and its impact on hazard mitigation in low voltage power systems

Arc flashes in power system result in a huge amount of incident energy that can injure human workers. Strict safety measures have to be applied in the work place for safety of technical personnel. Computation of the incident energy is imperative to determine the corresponding safety requirements. Arcing current, and hence incident energy, is a function of some system parameters which may vary due to different reasons. This research work considers the problem of parameter variability in arc flash calculations and its effect on hazard mitigation. A mathematical basis is set forth for the impact of the variation in gap between electrodes and system voltage on the incident energy value. Findings of this work emphasize that small variations in system parameters can yield inaccurate values of incident energy and misleading hazard categories. Therefore, parameter variation has to be carefully accommodated in the arc flash calculations to result in the proper hazard mitigation precautions.