The big picture of arc-flash mitigation

This paper provides a big picture of arc-flash mitigation. From pre-arc issues, both preventive measures as well as various arc fault prediction technologies are discussed. Arc fault prediction is explained as identifying a developing arc fault by analyzing pre-arc conditions, in practice by on-line monitoring. Because preventive or predictive measures can not totally eliminate the risk of arc faults, arc fault mitigation is justified. Two mitigation approaches, current-limiting and time-limiting, are discussed, and the risks related to current limitation are illustrated. Performance of light and overcurrent detection based mitigation is presented, and aspects of arc elimination by either circuit breaker or by an arc eliminator are discussed.