Incident energy reduction techniques: A comparison using low-voltage power circuit breakers

The use of reduced arc-flash design circuit breakers can inherently limit the arc-flash incident energy within the circuit breaker´s protective zone. The amount of arc-flash reduction can be substantial. The low arc-flash circuit breaker is most effective in lowering arc-flash incident energies when the system parameters are within the range of its manufacturer-published incident energy equation applicability limits, and the circuit breaker is available for the application and ampacity required. Care must be taken to ensure that system selectivity is retained when using this type of circuit breaker, and in some situations acceptable selectivity may not be possible.