What arc flash calculations does CAPE provide?
CAPE’s Arc Flash macros in the System Simulator module determine the worst product of fault current “I” and fault clearing time “t.” CAPE computes the clearing time based on the response of the protective devices around the fault location, which is basically a stepped-event analysis. Thus, a fault might need multiple breaker openings before it is actually cleared. In a radial system, there is probably only one device that will operate to clear the fault. But in a network, multiple breaker openings might be needed. The CAPE macros apply a user-specified fault at a large number of locations in the network: at buses, sliding faults on lines to determine the clearing time. For each network component, the largest I x t product is determined to be the worst-case arcing scenario. The macros output this information into a text file. You can use this text file output to calculate the incident energy and the arc flash boundary outside of CAPE. However, we have been hearing from other CAPE users
