Short-circuit ratings and application guidelines for molded-case circuit breakers

A working group representing the Petroleum and Chemical Industry Committee (PCIC) and the Low-Voltage Protection Subcommittee of the IEEE Industry Applications Society, including both users and electrical equipment manufacturers, is preparing a guide to give users information for the correct selection and application of molded-case circuit breakers (MCCBs) under short-circuit conditions. This paper is intended to be a tutorial presentation that attempts to resolve issues that have been raised in a number of IEEE papers. This is phase one of a series of papers and tutorials relating to the selection and application of MCCBs.