Could the new high interrupting capacity circuit breaker change your distribution system?

The authors describe characteristics and applications for high-interrupting-capacity molded-case circuit breakers and motor circuit protectors that allow the use of large secondary unit substation transformers. Generalized system data are presented, allowing most system selections without detailed calculation. Test data results are noted that provide series ratings of these circuit breakers when applied as upstream devices, or for various lesser-rated downstream devices, such as might be found of a feeder breaker serving distribution panelboards or packaged equipment.<>