Improvement in Short Circuit Performance of 100 A/250 A Frame MCCB

Abstract

Moulded Case Circuit Breakers (MCCB) are widely used for Protec- tion against Overload current and Short circuit faults in LT lines. Im- provement in short circuit performance of MCCB helps in reducing let through energy during short circuit fault clearance. Therefore it reduces electrical stresses on SCPD, application and connecting cables in the event of short circuit fault. Critical parameters such as erosion pattern of contact buttons, arcing intervals, construction of arcing chamber, speed of contacts separation and material properties will be analyzed for selection of the best concept. Selection of the best concept will be based on the theoretical calculations, simulation results and validation testing results of prototypes samples.