Improvement in Consistency and Overall Yield of Magnetic and Thermal Performance in New Range of MCCB of Lower Rating (16 A – 100 A) with FTFM

Abstract

Circuit breakers are the switchgear devices which are used for different electrical applications. MCCB is one of the switchgear devices having the current carrying capacity from 16A to 1600A with breaking capacity from 25kA to 250 kA. The main aim of this project is Magnetic and thermal yield as well as consistency improvement of new range of MCCB with FTFM. This MCCB will be used for the lower rating applications having thermal and magnetic release (TMR) which provides the protection against the overload condition and short circuit fault condition with rated breaking and making capacity. The overall performance of the MCCB is better but the issues consist in the magnetic and thermal release on production line. The project demonstrates the improvement in yield and consistency of the MCCB. The work involves the improvement by using the tools DFMEA, DOE, DMAIC, 6 SIGMA and FISH BONE DIAGRAM.