Quality Improvement in Under Voltage Release

Abstract

Moulded Case Circuit breaker(MCCB) is safety device that generally protect the system against overloading and short-circuit conditions. However, in certain application it is necessary to protect system against under voltage condition. To add on the protection against under voltage, an additional accessory called Under Voltage Release (UVR) is installed in MCCB. UVR trips the circuit breaker during under voltage condition. The quality, accuracy and reliability of UVR is essentially to be controlled for the smooth functioning of MCCB. The project focus on improvement of quality of UVR and reduce the probability of rejection. Various quality tools like Six sigma, gemba analysis, Design of Experiment, Why-Why analysis, 7 basic Qc tools etc. are used to study the existing production line of UVR and the effective solution are proposed to increase first time Yield of UVR.