Multifunction integrated low voltage apparatus

A novel multifunction integrated low voltage apparatus is presented in this paper. Although its appearance looks a contactor, its contact and arcing chamber is innovated and power electronic technology is tied with its electromagnetic system so as to improve effectively the apparatus´s making and breaking current capability, furthermore, microcontroller is imbedded in the apparatus as its measure and control core. As a result, it is provided with several apparatus´s functions including contractor, circuit breaker, thermal relay and so on. The static characteristics and dynamical characteristics of the electromagnetic system is computed and analyzed based on finite element method by means of the ANASY software in this paper, the influence of counterforce, coil diameter and number of windings for the breaking velocity and resetting time during switch-off is studied. And the prototypes have been tested and put to use, the results show a good agreement with the predictions.