Miniature Circuit Breaker Electrical Energy Loss Test And Analysis Methods

The measuring and testing technique of the voltage data, current data and energy loss data about contact, bimetallic strip and electromagnetic tripping device of the miniature circuit breaker(MCB) are important in analyzing the factors influencing the working performance of MCB. This paper mainly studies on building an test equipment for MCB and collecting data, then analyze the energy loss of electromagnetic release, bimetal mechanism, and contact in the process of breaking.The hardware consists of current generating circuit, data acquisition circuit and a detection circuit. In the current generation circuit, each load resistor is connected to the output side of a solid state relay, and in parallel across the power supply AC. The current generating circuit can be determined by the number of solid-state relays control switched to produce the desired current. Detection circuit is composed of sensors and data acquisition card composition. Voltage sensors are used to measure the voltage of the contact, bimetal, electromagnetic release voltage. In order to improve the accuracy of the data, two sensors are used to measure the voltage of contacts. Current sensors are used to measure the current of the trunk circuits.Software of the test device which consists of control procedures, data collection procedures, filtering procedures and data processing procedures is designed by LabVIEW. The control program produces the desired current through the hardware circuit operation. Filtering procedure elliptical filtering method is used to remove the interference signal acquisition in the white noise. The data processing part, including the collected data processing, real-time calculation of instantaneous energy loss during the mini-break circuit breaker bimetal, electromagnetic release, contact the three parts, is processed to obtain the delay time, the arcing time and other parametersFinally, analyze the energy distribution in the whole process of breaking based on the data about collection of MCB connected with the breaker status contact, bimetallic strip and electromagnetic trip.