On Novel Methods for Characterizing the Arc/Contact Movement and Its Relation With the Current/Voltage in Low-Voltage Circuit Breaker

This paper presents a work that was aimed to develop methods along with test facilities for characterizing the arc/contact movement in low-voltage miniature circuit breaker which has a related current under 125 A, and to find its relation with the short-circuit current/voltage in the circuit. The method consists of: 1) the high-speed camera for obtaining the image of the arc or contact movement; 2) the data acquisition system that measures the current during the short-circuit break; and 3) the circuitry system that establishes the synchronization of the arc movement capturing and the current acquisition. In particular, two methods were developed for this purpose: one based on analog signal and the other based on digital signal. The experiment shows that the accuracy of the synchronization, dependent on the sampling rate of the high-speed camera, is about from tens of microseconds to hundreds of microseconds with both methods. The two methods have their own advantages and disadvantages, and they can be tailored to applications for the best performance.