Electric character analysis of low-voltage switchgear and design of test system

The test of low-voltage switchgear (contactor, relay, breaker etc.) includes electric longevity and electric characters of turn on-off. The fast calculation and analysis methods for electric parameters were investigated. Much attention has been paid to the effect of performance in low-voltage switchgear caused by arcing time, over-voltage of contact, power factor and harmonic. On the base of studying character of test, such as more measured signals, severity of disturbance from strong electromagnetism, shorter interval and vast data in test, an efficient testing system has been designed with the function of data acquisition and processing. This system possesses six channels of voltage signal and three channels of current signal. The frequency of data collecting in every channel is 1 MS/s and the isolation voltage exceeds 2500 V. The results show that all requirements in test have been implemented wholly.