Experimental study of reignition evaluators in low voltage switching devices

The re-ignition of the arc during the interruption process deteriorates the switching performance of low voltage switching devices (LVSDs). Avoiding re-ignition is thus a key goal in the effective design of the quenching chamber. A reliable evaluator of re-ignition provides the opportunity to predict the switching performance of a LVSD during the design process and to refine the product prior to manufacture and empirical device testing. In this paper, re-ignition evaluators are investigated through the analysis of interruption test data for several types of LVSDs under the single-phase and three-phase circuit conditions. It is observed that the ratio of the recovery voltage to exit arc voltage, where exit arc voltage is defined as the value of the arc voltage immediately prior to the current zero point, is a reliable evaluator for the prediction of re-ignition in the switching tests of LVSDs. It is also noted that there are no occurrences of instantaneous re-ignition where this voltage ratio lies in the range of 1.0 to -1.0 and there is a threshold of the voltage ratio at approximately -2.0, which can distinguish the successful interruption and instantaneous re-ignition