Investigation of making process and associated contact bounce behaviors for alternating current contactor

The making process of alternating current (AC) contactor relates closely to the excited coil current and contact bounce behaviors. The reduction of pick-up time is beneficial for switching response of the electrical circuit. In this paper, a model switch which could adjust magnetic gap and contact gap of AC contactor is introduced. With the help of recorded coil current and contact voltage waveforms, the whole making process of contactor is divided into actuation, free acceleration, contact bounce, iron core bounce, and stable contact stages. The effect of coil resistance and contact gap on the pick-up time is investigated explicitly. The relationship between pick-up time and contact bounce duration, and associated influencing factors are analyzed.