Towards the control of contact bounce

This paper presents studies into the reduction of electrical contact bounce for both a commercial contactor and a contactor model from a new approach. The new approach is based on the reduction of the kinetic energy of the moving contact. This is achieved by controlling the strength of the field flux by timing coil energization periods. A set of data is obtained from the measurement of contact bounces for a current of 10 A dc and an operating voltage of 40 V for conditions with and without the control circuit. The results show that bounce duration and the number of bounces in the latter case are 2-3x greater. Scanning electron microscope (SEM) photographs of the anode and cathode electrodes show, with an uncontrolled coil, contacts that suffer higher are erosion losses.