Mechanical Analysis of Power Electromagnetic Contactors

AbstractThis paper presents an analysis of the drive mechanism of an AC three-phase electromagnetic contactor. One of the key-feature of the drive mechanism is the strength characteristic, which has been established from experimental tests. A good correlation between strength torque characteristic and the mechanical characteristics of the drive coil for different voltage supply (from 1.1 to 0.7 of rated voltage) has been observed. The recorded oscillograms of the time evolution of the trip of the movable armature, allow to obtain the connection time and the disconnection time of the contactor. Also, the drive coil has been supplied with variable voltage (from 1.1 to 0.7 of rated voltage). The connection and disconnection times are important parameters related to the contactor behaviour from mechanical point of view