METHOD AND CONTROL DEVICE FOR SWITCHING A CONTACTOR

A method (30) for switching a contactor (1) is provided. The method (30) is performed by a control device (20) controlling a control voltage supplied to a coil (10) of the contactor (1), wherein the coil (10) is energized and de-energized to control the switching of the contactor (1). The method(30) comprises obtaining a delay time deltaT from a predetermined set of N values, wherein the obtaineddelay time deltaT is different than the preceding selected delay time deltaT, determining (31) a reference point of time, t1, based on the obtained delay time, deltaT, wherein a starting point, to, ofthe delay time deltaT is set in relation to a start-up of the method (30), estimating (32) a half period, Tp, of the control voltage, determining (33) a duration of a measuring interval, Tm, based onthe estimated half period Tp of the control voltage, setting (34) starting point of a first measuring interval Tm based on the reference point of time t1, and setting starting points of subsequent measuring intervals equal to