Indication of solenoid temperature change

摘要

A method of indicating a temperature change of a solenoid driving a movable part of an actuator is disclosed. In applying the method a supply provided to the solenoid is sensed. Further, a chopping characteristic of the sensed supply is determined during a time period wherein a current supply is chopped between a first predetermined value and a second predetermined value. In addition, a chopping characteristic variation over time is detected and an indication signal is generated in dependence of a detected chopping characteristic variation exceeding a predetermined threshold.