Patent ID: 8159807

Claim:
A method for operating a switching device using at least one electromagnetic drive, which includes a displaceable armature for opening and closing at least one main contact of the switching device, the method comprising: identifying a magnetic flux modification in a cylindrical opening formed between an excitation coil and a coil form of the electromagnetic drive by identifying a change in an outer permanent magnetic due to displacement of a movable armature within the cylindrical opening, the magnetic flux modification occurring due to a change between a first position with a switched-off main contact of the electromagnetic drive and a second position with a switched-on main contact of the electromagnetic drive; and restricting a solenoid current of the electromagnetic drive to a certain current value in the second position, when the magnetic flux modification exceeds a threshold value wherein an error message is output if, after the expiry of a period of time after switching on the solenoid current, a magnetic flux modification is not identified in the electromagnetic drive of the switching device.