Patent ID: 11967470
Assignee: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. A contactor, comprising:
a stator comprising a core and windings;
an armature that moves relative to the stator;
fixed contacts that are fixed in position relative to the stator;
movable contacts that move with said armature relative to the stator and that are movable relative to said armature; and
a contact thickness change determination system comprising an electronic controller and a position sensor for sensing a position of the armature relative to the stator and providing armature position data to the electronic controller that indicates the position of the armature, wherein said electronic controller is adapted to:
use said armature position data to determine a first displacement distance moved by the armature from a reference location to a first transition point during a switch-off operation of the contactor at a first contactor life reference time when the movable contacts and the fixed contacts of the contactor define a first contact thickness;
use said armature position data to determine a second displacement distance moved by the armature from the reference location to a second transition point during a switch-off operation of the contactor at a second contactor life reference time after said first contactor life reference time when said movable contacts and said fixed contacts define a second contact thickness that is less than said first contact thickness; and
use said first displacement distance and said second displacement distance to determine a contact thickness change between said first contact thickness and said second contact thickness.