The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 19, 2002
Filed:
Jul. 30, 1998
Method of establishing the residual useful life of contacts in switchgear and associated arrangement
Fritz Pohl, Hemhofen, DE;
Norbert Elsner, Bubenreuth, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
To determine the remaining lifetime of contactor contacts, the contact spring action at the clearance gap can be determined as a substitute criterion for contact erosion, and to determine the erosion of the contact points, the change in spring action during the shutdown cycle can be measured and converted to the remaining lifetime, for which purpose, the time of the armature movement from the start of the armature movement to the start of contact opening is measured with the solenoid actuator having an armature with solenoids and associated yoke. The measured values of the time signal t of contact opening on the load side of the switching device monitored and the time signal t are determined by voltageless signaling of the start of armature movement. In particular for use in three-phase systems, the switching voltage is measured as a voltage change at an artificial neutral point. In the respective arrangement, a voltageless signal line is provided between the switching device and analyzer unit.