Patent · US Expired

Method of establishing the residual useful life of contacts in switchgear and associated arrangement

US6225807A · kind A · utility

12Cited by
7References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 3, 1998
Grant dateMay 1, 2001
Priority date
Expiry dateMar 3, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2071/044
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

To determine the remaining lifetime of contactor contacts, the contact spring action at the gap is determined as a substitute criterion for contact erosion, and to determine the erosion of the contacts, the change in spring action during a shutdown cycle is measured and converted to remaining lifetime. With a yoke and armature solenoid actuator with a solenoid, the armature path from the start of the armature movement to the start of contact opening must be measured. The time of separation of the armature from the yoke of the contactor solenoid actuator is determined from the voltage on the solenoid. The increase in magnetic resistance of the magnetic circuit when the magnetic armature is raised is determined. In the respective arrangement with an analyzing unit for determination and display of the remaining lifetime, the analyzing unit has means for detecting and measuring the voltage on the solenoid.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.