Patent · US Expired

Method of determining contact wear in a trip unit

US6466023B2 · kind B2 · utility

15Cited by
12References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 7, 2001
Grant dateOct 15, 2002
Priority date
Expiry dateMar 10, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2011/0068
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A method of determining contact wear in a trip unit of a circuit breaker and a circuit breaker employing such a method are presented. The trip unit includes a microcontroller and associated memories. An algorithm (program) stored in a memory of the trip unit calculates cumulative energy dissipated in the breaker contacts using the current signal detected at the time of separation. Measurement of cumulative energy dissipated in the breaker contacts is proportional to contact wear. Maintenance setpoints are determined based on industry standard endurance tests and alarm threshold and trip thresholds further based on industry standards are provided within the algorithm for notifying local or remote personnel of a necessary maintenance procedure.

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