Fault trip indicator and maintenance method for a circuit breaker
US6774803B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 31, 2002 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | Jun 8, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H1/0015
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A fault trip indicator for use with a circuit breaker connected to protect an electrical line comprises a current transformer coupled to the electrical line to produce a current signal which varies as a function of the current level in the electrical line. A threshold detector is coupled to the current transformer to produce a load signal when the threshold detector detects that the current signal exceeds a threshold value. A monitoring circuit is coupled to the protective circuit in the circuit breaker and the threshold detector to provide an indication of the occurrence of the protective circuit opening the circuit breaker while the threshold detector is producing the load signal. A fault trip indicator using passive circuitry, a battery powered threshold detector and binary load signals are also disclosed. A counter for counting the number of fault trips and a display for displaying the count are also disclosed, as are an auxiliary current transformer coupled to the main current transformer in the circuit breaker to provide the current signal. A method of performing maintenance on a circuit breaker is also disclosed. Other embodiments and features are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.