In or relating to circuit interruption devices
US11011335B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2015 |
| Grant date | May 18, 2021 |
| Priority date | — |
| Expiry date | Dec 10, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2071/044
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A trip apparatus for a circuit interruption device that comprises a coil operatively connectable to a circuit interruption device. The coil is configured to selectively operate the circuit interruption device to interrupt when a current flowing through the circuit interruption device exceeds a threshold. The trip apparatus also includes a current measuring device configured to selectively measure a coil current flowing through the coil to determine a measured coil current signal. In addition, the trip apparatus includes a monitoring device configured to determine the derivative of the measured coil current signal and to perform a correlation of the derivative of the measured coil current signal and a reference derivative of a reference coil current signal to determine a correlation output. The monitoring device is further configured to compare the correlation output with a reference correlation threshold to determine whether an operating condition of the coil is normal or abnormal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.