GFCI ground fault current filtering
US6097580A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 1, 1999 |
| Grant date | Aug 1, 2000 |
| Priority date | — |
| Expiry date | Mar 1, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H1/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system for controlling the response of a ground fault circuit interrupter in the presence of random leakage currents due to the presence of a conductive media such as water or ice. The signal from a magnetic core differential transformer is applied to two filters in parallel. The first filter passes the fundamental frequency of the source and the second filter passes a broad band of frequencies starting at twice the fundamental frequency. The output of the filters are applied to a microprocessor which manipulates the filter outputs and compares certain of the filter outputs to a stored pattern of expected current leakage. The microprocessor operates a relay to disconnect the load from the source when a fault condition exists.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.