Ground fault interrupter
US5539602A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 1994 |
| Grant date | Jul 23, 1996 |
| Priority date | — |
| Expiry date | Oct 19, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/32
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ground fault interrupter, operable in a measurement state, is employed with a DC circuit having a DC power source and a load. The DC source supplies DC current to the load along a supply current path and receives DC current from the load along a return current path. The ground fault interrupter comprises a first resistance in series with the supply current path, a second resistance in series with the return current path, and a current interrupter disposed in series with one of the current paths. The current interruptor interrupts the one of the current paths in response to actuation of the current interrupter. The ground fault interrupter further includes a measurement unit for measuring voltage drops across the respective first and second resistances during the measurement state, obtaining a measurement value using a difference between the voltage drops, and comparing the measurement value to a predetermined threshold. The measurement unit is constructed and arranged to actuate the current interrupter in response to the measurement value exceeding the predetermined threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.