Electrical ground fault detection apparatus
US6081122A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 9, 1995 |
| Grant date | Jun 27, 2000 |
| Priority date | — |
| Expiry date | Jun 9, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A ground detection apparatus for sensing the presence of a malfunction within an electronic instrument. The apparatus includes an active electrical circuit for delivering electrical energy from a power source to an electrically-driven instrument. The apparatus further includes a plurality of return electrical circuits connected in series with the active electrical circuit distal the electrically-driven instrument. A transformer coil is positioned within the apparatus such that the active electrical circuit includes a first winding about the transformer coil and such that one of the return electrical circuits includes a second winding about the transformer coil. The first and second windings are configured such that no substantial net flux is created in transformer coil when the plurality of return electrical circuits are functioning properly. The apparatus further includes a sensing and signalling circuit capable of sensing the presence of a flux in the transformer coil and producing a signal in response thereto. The circuit which the signal triggers has the capacity to deactivate the power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.