Ground fault indicating device
US5083114A · kind A · utility
4Cited by
2References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 27, 1990 |
| Grant date | Jan 21, 1992 |
| Priority date | — |
| Expiry date | Sep 27, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current transformer detects a ground fault current and outputs a secondary current signal to heat a filament disposed in an airtight flash lamp upon the occurrence of a ground fault. With heating of the filament, an ignition material is ignited in the lamp and causes weakening of the glass bulb of the lamp. A moving member pressing against the lamp shatters the weakened lamp and is displaced, thus releasing an indicator to project from a holder to a ground fault indicating position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.