Electronic trip device comprising a capacitor for supply of a trip coil
US6842322B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 25, 2002 |
| Grant date | Jan 11, 2005 |
| Priority date | — |
| Expiry date | Dec 27, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H1/066
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The trip device comprises a system-powered power supply circuit comprising a capacitor for power supply of a trip coil. When the trip device is powered on, the capacitor charges and its voltage is regulated according to a first reference voltage sufficient to activate the trip coil if necessary. After a preset period, regulation of the voltage at the terminals of the capacitor is performed according to a second reference voltage, lower than the first voltage. The reference voltage reverts to the first value during the same preset period when the measured current reaches a preset threshold, which constitutes an indication of the presence of a fault that will lead to tripping being required. The capacitor is therefore generally charged at a lower voltage than that which is necessary for tripping, thus enabling its size to be reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.