Solid-state trip device comprising an instantaneous tripping circuit independent from the supply voltage
US4914541A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1989 |
| Grant date | Apr 3, 1990 |
| Priority date | — |
| Expiry date | Jan 27, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H1/063
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a system-powered solid-state trip device, the measurement voltage Vm, representative of the current flowing in the conductor to be protected and applied to the input of an electronic processing unit, can also be applied to the cathode of a thyristor connected in series with the trip coil and receiving on its gate, the tripping orders from the processing unit. A Zener diode is connected between the thyristor gate and the ground so as to set an instantaneous tripping pick-up of the trip device. In this way, a short-circuit in the conductor causes instantaneous tripping of the circuit breaker independently from the value of the supply voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.