Circuit breaker comprising an electronic trip device
US5115371A · kind A · utility
96Cited by
5References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 5, 1990 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Sep 5, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/0935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The circuit breaker comprises a thermistor located in a cold zone, near the front face of the trip device and at least one thermistor located in a hot zone, at the bottom of the circuit breaker case, in proximity to the circuit breaker connection terminals. The temperature difference measured between the hot and cold zones is representative of the temperature rise of the system protected by the circuit breaker and is used to modify the time delay of a delayed tripping function when the circuit breaker closes. The trip device can also take into account the temperature difference existing at the time of the previous trip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.