Overcurrent protection device and arrangement
US5737161A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 25, 1996 |
| Grant date | Apr 7, 1998 |
| Priority date | — |
| Expiry date | Nov 25, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H71/26
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Overcurrent protection arrangements including a relay comprising two coils wound on a common magnetic core and a PTC device coupled in parallel with the relay contacts. The arrangement comprises a circuit interruption element which has a normal state which permits the flow of a normal circuit current, I.sub.NORMAL, to pass through the system, and a fault state which permits the flow of at most a reduced current, I.sub.REDUCED, substantially less than I.sub.NORMAL. A first control element is coupled in series between the power supply and the load, and is functionally linked to the circuit interruption element so that when the current through the first control element increases from I.sub.NORMAL to a relatively high current, I.sub.FAULT, the first control element can convert the circuit interruption element into the fault state. A second control element is coupled in parallel with the circuit interruption element, and is functionally linked to the circuit interruption element so that if the circuit interruption element is converted to the fault state, the second control element can cause the circuit interruption element to remain in the fault state as long as the current through the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.