Overcurrent protection circuits comprising combinations of PTC devices and switches
US5864458A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1995 |
| Grant date | Jan 26, 1999 |
| Priority date | — |
| Expiry date | Nov 29, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/334
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Electrical circuit protection arrangements with PTC devices and mechanical switches. The combinations of this invention permit the use of mechanical switches and PTC devices to switch voltages and currents in normal circuit operations, wherein the voltage and/or current ratings of the mechanical switches and PTC devices are much less than the normal operating voltages and currents of the circuits. This feature permits the use of smaller and less expensive mechanical switches and PTC device than would otherwise be required in such circuits. The arrangements of switches and PTC devices also permit the PTC devices to limit the magnitude of the fault current passed to the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.