Pre-insertion inductor arrangement
US4695918A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 24, 1986 |
| Grant date | Sep 22, 1987 |
| Priority date | — |
| Expiry date | Jul 24, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H33/16
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A pre-insertion inductor arrangement is provided for a circuit interrupting device or high voltage switch to reduce audible and electrical noise and to limit transient inrush current and/or voltages upon closing of the circuit by the circuit interrupting device or high voltage switch. The arrangement provides the insertion of the inductor for a plurality of cycles of the source frequency and thus does not require precise timing. The pre-insertion inductor does not require the use of a stack of resistor blocks or cakes of the prior art. Further, since the pre-insertion inductor has relatively low losses, the energy dissipation requirements of the pre-insertion inductor are significantly less than for pre-insertion resistors. Additionally, since the pre-insertion inductor is not continuously in the circuit, there is no requirement to carry continuous load or fault current or to accomodate losses on a continuous basis. Thus, an effective inductance for the pre-insertion inductor can be achieved in a desirable configuration having compact dimensions. In a specific embodiment, the pre-insertion inductor arrangement inserts the inductance between a switch blade and a switch contact durin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.