Filter capacitor precharge apparatus
US5142435A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 1990 |
| Grant date | Aug 25, 1992 |
| Priority date | — |
| Expiry date | Jun 4, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H47/22
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus is provided for precharging a filter capacitor to prevent damage to a set of contacts resulting from arcing across the contacts. Included is a coil, a set of contacts, and a battery, such that the contacts and filter capacitor are connected in series and the series connected combination is connected in parallel across the battery. Also included is a switch, and a microprocessor for producing a triggering signal responsive to the closure of the switch. A driving circuit receives the triggering signal and responsively produces a charging signal. A charging circuit receives the charging signal and responsively charges the filter capacitor. Thereafter, the microprocessor produces an energizing signal causing the coil to become energized and the contacts to responsively close. By precharging the filter capacitor before the closure of the contacts, the voltage potential across the contacts is reduced. Therefore, no damage occurs due to arcing across the contacts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.