Load switching arrangement for gas discharge lamp circuit
US4558262A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 1983 |
| Grant date | Dec 10, 1985 |
| Priority date | — |
| Expiry date | Mar 9, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/386
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Individual banks of gas discharge lamps are provided with a common dimming control system. If a bank of lights is turned on while others are on and in a dimmed condition, the voltage applied to all lamps is increased over a relatively short period of time to full voltage to ensure the proper striking of the new bank of lamps but over a sufficiently long time period that users of the dimmed banks of lamps will not be noticeably affected by the change in lamp output. Full power is then maintained for a sufficiently long time to ensure proper lamp striking and stabilization and all banks are then very gradually returned to the original dimmed illumination condition which was set before the new lamp bank was energized. A long time delay and a short time delay are applied to respective inputs of a comparator to enable the initiation of the lamp striking sequence for the new lamp bank and prevents the initiation of the lamp striking sequence due to short time disturbances on the line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.