Reliable lamp life timer
US6373201B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2000 |
| Grant date | Apr 16, 2002 |
| Priority date | — |
| Expiry date | Dec 21, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for controlling a lamp. A timer (106) reads a rated safe life value from a memory (102) associated with a lamp in a lamp module (104). The memory (102) in the lamp module (104) contains a series of locations in which the rated safe life of the lamp has been stored, and a series of locations for storing the elapsed on time of the lamp. The timer controller (106) reads the series of locations storing the rated safe life of the lamp and verifies the validity of the values using a series of checksums and comparisons between the various values. The timer controller (106) also reads the series of locations storing the elapsed on time for the lamp and verifies the elapsed on time in a similar manner. If either the rated safe on time or the elapsed on time cannot be verified, the lamp is disabled. If both can be verified, and the lamp is enabled until the elapsed on time equals or exceeds the rated safe life.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.