Patent · US Expired

Emergency lighting test system and method

US6285132A · kind A · utility

17Cited by
8References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 21, 2000
Grant dateSep 4, 2001
Priority date
Expiry dateApr 21, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An emergency lighting test system and method automatically schedules self tests and uses novel test methods to thoroughly test an emergency lighting system. An emergency lighting system comprises a fluorescent lamp, an inverter circuit and a backup power source (e.g. a battery). A microcontroller controls testing of the system and tracks time of day and date for scheduling tests of the lighting system. After a test is performed, the test reports are stored in memory. Two novel tests are used to evaluate the lighting system. A first test determines backup power source condition. The test samples the high frequency signal generated by the inverter circuit to determine an average peak voltage. The average peak voltage is indicative of backup power source voltage. If the average peak voltage falls below a predetermined lower limit, it indicates a backup power source failure. The lamp is turned off and a failure is flagged. A second test determines lamp and inverter condition. This test measures the frequency of the high frequency signal generated by the inverter circuit. The high frequency signal is filtered and divided down to a convenient frequency suitable for interfacing with the m…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.