Equipment and methods for emergency lighting that provides brownout detection and protection

• US 20060066258A1
• Filed: 09/28/2004
• Published: 03/30/2006
• Est. Priority Date: 09/28/2004
• Status: Active Grant

• Current Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Original Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Inventors: Lane, John Evan, Zulim, Don
• Granted Patent: US 7,256,556 B2
• Time in Patent Office: Days
• US Class Current: 315/291
• CPC Class Codes: H02J 9/065 for lighting purposes
• CPC Class Codes: H05B 41/28 using static converters
• CPC Class Codes: H05B 45/375 using buck topology

Abstract

The present invention relates to systems, equipment and methods that provide emergency lighting and allow the detection of brownout conditions. One aspect of the present invention is an emergency lighting system with an input voltage interface for receiving an input voltage, a brownout detection component for detecting a brownout condition on the input voltage and generating a brownout signal, a switch mode power converter for altering the input voltage; and an emergency lighting control and battery charging component for controlling the charging of a battery pack and receiving the brownout signal. Another aspect of the invention is a method of providing emergency lighting performed by receiving an input voltage; automatically establishing a brownout threshold relative to the input voltage; and detecting a brownout condition.

Claims

1. An emergency lighting system comprising:

an input voltage interface for receiving an input voltage;

a brownout detection component for detecting a brownout condition and generating a brownout signal;

a switch mode power converter for altering the input voltage; and

an emergency lighting control and battery charging component for controlling the charging of a battery pack and receiving the brownout signal.

2. The system of claim 1 wherein the input voltage interface further comprises:

an AC line voltage interface; and

a rectification and filtering circuit.

3. The system of claim 1 wherein the brownout detection component determines one or more brownout thresholds for one or more input voltages.

4. The system of claim 3 wherein one or more of the brownout thresholds are proportional to one or more of the input voltages.

5. The system of claim 3 wherein

the input voltage has an associated line frequency;

and

the brownout detection component determines one or more brownout thresholds independent of the line frequency.

6. The system of claim 1 wherein

the switch mode power converter has a primary and a secondary side;

and

the brownout detection component detects the input voltage on the primary side of the switch mode power converter.

7. The system of claim 1 wherein the brownout detection component communicates the brownout signal to the emergency lighting control and battery charging circuit.

8. The system of claim 7 wherein

the switch mode power converter has a primary and a secondary side;

the brownout detection component detects the input voltage on the primary side of the switch mode power converter; and

the brownout detection component is electrically isolated from the secondary side of the switch mode power converter.

9. The system of claim 1 further comprising one or more batteries.

10. The system of claim 1 further comprising a remote test interface component.

11. A method of providing emergency lighting comprising:

receiving an input voltage;

automatically establishing a brownout threshold for the input voltage; and

detecting a brownout condition.

12. The method of claim 11 further comprising transforming the input voltage using a switch mode power converter.

13. The method of claim 11 further comprising transforming the input voltage to charge a battery.

14. The method of claim 11 further comprising altering the input voltage to power an emergency lighting control component.

15. The method of claim 11 wherein the step of detecting a brownout condition is accomplished using the brownout threshold.

16. The method of claim 11 wherein the brownout threshold is proportional to the input voltage.

17. The method of claim 11 wherein the brownout threshold is determined independent of the frequency of the input voltage.

18. The method of claim 11 further comprising sending a brownout signal to activate a lighting device.

19. The method of claim 11 further comprising activating an isolated lighting device.

20. The method of claim 11 wherein the input voltage is in the range from 85 to 305 Volts.

21. A brownout protection system comprising:

an establish brownout threshold component for automatically determining a brownout threshold for an input voltage;

a monitor input voltage component for detecting a brownout condition when the input voltage drops below the brownout threshold;

a signal emergency lighting component to signal emergency lighting when a brownout condition is detected.

22. The system of claim 21 wherein the brownout threshold value is proportional to the input voltage.

23. The system of claim 21 wherein the signal component includes an opto-coupler.

24. A method of providing emergency lighting comprising:

receiving an input voltage;

monitoring the input voltage for a brownout condition;

if a brownout condition exists, sending a brownout signal to activate emergency lighting; and

if a brownout condition does not exist, using a switch mode power converter to provide power.

25. The method of claim 24 wherein the switch mode power converter provides power to charge a battery.

26. The method of claim 24 wherein the switch mode power converter supplies power to charge an emergency lighting control component.

27. An emergency lighting unit comprising:

a converter capable of receiving a wide range of input voltages; and

a brownout detection component capable of detecting a brownout condition based at least in part on an input voltage from the wide range of input voltages.

28. The system of claim 27 wherein the converter is a switch mode power converter.

29. The system of claim 27 wherein the converter operates over a range between 85 and 305 VAC.

30. The system of claim 27 wherein the converter does not have voltage specific taps.

31. The system of claim 27 wherein the converter accepts one or more odd voltage and frequency inputs.

32. The system of claim 27 wherein the brownout detection component determines one or more brownout thresholds.

33. The system of claim 32 wherein the brownout detection component determines the one or more brownout thresholds using the wide range of input voltages.

34. An emergency lighting unit comprising:

an input voltage interface for receiving a wide range of input voltages;

a converter for receiving an input voltage from among the wide range of input voltages and having a primary and a secondary side;

a brownout detection component for determining one or more brownout thresholds, monitoring the input voltage on the primary side of the converter, and generating a brownout signal; and

an emergency lighting control and battery charging component for controlling the charging of a battery pack and receiving the brownout signal on the secondary side of the converter.