MULTI-ZONE CLOSED LOOP DAYLIGHT HARVESTING HAVING AT LEAST ONE LIGHT SENSOR

• US 20090212708A1
• Filed: 04/29/2009
• Published: 08/27/2009
• Est. Priority Date: 05/05/2005
• Status: Active Grant

• Current Assignee: Leviton Manufacturing Company Incorporated
• Original Assignee: Leviton Manufacturing Company Incorporated
• Inventors: Hick, Robert L., Leinen, Richard A.
• Granted Patent: US 8,110,994 B2
• Time in Patent Office: Days
• US Class Current: 315/152
• CPC Class Codes: H05B 39/042 by measuring the incident light
• CPC Class Codes: H05B 41/3922 and measurement of the incident light
• CPC Class Codes: H05B 47/175 by remote control

Abstract

A multi-zone daylight harvesting method and apparatus having a closed loop system utilizing a single light sensor is disclosed herein. This light control system includes an ambient light sensor connected to a detection circuit for detecting the amount of ambient light within a given zone and converting the light signal to an digital one. A control device couples to receive a predetermined rate of change for each respective zone from a storage unit along with the converted digital signal. The control device connects each zone of a plurality of electrical loads to control the power supplied to the electrical load at the predetermined corresponding rate of change and responsive to the amount of ambient light detected.

Claims

1. A method for controlling the brightness of a plurality of electrical loads comprising:

generating a first signal in response to sensing an ambient light level;

generating a second signal in response to detecting the first signal; and

controlling the plurality of electrical loads in response to the second signal;

wherein the plurality of electrical loads includes at least two zones, each of the at least two zones having a different corresponding predetermined rate of change for adjusting the brightness of the corresponding zone of the plurality of the electrical loads responsive to the ambient light level.

2. A method according to claim 1, wherein the at least two zones includes a first zone, a second zone and a third zone, the first zone having a first predetermine rate of change, the second zone having a second predetermined rate of change, and a third zone having a third predetermined rate of change.

3. A method comprising:

storing a first rate of change and a second rate of change, wherein the first and second rates of change are different;

detecting ambient light; and

controlling a first light source in a first zone and a second light source in a second zone in response to the ambient light;

wherein the brightness of the first light source in the first zone is changed at the first rate of change in response to a change in the ambient light; and

wherein the brightness of the second light source in the second zone is changed at the second rate of change in response to the change in ambient light.

4. A method according to claim 3 wherein the first rate of change is proportional to the change in the ambient light.

5. A method according to claim 4 wherein the first and second rates of change are proportional to the change in the ambient light.

6. A method according to claim 4 wherein the first and second rates of change are accessed by software.

7. A method according to claim 3 wherein the first and second rates of change are stored with an electromechanical device.

8. A method according to claim 7 wherein the electromechanical device comprises one or more potentiometers.

9. A method according to claim 3 wherein detecting ambient light comprises sensing light only from an exterior source.

10. A method according to claim 3 wherein detecting ambient light comprises sensing light from an exterior source and the first light source.

11. A method according to claim 3 wherein detecting ambient light comprises sensing light from an exterior source, the first light source, and the second light source.

12. A method for controlling the brightness of electrical loads, each electrical load belonging to one of a plurality of zones, the method comprising:

receiving a light detection signal;

adjusting the power supplied to a first electrical load in a first one of the plurality of zones at a first rate of change relative to the light detection signal, and

adjusting the power supplied to a second electrical load in a second one of the plurality of zones at a second rate of change relative to the light detection signal.

13. A method for adjusting a plurality of electrical loads in a plurality of zones, comprising:

determining an ambient light level near the plurality of electrical loads with a light sensor; and

adjusting the light output in each zone at a different predetermined rate of change for each zone responsive to the ambient light level determined by the light sensor.

14. A method according to claim 13, wherein the plurality of zones includes a first zone, a second zone and a third zone, and wherein the first zone has a first pre-determine rate of change, the second zone has a second predetermined rate of change, and a third zone has a third predetermined rate of change.

17. A method according to claim 13 wherein the light sensor is located in one of the plurality of zones.

15. A method according to 13 wherein:

the plurality of zones are located in a space that receives light from an external source; and

the zones receive unequal amounts of light from the external source.

16. A method according to claim 15 wherein the light from the external source comprises sunlight.