Multi-modal load control system having occupancy sensing

• US 8,665,090 B2
• Filed: 01/13/2010
• Issued: 03/04/2014
• Est. Priority Date: 01/26/2009
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Bull, John H.
• Primary Examiner(s): Vo, Tuyet Thi
• Application Number:
  US12/686,634
• Publication Number:
  US 20100188009A1
• Time in Patent Office: 1,511 Days
• Field of Search: 340/539.26, 340/540, 340/541, 340/561, 340/565, 340/566, 340/567, 315/291, 315307-311, 315149-159
• US Class Current: 340/539.26
• CPC Class Codes: H02J 2310/14 The load or loads being home appliances
• CPC Class Codes: H02J 3/00 Circuit arrangements for ac mains or ac distribution networks
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• CPC Class Codes: H05B 39/081 by measuring the incident light H05B39/083 takes precedence
• CPC Class Codes: H05B 39/085 by touch control
• CPC Class Codes: H05B 47/115 by determining the presence or movement of objects or living beings
• CPC Class Codes: H05B 47/17 Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations
• CPC Class Codes: H05B 47/175 by remote control
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/246 the system involving the remote operation of lamps or lighting equipment

Abstract

A multi-modal load control system includes a sensor that operates as an occupancy sensor in a first mode of operation and operates as a vacancy sensor in a second mode of operation. The load control system comprises a load control circuit adapted to be coupled in series electrical connection between an AC power source and an electrical load for controlling the amount of power delivered to the load in response to sensor, which is operable to detect occupancy or vacancy conditions in a space in which the sensor is located. In the first mode of operation, the load control circuit turns the load on when the sensor detects the occupancy condition and turns the load off when the sensor detects the vacancy condition. In the second mode of operation, the load control circuit turns the load off when the sensor detects the vacancy condition and does not turn the load on when the sensor detects the occupancy condition.

Claims

1. A load control system for controlling the amount of power delivered from an AC power source to an electrical load located in a space of a building, the load control system comprising:

a sensor mounted to detect an occupancy condition or a vacancy condition in the space; and

a load control device adapted to be coupled in series between the source and the load for controlling the amount of power delivered to the lighting load, the load control device responsive to the sensor to control the intensity of the lighting load;

wherein the load control system operates as though the sensor is an occupancy sensor when the load control system is operating in a first mode of operation, defined for a first predetermined period of time, and as though the sensor is a vacancy sensor when the load control system is operating in a second mode of operation, defined for a second predetermined period of time, the load control system operable to automatically change between the first and second modes of operation in response to the present time of day.

2. The load control system of claim 1, wherein the sensor is operable to transmit digital messages to the load control device in response to detecting an occupancy condition or a vacancy condition in the space.

3. The load control system of claim 2, wherein the sensor transmits digital messages including either occupancy commands or vacancy commands to the load control device, the load control device responding to both digital messages including occupancy commands and digital messages including vacancy commands in the first mode of operation, the load control device responding to only digital messages including vacancy commands in the second mode of operation.

4. The load control system of claim 3, wherein the load control device comprises an astronomical timeclock for determining a present time of the day, such that the load control device is operable to automatically change between the first and second modes of operation in response to the present time of the day.

5. The load control system of claim 2, wherein the sensor operates in the first mode of operation to transmit digital messages including occupancy and vacancy commands to the load control device in the first mode of operation, and transmits only digital messages including vacant commands to the load control device in the second mode of operation, such that the load control device does not turn the load on when the sensor detects the occupancy condition in the second mode of operation.

6. The load control system of claim 5, wherein the load control device comprises an astronomical timeclock for determining a present time of the day, such that the load control device is operable to automatically change between the first and second modes of operation in response to the present time of the day.

7. The load control system of claim 2, wherein the electrical load comprises a lighting load, and the load control device comprises a dimmer switch for adjusting the amount of power delivered to the lighting load.

8. The load control system of claim 2, wherein the electrical load comprises a lighting load, and the load control device comprises an electronic switch for toggling the lighting load on and off.

9. The load control system of claim 1, further comprising:

a central controller operable to transmit digital messages to the load control device in response to the sensor detecting the occupancy condition or the vacancy condition in the space, the central controller operating in the first mode of operation to turn the load on when the sensor detects the occupancy condition and to turn the load off when the sensor detects the vacancy condition, and operating in the second mode of operation to turn the load off when the sensor detects the vacancy condition, the central controller not turning the load on when the sensor detects the occupancy condition in the second mode of operation.

10. The load control system of claim 9, wherein the central controller comprises an astronomical timeclock for determining a present time of the day, such that the central controller is operable to automatically change between the first and second modes of operation in response to the present time of the day.

11. The load control system of claim 9, wherein the load control device comprises a ballast for controlling the intensity of a fluorescent lamp, the ballast coupled to the central controller via a communication link for receiving the digital message from the central controller.

12. The load control system of claim 9, further comprising:

a keypad device having a button for receiving a user input, and coupled to the central controller via a communication link, the keypad device operable to transmit the digital message to the central controller in response to an actuation of the button;

wherein the central controller is operable to change between the first and second modes of operation in response to an actuation of the button of the keypad.

13. The load control system of claim 9, further comprising:

a contact-closure input device for receiving a contact-closure input from a contact-closure output device, the contact-closure input device coupled to the central controller via a communication link, the contact-closure input device operable to transmit the digital message to the central controller in response to receiving the contact-closure input;

wherein the central controller is operable to change between the first and second modes of operation in response to the contact-closure input device receiving the contact-closure input.

14. The load control system of claim 9, further comprising:

a contact-closure input device coupled to the sensor for receiving a contact-closure input from the sensor, the contact-closure input device coupled to the central controller via a communication link, the contact-closure input device operable to transmit a digital message to the central controller in response to the sensor detecting the presence or absence of the occupant in the space.

15. The load control system of claim 9, wherein the load control device comprises a ballast for controlling the intensity of a fluorescent lamp, the ballast coupled to a communication link for receiving the digital messages from the central controller, the ballast further coupled to the sensor, such that the ballast is operable to transmit digital message to the central controller in response to the sensor detecting the presence or absence of the occupant in the space.

16. The load control system of claim 9, wherein the central controller comprises an astronomical timeclock for determining a present time of the day, the central controller operable to change between the first and second modes of operation in response to the present time of the day.

17. A load control device for controlling the amount of power delivered from an AC power source to a lighting load located in a space of a building, the load control device comprising:

a load control circuit adapted to be coupled in series between the source and the load for controlling the amount of power delivered to the load;

a sensor for detecting the presence and absence of an occupant in the space; and

an internal controller operatively coupled to the load control circuit and the sensor for controlling the intensity of the load in response to the sensor, the internal controller operable to operate in first and second modes of operation, the first mode of operation being defined for a first predetermined period of time and the second mode of operation being defined for a second predetermined period of time, the internal controller operable to automatically change between the first and second modes of operation in response to the present time of day;

wherein the load control device operates as an occupancy sensor when the internal controller is operating in a first mode of operation, and as a vacancy sensor when the internal controller is operating in a second mode of operation.

18. The load control device of claim 17, wherein while the internal controller is operating in the first mode of operation, the internal controller turns the lighting load on when the sensor detects the presence of the occupant and turns the lighting load off when the sensor detects the absence of the occupant;

and

wherein while the internal controller is operating in the second mode of operation, the internal controller turns the lighting load off when the sensor detects the absence of the occupant and does not turn the lighting load on when the sensor detects the presence of the occupant.

19. The load control device of claim 18, wherein the sensor comprises a passive infrared detector, the load control device further comprising a toggle actuator operatively coupled to the internal controller and a lens positioned adjacent the toggle actuator, the internal controller operable to toggle the load on and off in response to actuations of the toggle actuator, the lens operable to direct infrared energy from the occupant towards the passive infrared detector.

20. The load control device of claim 18, wherein the internal controller comprises an astronomical timeclock for determining a present time of the day, such that the internal controller is operable to automatically change between the first and second modes of operation in response to the present time of the day.