Intelligent light retrofit

1. A method of retrofitting a light fixture, comprising:

interfacing a retrofit controller with a dimming ballast of the light fixture;

connecting the retrofit controller to at least one sensor; and

connecting the retrofit controller to a power supply and a network; wherein the retrofit controller provides low-power to the at least one sensor, allowing the at least one sensor to be electrically connected, removed and replaced without an electrician.

2. The method of claim 1 , wherein the retrofit controller is connected to the network through the at least one sensor.

3. The method of claim 1 , wherein the retrofit controller is connected to the network through a power line.

4. The method of claim 1 , wherein interfacing the retrofit controller with the dimming ballast comprises breaking existing power supply and dimming control connections of the dimming ballast, inserting the retrofit controller, and connecting the power supply and dimming connections of the dimming ballast to the retrofit controller, while maintaining existing electrical switch and wiring connections.

5. The method of claim 1 , further comprising the retrofit controller receiving sensed information from the at least one sensor, and adaptively controlling the dimming ballast based on the sensed information.

6. The method of claim 5 , wherein the sensed information comprises a combination of sensed light, sensed motion, and sensed temperature.

7. The method of claim 1 , further comprising the retrofit controller receiving control information from other retrofit controllers over the network.

8. The method of claim 1 , further comprising providing a manual over-ride, allowing manual input control of dimming control of the dimming ballast utilizing an existing dimming control mechanism.

9. A method of retrofitting a light fixture, comprising:

interfacing a retrofit controller with a dimming ballast of the light fixture;

connecting the retrofit controller to at least one sensor; and

connecting the retrofit controller to a power supply and a network;

wherein connecting the retrofit controller to at least one sensor comprises attaching an external electrically conductive line between at least one external sensor and the retrofit controller; and

wherein the external electrically conductive line provides power to the at least one external sensor from the retrofit controller.

10. The method of claim 9 , further comprising affixing the at least one external sensor proximate to the light fixture.

11. The method of claim 9 , wherein the external electrically conductive line provides at least one of sensor and control information from the at least one external sensor to the retrofit controller.

12. The method of claim 11 , further comprising the at least one external sensor comprising a controller, and the at least one external sensor being wirelessly connected to a network.

13. The method of claim 12 , further comprising the at least one external sensor providing dimming control information to the retrofit controller based on at least one of sensed information and control information received from the network.

14. A light fixture retrofit kit comprising:

a sensor unit and a dimming controller; wherein

the sensor unit comprises;

a sensor, the sensor operative to generate a sensed signal based on at least one of sensed motion or light;

wireless communication circuitry, the wireless communication circuitry operative to maintain a wireless link with a network;

a controller, the controller operative to manage communication with the network, and to generate dimming control based on at least one of the sensed signal and communication from the network; and

wherein

the dimming controller comprises;

means for receiving the dimming control and operative to adjust a dimming control line to a light ballast.

15. The retrofit kit of claim 14 , further comprising a flat electrical cable for providing electrical power from the dimming controller to the sensor unit, and providing control lines from the sensor unit to the dimming controller.

16. The retrofit kit of claim 14 , further comprising the dimming controller operative to identify a sequence of power cycling, and transferring dimming control to a manual switch when a predetermined sequence of power cycling is received.