Digital Lighting Control Method and System

Abstract

A system for controlling LED light fixtures such that in the event of a loss of the lighting control signal the LED light fixtures may be controlled in a proper and predictable manner. The system includes a Digital Power Module (DPM) that receives the lighting control signal and transmits a control signal to a Fixture Control Module (FCM) connected to the LED lights. In the event the lighting control signal is not received by the DPM, it is adapted to send a backup control signal to the FCM to control the LEDs. Additionally, in the event the DPM fails to send a control signal to the FCM, the FCM is adapted to control the LEDs is a predefined manner such that the LEDs are always functional even with a loss of the input control signal.

Claims

1. A lighting control system for use in controlling LED light fixtures comprising: a Digital Power Module (DPM) having: a power input adapted to be connected to a source of electrical power; a control input adapted to receive a lighting control signal from a control input device; a controller; a storage coupled to said controller; an output; a Fixture Control Module (FCM) having: an input adapted to be connected to the output of the DPM; and an LED light fixture connected thereto; in the presence of the lighting control signal, said DPM being operable to transmit a control output signal on said output, based on the lighting control signal, such that the LED light fixture is controlled according to the lighting control signal; and in the event of a loss of the lighting control signal, said DPM being operable to transmit a backup control signal on said output such that said LED light fixture is controlled according to said backup control signal.

2. The lighting control system according to claim 1 wherein said lighting control signal is selected from the group consisting of: Digital Muliplex (DMX), Digital Addressable Lighting Interface (DALI), a 0-10V input and combinations thereof.

3. The lighting control system according to claim 1 wherein said controller is selected from the group consisting of: a computer, a digital signal processor, a field-programmable gate array, an application-specific integrated circuit, a micro-processor, a micro-controller, or combinations thereof.

4. The lighting control system according to claim 1 wherein said DPM has a plurality of outputs, further comprising a plurality of FCMs connected to said plurality of outputs, and said backup control signal comprises a plurality of backup control signals sent on said plurality of outputs respectively.

5. The lighting control system according to claim 1 wherein said storage has a program saved thereon and said program is adapted to control said LED light fixture to a specified light level or a specified color temperature.

6. The lighting control system according to claim 5 wherein said program generates said plurality of backup control signals such that each of said plurality of outputs is controlled independently from each other.

7. The lighting control system according to claim 6 wherein each of said plurality of outputs is controlled such that the respective LED light fixture connected thereto is controlled differently from the LED light fixtures connected to the other outputs.

8. The lighting control system according to claim 5 wherein said program uses a last received lighting control signal when generating said backup control signal.

9. The lighting control system according to claim 5 wherein the backup signal corresponds to a 0-10V dimmer signal.

10. The lighting control system according to claim 1 wherein a determination of the loss of the lighting control signal is based on an elapse of a time period or a lack of receipt of data packets.

11. The lighting control system according to claim 10 wherein said time period is programmable.

12. The lighting control system according to claim 1 wherein said backup control signal is adapted to operate the LED light fixture in a manner providing a visual indication of the loss of the lighting control signal.

13. The lighting control system according to claim 12 wherein said backup control signal causes the LED light fixtures to pulse or flash.

14. The lighting control system according to claim 1 wherein said FCM comprises a processor and a storage.

15. The lighting control system according to claim 13 wherein said storage comprises an address or a program.

16. The lighting control system according to claim 15 wherein said FCM further comprises a processor and a FCM storage, and in the event said DPM fails to transmit the control output signal to the FCM, said FCM is adapted to operate said LED light fixture in a default mode.

17. The lighting control system according to claim 16 wherein said default mode is based on a last received lighting control signal or on based on data saved on said FCM storage.

18. A method for controlling LED light fixtures comprising the steps of: transmitting electrical power to a Digital Power Module (DPM); transmitting a lighting control signal to an input of the DPM; transmitting an output signal on an output, where said output is connected to a Fixture Control Module (FCM) that is connected to an LED light fixture; controlling LED light fixture based on the lighting control signal; wherein in the event of a loss of the lighting control signal, the DPM transmits a backup control signal on the output such that the LED light fixture is controlled according to the backup control signal.

19. The method according to claim 18 wherein the DPM includes a controller and a storage, the method further comprising the step of: controlling the LED light fixtures to a specified light level or a specified color temperature with the backup control signal.

20. The method according to claim 18 wherein a determination of the loss of the lighting control signal is based the elapse of a time period or a lack of receipt of data packets.

21. The method according to claim 18 further comprising the step of: transmitting a signal to a computer via a network related to a measured temperature.

22. The method according to claim 18 further comprising the step of: operating said LED light fixtures in a predetermined mode in the event of an overtemperature condition.

23. A lighting control system for use in controlling LED light fixtures comprising: a Digital Power Module (DPM) having: a power input adapted to be connected to a source of electrical power; a control input adapted to receive a lighting control signal from a control input device; a controller; an output adapted to transmit a control signal; a Fixture Control Module (FCM) having: an input adapted to be connected to said output and receive the control signal; a processor; a storage coupled to said processor; and an LED light fixture connected thereto; in the presence of the lighting control signal, said DPM being operable to transmit a control output signal on said output, based on the lighting control signal, such that the LED light fixture is controlled according to the lighting control signal; and in the event said DPM fails to transmit the control output signal to the FCM, said FCM is adapted to operate said LED light fixture in a default mode.

24. The lighting control system according to claim 23 wherein said lighting control signal is selected from the group consisting of: Digital Muliplex (DMX), Digital Addressable Lighting Interface (DALI), a 0-10V input and combinations thereof.

25. The lighting control system according to claim 23 wherein said storage has a program saved thereon and said program is adapted to control said LED light fixtures to a specified light level or a specified color temperature.

26. The lighting control system according to claim 25 wherein said program uses a last received control signal when operating said LED light fixtures in said default mode.

27. The lighting control system according to claim 23 wherein in said default mode said FCM is adapted to operate the LED light fixture in a manner providing a visual indication of the loss of the lighting control signal.

28. The lighting control system according to claim 23 further comprising a thermistor located in said FCM and adapted to measure a temperature near said LED light fixture.

29. The lighting control system according to claim 28 wherein said LED light fixture is operated in a predetermined mode in the event of an over-temperature condition.

30. The lighting control system according to claim 23 wherein said storage comprises an address.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG. 1 is a block diagram of one configuration of the lighting control system illustrating a DPM connected to a plurality of LED light fixtures.

[0030] FIG. 2 is a block diagram according to FIG. 1 illustrating the FCM in greater detail.

[0031] FIG. 3 is a block diagram according to FIG. 1 illustrating the LED light fixture in greater detail.

[0032] FIG. 4 is a block diagram according to FIG. 1 illustrating a plurality of DPMs connected to a computer via a network connection.

[0033] FIG. 5 is a block diagram according to FIG. 1 illustrating control inputs in greater detail to the DPM.

DETAILED DESCRIPTION OF THE INVENTION

[0034] Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views.

[0035] With reference to FIG. 1, a lighting control system 100 for use with LEDs light fixtures 202, 202, 202 are provided for use in various lighting environments. The system generally includes, a Digital Power Module (DPM) 102 that has a Power input 110 (e.g., an A/C or D/C power connection), a lighting control input 112 that may be wired or wireless, and a program input 114. The DPM 102 may further comprise a plurality of channels 108, 108, 108, which are adapted to be coupled to LED light fixtures 202, 202, 202. The DPM 102 is illustrated comprising a controller 104 including a storage 106. The controller 104 may comprise, for example, a computer, a digital signal processor, a field-programmable gate array, an application-specific integrated circuit, a micro-processor, a micro-controller, or any other form of programmable hardware.

[0036] The LED light fixtures 202, 202, 202 are illustrated being remotely located from and connected to the DPM 102 via channel 108, 108, 108 by wiring 116, 116, 116 respectively. Each LED light fixture 202, 202, 202 includes a Fixture Control Module (FCM) 204, 204, 204. Wiring 116, 116, 116 may comprise low-voltage wiring, through which power and (optionally) control signals are separately transmitted between DPM 102 and FCM 204, 204, 204. Additional LED lighting fixtures (not shown) may be connected to each channel, such as in a daisy-chain configuration. For this purpose, the FCM can include a DC power output and a control signal output (not shown) to relay power and control signals to the additional fixtures.

[0037] Turning now to FIG. 2 the FCM 204 is illustrated in greater detail. Additionally, an expanded view of the various signals being transmitted via wiring 116 is illustrated. Channel 120 of DPM 102 is used to output DC power 120 (48V) from DPM 102 to FCM 204 and is received by DC input power connection 210. Digital control inputs 122 are also transmitted from DPM 102 to FCM 204 and is received by control signal input connection 212. Additionally, a program input 124 is transmitted from DPM 102 to FCM 204.

[0038] FCM 204 is provided with a processor 206 that may include a storage 208, which may or may comprise firmware including an address. A storage 214 is also illustrated for storing a program and data thereon. Additionally, or alternatively, a manual switch 216 is illustrated on FCM 204. It is contemplated that any or all of these various components may be used or omitted in the FCM 204. In one configuration, the processor 206 includes firmware that has an address located thereon such that the FCM 204 may be located via a network connection for transmission of data to control the FCM and associated LEDs. In another configuration, the storage 214 includes a program such that the associated LEDs could be controlled based upon instructions received by the FCM 204 and by the program saved on the storage 214. In still another configuration, the FCM 204 could have an address set by configuring the manual switch 216, which could comprise a DIP switch including a plurality of switch positions.

[0039] Also shown in FIG. 2 is temperature sensor 218, which may comprise, for example, a thermistor. A thermistor is a device that will change resistance based on the surrounding ambient temperature thereby allowing the FCM 204 to measure the temperature in the vicinity of the FCM 204. The temperature signal that is generated by the temperature sensor 218 may be received by the processor 206 and processed, and optionally such that it may be transmitted via data output 126 to DPM 102. The temperature sensor 218 is illustrated as external to processor 206, however, it is contemplated that temperature sensor 218 may be provided integral with processor 206 (this alternative configuration is illustrated with the T.S. in dashed line inside processor 206).

[0040] FCM 204 is provided with a DC power output 220 and a control output 222, which are adapted to be coupled to LED lights positioned within the LED light fixture 202. Optionally, the FCM can drive the LED lights with the DC power output 220, such as by analog modulation or a pulse-width modulation (PWM) technique.

[0041] FIG. 3 illustrates the LED lights 230, 230, 230, 230.sup.n within LED light fixture 202. LED lights 230, 230, 230, 230.sup.n may include, for example, from between one to twelve LEDs and comprise RGBW allowing for virtually any color to be generated. The FCM is operable to drive the LEDs to produce a plurality of light colors and/or to dim the LED lights 230, 230, 230, 230.sup.n to produce a plurality of light intensities, in response to the control signal received from the DPM. The FCM can include a separate power output and/or control signal for each LED light.

[0042] In one configuration, data received by FCM 204 may be in the form of an RS-485 data stream that when decoded, provide brightness level data in an 8-bit format. One to four bytes of data (one per color) could be outputted from the controller port as Pulse Width Modulated (PWM) signals with the pulse width proportional to the brightness level of the received data. Analog modulation of the LED's may also be used with the FCM 204.

[0043] In one example, during operation one to four voltage-to-constant current buck-down converters or analog FETs with D/A conversion will drive the one through four strings of LED's each comprising 1-12 LED(s) with the dimming function allowing for ON and OFF control via the PWM signal or analog controlling current through the LED rows to dim the LED rows internal to the fixture. The FCM PCB may have one or two RJ type Cat-5 compatible (or other suitable) connectors for connection to the DPM and additional FCMs/LED light fixtures. The 48 VDC used to power the controller and the LED(s) can also be supplied over the low voltage cable.

[0044] FIG. 4 illustrates the DPM 102 having a variety of lighting control inputs 112 (interfaces). For example, lighting control input 112 could comprise a DMX input 140, a DALI input 142 or a 0-10V input 144. These lighting control inputs 112 are separate and apart from program input 114.

[0045] 0-10V input 144 may comprise an analog 0-10V dimmer type of control, which in one configuration could comprise two dimmers (e.g., one for color and one for brightness). In addition to these controls, the system could use a DMX digital control interface. When some or all of these controls are provided, the DPM allows for some new and unique ways to address interface failures and still allow some user control to the LED light fixtures. For example, assuming RGBW LED light fixtures are connected to the DPM and the DPM is set to DMX interface; if the DMX controller connected to the DPM fails, firmware (or software) in the DPM could be programmed to also be looking at the 0-10V dimmer control so as to allow a user to turn on and off and dim a white light (or pre-programmed color) when the DMX control interface is not functioning properly (e.g., the backup control signal corresponds to the dimmer control). While lighting control input 112 is illustrated as a wired connection, it is contemplated that either a wired or wireless connection to DPM 102 may effectively be utilized. Likewise, it is contemplated that program input 114 may comprise either a wired or wireless connection. In both cases, a Blue Tooth connection could be used to send signals to the DPM. It could be convenient to wirelessly connect to the DPM via program input 114 via a handheld tablet device for programming the system. Alternatively, a tablet could be located in room (conference room) and could be used to control the lighting including the setting of various scenes having preselected color and brightness levels.

[0046] Alternatively, if a 0-10V dimmer is not connected to the system, then the system could interpret the 0-10V control input as a 0-10V dimmer set to full (100%) brightness, which in turn would cause the DPM to set the light fixture to fully ON. Alternatively, the DPM could be pre-programmed to drive the LED light fixture at a different brightness level (e.g., 80% or 60%, etc.). This assures that the system 100 will continue to provide illuminating light even if the DMX wireless control interface fails to function properly by means of a backup control signal. It is contemplated that the program input 114 could be used to program controller 104 for default settings in the event of a loss of the lighting control signal. Additionally, it is contemplated that program input could be used to program the FCM 204 (e.g., firmware on processor 206 or saving of a program on storage 214, etc.).

[0047] FIG. 5 illustrates a number of different DPMs 102, each with their respective LED light fixtures 202 and FCMs 204 in accordance with FIGS. 1-4. However, also depicted in FIG. 5 is computer 302, which is variously connected to the DPMs 102 via network connection 304. The network connection may comprise for example, the Internet. Computer 302 may be used to remotely monitor the status and control of the various DPMs 102 and LED light fixtures 202 connected thereto. It is contemplated that in one configuration, two way communication can be provided between computer 302 and LED light fixtures 202.

[0048] The system 100 can be adjusted to monitor for a loss of the lighting control signal to the DPM 102. In this regard, the following process may be implemented: 1. Set light color to predetermined color (e.g., white or other color); and 2) Set the light intensity based on a 0-10V control signal level, if present, or if not, to a predetermined level (e.g., 100%, 80%, 45% and so on).

[0049] In the event of a return of the lighting control signal to the DPM 102 after a determination of a loss of the lighting control signal, the system may resume normal operation and allows for the resumption of the remote digital control setting.

[0050] As was previously stated, when discussing what is a loss of control (e.g., a digital control signal), this refers to a state in which no valid signal is received by the receiving device, which in this case, would be DPM 102 monitoring for a lighting control signal. The loss of the lighting control signal could be determined over a predetermined period of time and/or a predetermined number of data packets. The time between when the last valid (understandable) signal was received and a determination of loss of the lighting control signal could can be programmable and set in controller 104 via program input 114. In one example, an instantaneous loss of a valid signal (e.g., a loss of one second or less) could be interpreted as a loss of a lighting control signal, or not receiving a valid signal for a time exceeding one minute (or any other time frame) could be interpreted as a loss of a lighting control signal. Lack of a valid signal for less than the predetermined time and/or predetermined number of packets could simply be ignored by system 100.

[0051] A determination of a return of the lighting control signal could occur immediately upon resumption of a valid lighting control signal (e.g., within one second or less), or could occur after a predetermined delay (e.g., after 15 seconds or some other time frame), or even after receipt of a number of valid data packets. A resumption of a valid signal for less than the predetermined time could be ignored by system 100. Likewise, a re-occurrence of a loss of the lighting control signal during the predetermined time could cause the delay period to re-initiate.

[0052] Another possible failure point is the DPM 102. It is understood that the DPM could receive a valid lighting control signal, but still fail to send or relay a valid control signal(s) to the connected LED light fixtures 202, 202, 202. If the connected LED light fixtures are still being supplied with DC power, the LEDs could be set to a desired state as a preprogrammed setting.

[0053] In one example, the FCM 204 monitors for a lighting control signal transmitted through channel 108 along wiring 116. When a loss of a lighting control signal to the FCM 204 occurs, the FCM 204 could operate to set the LEDs with a default mode to the last valid state corresponding to the last valid lighting control signal received from DPM 102. Alternatively, the default mode from the FCM 204 could set the LEDs to a predetermined color and/or brightness according to a program or data saved in storage 208, 214. Alternatively or additionally, the FCM could operate the LED lights in a manner to provide a visual indication to those in the area, of the loss of the lighting control signal. This could be accomplished, for example, by pulsing or flashing the LEDs at regular or irregular intervals. On a return of a valid lighting control signal to the DPM 102, the system 100 will cease using the default mode and resume control based on the lighting control signal received. The determinations of loss of the lighting control signal to the FCM 204 and resumption of the lighting control signal to the FCM 204 could be made in similar manners as described above with respect to the DPM 102.

[0054] Still another potential mode of failure of the LED light fixtures 202, 202, 202, is light fixture over temperature. In one configuration, the temperature sensor 218 generates a temperature signal indicative of a temperature in the area of the sensor 218. Likewise, the temperature sensor 218 could comprise a plurality of temperature sensors (e.g., illustrated in FIG. 3 with dashed line) adapted to monitor various independent components of the LED light fixture 202. In the event of an over temperature (temperature reaching or exceeding a predetermined maximum temperature threshold for longer than a predetermined period of time), the processor 206 may then set the LED light fixture 202 to a predetermined mode or setting. This predetermined mode or setting could be: to dim the LEDs to a predetermined level, or turn off, or pulse/blink at an interval.

[0055] When the temperature returns to normal, the system 100 could then resume normal operation. For example, a return to normal temperature can be when the temperature falls to or below a resumption temperature threshold (saved in storage 208, 214) for a predetermined amount of time, where the resumption temperature threshold may be the same as or lower than the maximum temperature threshold. Likewise, the predetermined amount of time may be instantaneous or some other setting.

[0056] It will be understood by those of skill in the art that this function can be programmable where the maximum and resumption temperature thresholds, and the predetermined periods of time may be selectable.

[0057] Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art.