Patent Publication Number: US-8525420-B2

Title: Luminaire having a HID light source and a LED light source

Description:
CROSS-REFERENCE TO RELATED DOCUMENTS 
     Not Applicable. 
     TECHNICAL FIELD 
     This invention pertains to a luminaire having a HID light source and a LED light source. 
     BACKGROUND 
     Luminaires used for area or outdoor lighting may include a housing that surrounds one or more high intensity discharge (HID) lamps such as, for example, Metal Halide (MH), Pulse Start Metal Halide (PSMH), or High Pressure Sodium (HPS) HID lamp(s). The one or more HID lamps are the sole light source in such luminaires and are typically activated when artificial lighting is needed. The housing may be coupled to a support surface such as, for example, a support pole or a wall of a building. 
     Other luminaires used for area or outdoor lighting may include a housing that surrounds an LED light source having one or more solid state light emitting diodes (LEDs) producing a lumen output similar to that of one or more HID lamps. The one or more LEDs are the sole light source in such luminaires and are typically activated when artificial lighting is needed. The housing may be coupled to a support surface such as, for example, a support pole or a wall of a building. 
     SUMMARY 
     Generally, in one aspect a luminaire includes a LED arm assembly and a primary HID light source housing coupled to the LED arm assembly. The primary light source housing has a light exit aperture. At least one selectively powerable HID lamp is enclosed in the primary HID light source housing. A selectively powerable secondary LED light source is coupled to the LED arm assembly between the pole and the primary light source housing and the secondary LED light source has a plurality of LEDs selectively producing a downwardly directed light output. The HID ballast powers the HID lamp during user selected peak hours and does not power the HID lamp during user selected non-peak hours. The at least one driver powers the secondary LED light source during the non-peak hours and does not power the secondary LED light source during the peak hours. The luminaire also includes a first and a second mutually independent power supply. The first power supply is in electrical connection with the HID lamp and the second power supply is in electrical connection with the secondary LED light source. 
     In some embodiments the LED arm assembly may have a downwardly facing bottom surface supporting the plurality of LEDs. The bottom surface may optionally be substantially planar and substantially perpendicular to the pole. In versions of these embodiments the plurality of LEDs may be mounted on a printed circuit board comprising at least a majority of the substantially planar bottom surface of the LED arm assembly and extending from adjacent the pole to adjacent the primary light source housing. 
     In some embodiments the LED arm assembly may enclose the second power supply. In versions of these embodiments the LED arm assembly may enclose the first power supply. In versions of these embodiments the LED arm assembly may enclose a signal receiving controller connected to the first power supply and the second power supply, the signal receiving controller selectively causing power to be routed to either the first power supply or the second power supply. 
     Generally, in another aspect, a luminaire includes a primary light source housing coupled to a support structure, the primary light source housing having a downwardly facing light exit aperture. At least one selectively powerable HID lamp is enclosed in the primary light source housing and electrically connected to an HID ballast. The HID lamp selectively produces a downwardly directed HID light output. A longitudinally extending LED arm assembly extends from the support structure, the LED arm assembly having a downwardly facing bottom surface. A selectively powerable secondary LED light source is coupled to the bottom surface of the LED arm assembly and has a plurality of LEDs electrically connected to at least one driver and selectively producing a downwardly directed LED light output. The luminosity of the HID light output is at least two times greater than the luminosity of the LED light output. The HID ballast powers the HID lamp during user selected peak hours. The at least one driver powers the secondary LED light source during user selected non-peak hours and mutually exclusive of the HID ballast powering the HID lamp. 
     In some embodiments the LED arm assembly may include a heatsink in thermal connectivity with the LED light source, the heatsink comprising a plurality of heat fins exposed to the external environment. In some versions of those embodiments the heat fins may be longitudinally extending and placed at an upwardly extending non-perpendicular and non-parallel angle with respect to the printed circuit board. In some versions of those embodiments the plurality of LEDs may be mounted on a printed circuit board coupled to the heatsink, the printed circuit board comprising at least a majority of the bottom surface of the primary light source LED arm assembly and extending from adjacent the support structure to adjacent the primary light source housing. In some versions of those embodiments the LED arm assembly may extend between the support structure and the primary light source housing and support the primary light source housing. The LED arm assembly may enclose the HID ballast and at least one driver electrically connected to the secondary LED light source. The heatsink may optionally contact the at least one driver. 
     Generally, in another aspect a luminaire includes a LED arm assembly extending from a pole; a primary light source housing coupled to the support arm, the primary light source housing having a light exit aperture; at least one selectively powerable HID lamp enclosed in the primary light source housing and electrically connected to an HID ballast, the HID lamp selectively producing a directed HID light output; a longitudinally extending stand alone arm LED assembly extending from the support surface, the LED arm assembly having a longitudinally extending heatsink with a downwardly facing contact surface; a selectively powerable secondary LED light source coupled to the contact surface of the heatsink and having a plurality of LEDs electrically connected to at least one driver enclosed in the LED arm assembly, the LED light source selectively producing a downwardly directed LED light output; wherein the luminosity of the HID light output is at least three times greater than the luminosity of the LED light output; wherein the HID light source consumes at least two times as much power as the LED light source; and wherein the HID ballast powers the HID lamp during user selected peak hours and does not power the HID lamp during user selected non-peak hours, and wherein the at least one driver powers the secondary LED light source during the non-peak hours and does not power the secondary LED light source during the peak hours. 
     In some embodiments the heatsink may have a plurality of heat fins exposed to the external environment. In some versions of those embodiments the plurality of LEDs may be mounted on a printed circuit board coupled to the heatsink, the printed circuit board comprising at least a majority of the bottom surface of the primary light source LED arm assembly. In some versions of those embodiments the heat fins may be longitudinally extending and placed at an upward non-perpendicular and non-parallel angle with respect to the printed circuit board. In some versions of those embodiments the stand alone arm assembly may enclose the at least one ballast electrically connected to the HID lamp. The heatsink may form sidewalls of the LED arm assembly, the sidewalls extending between a front endcap and a rear endcap of the LED arm assembly. 
     The term “controller” is used herein generally to describe various apparatus relating to the operation of one or more light sources. A controller can be implemented in numerous ways (e.g., such as with dedicated hardware) to perform various functions discussed herein. A “processor” is one example of a controller which employs one or more microprocessors that may be programmed using software (e.g., microcode) to perform various functions discussed herein. A controller may be implemented with or without employing a processor, and also may be implemented as a combination of dedicated hardware to perform some functions and a processor (e.g., one or more programmed microprocessors and associated circuitry) to perform other functions. Examples of controller components that may be employed in various embodiments of the present disclosure include, but are not limited to, conventional microprocessors, application specific integrated circuits (ASICs), and field-programmable gate arrays (FPGAs). 
     In various implementations, a processor or controller may be associated with one or more storage media (generically referred to herein as “memory,” e.g., volatile and non-volatile computer memory such as RAM, PROM, EPROM, and EEPROM, floppy disks, compact disks, optical disks, magnetic tape, etc.). In some implementations, the storage media may be encoded with one or more programs that, when executed on one or more processors and/or controllers, perform at least some of the functions discussed herein. Various storage media may be fixed within a processor or controller or may be transportable, such that the one or more programs stored thereon can be loaded into a processor or controller so as to implement various aspects of the present invention discussed herein. The terms “program” or “computer program” are used herein in a generic sense to refer to any type of computer code (e.g., software or microcode) that can be employed to program one or more processors or controllers. 
     As used herein for purposes of the present disclosure, the term “LED” should be understood to include any electroluminescent diode or other type of carrier injection/junction-based system that is capable of generating radiation in response to an electric signal. Thus, the term LED includes, but is not limited to, various semiconductor-based structures that emit light in response to current, light emitting polymers, organic light emitting diodes (OLEDs), electroluminescent strips, and the like. In particular, the term LED refers to light emitting diodes of all types (including semi-conductor and organic light emitting diodes) that may be configured to generate radiation in one or more of the infrared spectrum, ultraviolet spectrum, and various portions of the visible spectrum (generally including radiation wavelengths from approximately 400 nanometers to approximately 700 nanometers). Some examples of LEDs include, but are not limited to, various types of infrared LEDs, ultraviolet LEDs, red LEDs, blue LEDs, green LEDs, yellow LEDs, amber LEDs, orange LEDs, and white LEDs (discussed further below). It also should be appreciated that LEDs may be configured and/or controlled to generate radiation having various bandwidths (e.g., full widths at half maximum, or FWHM) for a given spectrum (e.g., narrow bandwidth, broad bandwidth), and a variety of dominant wavelengths within a given general color categorization. 
     As used herein for purposes of the present disclosure, the term “HID lamp” should be understood to include, but not be limited to, any non-LED based lamp that has performance characteristics similar to the group of lamps known as mercury, metal halide, and high pressure sodium. The term HID lamp specifically includes, but is not limited to, inductive discharge lamps that operate using the principal of induction. 
    
    
     
       BRIEF DESCRIPTION OF THE ILLUSTRATIONS 
       In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. 
         FIG. 1  illustrates a bottom perspective view of a first embodiment of a luminaire having a HID light source and an LED light source. 
         FIG. 2  illustrates a close up bottom perspective view of a LED arm assembly of the first embodiment with a printed circuit board exploded away and a single LED lens exploded away. 
         FIG. 3  illustrates an exploded top perspective view of the first embodiment of the luminaire. 
         FIG. 4  illustrates a close up view of an LED arm assembly of a second embodiment of a luminaire having a HID light source and an LED light source 
         FIG. 5  illustrates a bottom perspective view of a single LED lens of the first embodiment of the luminaire. 
         FIG. 6  illustrates an embodiment of a lighting network. 
         FIG. 7  illustrates a schematic diagram of an embodiment of a method of monitoring for a control signal and alternating between a first light source and a second light source. 
         FIG. 8  illustrates an embodiment of a control signal 
         FIG. 9  illustrates schematic diagram of an embodiment of a lighting controller of the lighting network of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION 
     It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” “in communication with” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms “connected” and “coupled” and variations thereof are not restricted to physical or mechanical connections or couplings. 
     Furthermore, and as described in subsequent paragraphs, the specific mechanical configurations illustrated in the drawings are intended to exemplify embodiments of the invention and that other alternative mechanical configurations are possible. 
     Referring to  FIGS. 1 through 5 , wherein like numerals refer to like parts, two embodiments of a luminaire having a HID light source and a LED light source are depicted. Referring initially to  FIG. 1  through  FIG. 3 , a first embodiment of a luminaire  10  having a HID light source and a LED light source is depicted. The luminaire  10  comprises a LED arm assembly  20  coupled to and extending from a support pole  5 . The LED arm assembly  20  has a secondary LED light source  40  thereon that selectively produces a secondary LED light output. A primary HID light source housing  50  is coupled to the LED arm assembly  20  and has an HID lamp  54  therein that selectively produces a primary HID light output. In alternative embodiments the LED arm assembly  20  and/or the LED light source  40  may be coupled to alternative support structures than support pole  5 . For example, in some embodiments the LED arm assembly  20  and/or the LED light source  40  may be coupled to a wall of a building or a support pole having a different configuration than support pole  5 . 
     The primary HID light source housing  50  has a lens  53  lying across an opening of the housing. The lens  53  has an opaque portion surrounding a transparent portion and defining a light exit opening  52 . In alternative configurations, alternative lens or lenses may be used, such as, for example, lens that are completely transparent, partially or completely diffuse, and/or non-planar. The HID lamp  54  is enclosed within the primary HID light source housing  50  and is surrounded by an HID reflector  55 . The light output from the HID lamp  54  is directed out light exit opening  52  downwardly toward a desired illumination area. In some embodiments the HID lamp  54  may be electrically connected to a HID ballast  89  ( FIG. 6 ) enclosed within the HID light source housing  50 . 
     In some embodiments the HID lamp  54  may be a 400 Watt PSMH lamp, consume approximately 462 watts of power, and provide approximately 20,000-30,000 mean lumens of light output. In other embodiments the HID lamp  54  may consume a different amount of Watts and/or output a different amount of Lumens. In alternative embodiments HID lamp  54  may be one or more MH or HPS lamps and may be of a different wattage such as, for example, 150, 320, and/or 350 Watts In some embodiments the HID ballast  89  may be a magnetic ballast configured to power a 400 Watt PSMH lamp. In some embodiments HID light source housing  50  and associated components may at least partially comprise a Philips AL3, AL3R, or EAL19 fixture. A front attachment piece  27  on LED arm assembly  20  attaches HID light source housing  50  to LED arm assembly  20 . As understood in the art, HID light source housing  50  may be configured to provide a desired photometric distribution such as, for example, an IES Type III or Type V distribution. 
     The LED arm assembly  20  has a rear attachment piece  24  that attaches to support pole  5 . The LED light source  30  of the LED arm assembly  20  has a printed circuit board  42  comprising a majority of the bottom surface of the LED arm assembly  20  and extending from adjacent the pole  5  to adjacent the primary light source housing  50 . In some embodiments the printed circuit board  42  may be an aluminum printed circuit board and in other embodiments the printed circuit board  42  may be an alternative printed circuit board such as, for example, a FR4 printed circuit board. The printed circuit board  42  supports LEDs  44 . In the depicted embodiment the LEDs  44  are twenty-one Lumiled Rebel LEDs. In alternative embodiments alternative LEDs  44  may be used. For example, one or more LEDs may be used that have alternative characteristics from the Lumiled Rebel LEDs depicted such as, for example, alternative lumen output, light distribution, color temperature and/or heat generating characteristics. An individual of a plurality of LED lenses  46  may be placed over each of the LEDs  44  and direct light output thereof. A single LED lens  46  is shown exploded away form the LED circuit board  142  in  FIG. 2  and a single LED lens  46  is shown in more detail in  FIG. 5 . Each depicted LED lens  46  is configured for the Lumiled Rebel LEDs to effectively disperse light emitted thereby to a predetermined desired photometric distribution. In other embodiments one or more LEDs may be provided without a lens and/or one or more LEDs may be provided with a lens having an alternative configuration. In some embodiments the LED light source  40  may consume approximately 20 to 35 Watts of power and may provide approximately 1500 to 3000 lumens of light output. In other embodiments the LED light source  40  may consume a different amount of Watts and/or output a different amount of Lumens. 
     The printed circuit board  42  is attached to and in thermal connectivity with a contact surface  32  of a longitudinally extending heatsink  30  of the LED arm assembly  20 . Thermal material may optionally be provided between the printed circuit board  42  and the contact surface  32 . In some embodiments the heatsink  30  may be an extruded aluminum heatsink  30 . The contact surface  32  is flanked by longitudinally extending lips  33  that also flank the printed circuit board  42 . The heatsink  30  has a plurality of longitudinally extending heat fins  32  on each longitudinal side thereof that are oriented at a non-perpendicular and non-parallel angle with respect to the printed circuit board  42 . In the depicted embodiment the heat fins  32  are at approximately a forty-five degree upward angle with respect to the printed circuit board  42 . The heatsink  30  has longitudinally extending sidewalls  36  disposed vertically above the heat fins  34 . The heatsink  30  extends from the rear attachment piece  24  of the LED arm assembly  20  to proximal the front attachment piece  27 . A pair of support rods  26  extends from the rear attachment piece  24  to the front attachment piece  27  and may be slidably received in corresponding pathways  39  of the heatsink  30  to support the heatsink  30 . 
     A top cover  22  may be placed atop the heatsink  30 . The top cover  22 , the heatsink  30 , the rear attachment piece  24 , and the front attachment piece  27  surround and enclose a transformer  82 , a signal receiver controller  84 , a normally closed relay switch  86 A, a normally open relay switch  86 B, and an LED driver  88 . The transformer  82  steps down the voltage of the external power supply and converts it to a DC voltage. For example, the transformer  82  may step down a 120V or 277V AC external power supply voltage and convert it to a 12V or 24V DC voltage. The DC voltage output of the transformer  82  is in electrical connectivity with the signal receiver controller  84 . Thus, signal receiving controller  84  is in indirect electrical connection with the external power supply. The signal receiver controller  84  has a control output that is in electrical connectivity with a control input of the normally closed relay switch  86 A and a control input of the normally open relay switch  86 B. The normally closed relay switch  86 A also has a relay power terminal in electrical connectivity with the external power supply and a normally closed control output in electrical connectivity with the HID ballast  89 . The normally open relay switch  86 B also has a relay power terminal in electrical connectivity with the external power supply and a normally open control output in electrical connectivity with the LED driver  88 . The LED driver  88  is in electrical connectivity with the printed circuit board  42  and the LEDs  44 . 
     The signal receiver controller  84  selectively provides a voltage over the control output to the control input of normally closed relay switch  86 A and the control input of normally open relay switch  86 B. When the voltage over the control output of the signal receiver controller  84  is above a threshold voltage, the normally closed relay switch  86 A is opened and the normally open relay switch  86 B is closed. Accordingly, when the voltage over the control output of the signal receiver controller  84  is above a threshold voltage the normally open relay switch  86 B routes the external power supply with the LED driver  88 , thereby causing the LED driver  88  (and the LEDs  44 ) to be powered. The normally closed relay switch  86 A is open and therefore does not route the external power supply to the HID ballast  89 . Conversely, when the voltage over the control output of the signal receiver controller  84  is below a threshold voltage (for example, when the voltage is zero), the normally closed relay switch  86 A is closed and the normally open relay switch  86 B is open. Accordingly, when the voltage over the control output of the signal receiver controller  84  is below a threshold voltage the normally closed relay switch  86 A routes the external power supply with the HID ballast  89 , thereby causing the HID ballast  89  (and the HID lamp  54 ) to be powered. The normally open relay switch  86 B is open and therefore does not route the external power supply to the LED driver  88 . 
     In some embodiments the signal receiver controller  84  may receive a control signal that determines whether the signal receiver controller  84  outputs a control output voltage that is above or below a threshold voltage and, as a result, determines whether the HID lamp  54  or the LEDs  44  are powered. In some embodiments the control signal may be received via the transformer  82 . For example, the control signal may be sent across an alternating current mains power line that is in electrical communication with the transformer  82 . In some embodiments the external power supply that feeds the transformer  82  may be in electrical communication with a lighting controller and/or a user actuable switch. For example, in some embodiments the external power supply that feeds the transformer  82  may be in electrical communication with a lighting controller that sends a control signal over the external power supply at desired times. In some embodiments the external power supply that feeds the transformer  82  may additionally or alternatively be in electrical communication with a user actuable switch that sends a control signal over the external power supply when it is actuated by a user. In some embodiments the lighting controller and/or the user actuable switch may be located remotely from luminaire  10  and may be in electrical communication with an external power supply that feeds multiple transformers  82  of multiple luminaires  10 . In some embodiments the LED driver  88  may be a Light Tech Inc. driver Model # LED-25-8V/12V/24V DCP. In some embodiments the transformer  82 , the relays  86 A and/or  86 B, and/or the LED drivers  88  may be in contact with and/or in thermal connectivity with one of the sidewalls  36  of heatsink  30 . 
     Although the transformer  82 , the signal receiver controller  84 , the relays  86 A and  86 B, the LED driver  88 , the HID ballast  89 , and the electrical connections therebetween are depicted and described in detail herein, other embodiments may implement other configurations. For example, in some embodiments multiple LED driver  88  may be provided. Also, for example, in some embodiments the transformer  82  may be integrated into the signal receiver controller  84 . Also, for example, in some embodiments the transformer  82  may be omitted and the signal receiver controller  84  may be configured to accept power directly from the external power supply. Also, for example, in some embodiments a transformer may be interposed between the HID ballast  89  and/or the LED driver  88  may be configured to receive DC voltage which may be provided via transformer  82  or a separate transformer. Also, for example, in some embodiments one, multiple, or all of the transformer  82 , the signal receiver controller  84 , and the LED driver  88  may be located external to the LED arm assembly  20 , such as, for example, in primary HID light source housing  50 , and/or in support pole  5 . Also, for example, in some embodiments the HID ballast  89  may be provided in the LED arm assembly  20 . Also, for example, in some embodiments the relays  86 A and  86 B may be combined into a single package. Also, for example, in some embodiments, multiple electrical connections between the signal receiver controller  84  and the relays  86 A and  86 B may be present. For example, in some embodiments each of the relays  86 A and  86 B may have an independent electrical coupling to the signal receiver controller  84 . In those embodiments and in other embodiments the relays  86 A and  86 B may optionally both be normally closed or normally opened relays. In some embodiments the relays  86 A and  86 B may be a Crydom D2425D Dual Solid State Relay. 
     In some embodiments only the HID lamp  54  may be activated during peak hours to provide an IES compliant level of illumination to an illumination area and only the LED light source  40  may be activated during off-peak hours to provide a level of illumination of a lower luminosity than that provided by the HID lamp  54 . In some embodiments peak hours may include a time period proximal to dusk until a predetermined time when pedestrian and/or vehicular traffic in an illumination area is anticipated to be minimal and a time period when pedestrian and/or vehicular traffic in an illumination area is anticipated to be more than minimal until a time period proximal to dawn. In some embodiments peak hours may include time periods when pedestrian and/or vehicular traffic in an illumination area is anticipated to be more than minimal and the ambient light level is less than a predetermined threshold ambient light level. In some embodiments off-peak hours may include one or more time periods between proximal to dusk and proximal to dawn when pedestrian and/or vehicular traffic to an illumination area is anticipated to be minimal. In some embodiments off-peak hours may include one or more time periods when pedestrian and/or vehicular traffic to an illumination area is anticipated to be minimal and the ambient light level is less than a predetermined threshold ambient light level. 
     Referring now to  FIG. 4  a second embodiment of a luminaire  100  having a HID light source and a LED light source is depicted. With reference to  FIG. 4 , the luminaire  100  has a LED arm assembly  120  extending from a vertically extending support pole  105 . Located vertically above the LED arm assembly  120  is a primary HID light source housing coupled to the vertically extending support pole  105  and having an HID lamp therein that selectively produces a primary HID light output. Although the primary HID light source housing is not shown in  FIG. 4 , it is a HID light source housing like HID light source housing  50  of the first embodiment and is coupled to the support pole  105  using a structure other than the LED arm assembly  20 . 
     In alternative embodiments the primary HID light source housing may be any number of housings that encloses an HID lamp and may be alternatively incorporated into the luminaire. For example, in some embodiments of luminaire  100  the HID light source housing may be like HID light source housing  50  of the first embodiment and may be coupled to the support pole  105  using the LED arm assembly  20  of the first embodiment. In other embodiments of luminaire  100 , for example, the HID light source housing may be like HID light source housing  50  of the first embodiment and may be directly coupled to the support pole  5 , or may be coupled to the support pole  5  using support structure other than the LED arm assembly  20 . In other embodiments the HID light source housing may be a cobra head housing. In alternative embodiments the HID light source housing may be located vertically at the same level as the LED arm assembly  120  or below the LED arm assembly  120 . In other embodiments multiple HID light source housings may be provided and/or multiple LED arm assemblies  120  may be provided about a single support pole  105 . 
     The LED arm assembly  120  is similar to the LED arm assembly  20  of the first embodiment. However, the LED arm assembly  120  does not support a HID light source housing and has a front decorative endcap piece  126  in lieu of front attachment piece  27 . In some applications the LED arm assembly  120  may be used in a retrofit situation and coupled to a pole or other support structure proximal a preexisting HID light source housing. The LED arm assembly  120  has an LED light source  140  having a printed circuit board  142  supporting a plurality of LEDs each having a corresponding optical lens  146  thereover. The LED light source  140  is thermally connected to a longitudinally extending heatsink  130  having longitudinally extending lips  133  flanking the printed circuit board  142  and angled heat fins  134  and sidewalls  136  positioned upwardly of the printed circuit board  142 . A cap  122  helps enclose electronics within the LED arm assembly  120  and a rear attachment piece  124  attaches the LED arm assembly  120  to the support pole  105 . 
     In some embodiments the LED arm assembly  120  may enclose a signal receiver controller, a transformer, a HID ballast, and/or a LED driver. Any signal receiving controller internal to LED arm assembly  120  may be in direct or indirect electrical communication with the ballast powering the HID lamp in the HID light source housing of luminaire  100 . The ballast powering the HID lamp may be located in the LED arm assembly  120  in some embodiments and may be located remote from the LED arm assembly  120  in other embodiments. Any signal receiving controller internal to LED arm assembly  120  may also be in direct or indirect electrical communication with the LED driver(s) powering the LED light source  140 . Any signal receiving controller internal to LED arm assembly  120  may be configured to selectively cause either the LED light source  140  or the HID light source of the luminaire  100  to be powered. Any signal receiving controller internal to LED arm assembly  120  may selectively cause either the LED light source  140  or the HID light source of the luminaire  100  to be powered based on a signal sent from a location remote from the luminaire  100 . 
     In some embodiments a plurality of luminaires  10  and/or  100  may form part of a lighting network and be powered by their connection to an external AC power supply and also controlled through their connection to the same external AC power supply. Each transformer  82  of the luminaires  10  and/or  100  may have an AC power supply input electrically connected to the AC power supply and a DC output electrically connected to the signal receiving controller  84 . The signal receiving controller  84  may provide either an above a threshold control output voltage or a below a threshold control output voltage to relays  86 A and  86 B dependent on a control signal received via the DC output from the transformer  82 . Accordingly, the AC power supply will be routed to either the HID ballast  89  or the LED driver  88  dependent on a control signal received via the DC output from the transformer  82 . In some embodiments a lighting controller may be in electrical communication with the AC power supply at a location remote from the plurality of luminaires  10  and/or  100 . The lighting controller may be configured to cause the AC power supply to be pulsingly reduced below a threshold value and restored to at least a threshold value at a predetermined time, thereby causing a control signal to be generated. In some embodiments the AC power supply may be pulsingly removed and restored from the luminaires  10  and/or  100  at a predetermined time, thereby causing a control signal to be generated. Each signal receiving controller  84  of the luminaires  10  and/or  100  may receive the control signal via transformer  82 , recognize the control signal, then either provide at least a threshold voltage to relays  86 A and  86 B or a below a threshold voltage to relays  86 A and  86 B, thereby causing either HID ballast  89  or LED driver  88  to be routed with the AC power supply input. In some embodiments the signal receiving controller  84  may alternate which of at least a threshold voltage and below a threshold voltage it supplies to relays  86 A and  86 B. For example, if the signal receiving controller  84  most recently supplied at least a threshold voltage to relays  86 A and  86 B it may, upon receiving a control signal, supply a below a threshold voltage to relays  86 A and  86 B. In other embodiments the signal receiving controller  84  may supply at least a threshold voltage to relays  86 A and  86 B when a first control signal is received and may supply a below a threshold voltage to relays  86 A and  86 B when a second distinct control signal is received. 
     Optionally, the control signal may be a dual pulse signal, whereby the AC power supplied to the transformer  82  (and the DC power being supplied to the signal receiving controller  84  via transformer  82 ) is reduced below a threshold value for a first removal period, then restored to at least a threshold value for a first restoral period, then reduced below a threshold value for a second removal period, and then restored to at least a threshold value until a next dual pulse signal is sent. Optionally, one or more override switches may be provided that are in electrical communication with the lighting controller and that may be actuated as desired to cause the lighting controller to cause the AC power supply to be pulsingly removed and restored. 
     With reference to  FIG. 6  an embodiment of a lighting network  500  is depicted. The lighting network  500  includes a lighting controller  560  that is in electrical communication with an AC power supply  503 . In some embodiments the AC power supply  503  may be mains power such as, for example, mains 120V AC power. The AC power supply  503  may be a single circuit or may include multiple circuits. In some embodiments the lighting controller  560  is in electrical communication with the AC power supply  503  via a contactor panel which routes the AC power supply  503  therethrough. For example, the lighting controller  560  may be in electrical communication with one or more switches of the contactor panel that each control the flow of the AC power supply  503  to one or more luminaires  10  and/or  100 . The lighting controller  560  is in electrical communication with the transformer  82  of each of a plurality of luminaires  10  via electrical communication with the AC power supply  503 . In some embodiments the lighting controller  560  may additionally or alternatively be in communication with alternative luminaires, such as, for example, one or more luminaires  100 . The lighting controller  560  may be located remote from the plurality of luminaires  10  in some embodiments. For example, the luminaires  10  may be located in a parking lot and the lighting controller  560  may be located in an electrical room of an adjacent building. The lighting controller  560  may be configured for connection to AC power supply  503  in series or parallel therewith. 
     The lighting controller  560  is configured to cause a control pulse signal to be generated via the AC power supply  503  that feeds a plurality of luminaires  10 . In some embodiments the control pulse signal may be generated by the lighting controller  560  causing the AC power supply  503  to be pulsingly removed and restored from the luminaires  10 . The signal receiver controller  84  of each luminaire  10  may be configured to recognize the control pulse signal (via its connection with transformer  82 ) and after recognition of the control pulse signal, cause an alternate of either the HID ballast  89  or the LED driver  88  to be routed with any power that may be supplied by AC power source  503 . The signal receiving controller  84  may provide an alternative of an above a threshold control output voltage or a below a threshold control output voltage to relays  86 A and  86 B when the control signal is received via the DC output from the transformer  82 . Accordingly, any power that may be supplied by AC power source  503  will be routed to either the HID ballast  89  or the LED driver  88 . 
     The lighting controller  560  may be configured to only allow AC power supply  503  to be provided to luminaires  10  at time periods when artificial lighting may be desired. For example, in some embodiments the lighting controller  560  may be coupled to a sensor  564  and may allow power to one or more luminaire  10  when readings from sensor  564  indicate that artificial lighting is desired. For example, in some embodiments the sensor  564  may include one or more photo sensors that measure ambient light levels. In other embodiments, for example, the sensor  564  may additionally or alternatively include one or more motion sensors that may detect when vehicular or pedestrian traffic is present and artificial lighting may be desired. In other embodiments lighting controller  560  may allow power to be supplied to luminaires  10  during one or more predetermined time periods each day. In some embodiments the lighting controller  560  may allow power to be supplied to luminaires  10  at all times during each day. Signal receiving controller  84  of one or more luminaires  10  may in those or other embodiments be optionally paired with a separate time clock or with a sensor and allow power to be supplied to either HID ballast  89  or LED driver  88  only when readings from the lighting controller  560  and the sensor of the luminaires  10  indicate artificial lighting is desired. For example, the signal receiving controller  84  may be in electrical communication with an additional relay interposed between the AC power supply  503  and relays  86 A and  86 B and only allow the relay to be closed when artificial lighting is desired. In other embodiments other devices and/or methods may be used to only allow HID lamp  54  or LED light source  40  to be illuminated at desired periods throughout the day. 
     Optionally, one or more override pushbuttons  562  may be provided in electrical communication with the lighting controller  560  and may be actuated by a user as desired to cause a control pulse signal to be generated, thereby causing each signal receiving controller  84  to cause an alternative of either the HID ballast  84  or the LED drivers  86  to be routed with any power that may be supplied to relays  86 A and  86 B via AC power source  503 . For example, a plurality of luminaire  10  may be provided in a parking lot of a store. Lighting controller  560  may be configured to cause a control pulse signal to be generated each night one hour after the store closes that causes the LED light source  40  to be routed with power and the HID lamp  54  to be extinguished. If the store were to stay open later than normal one night and a user did not want to reprogram the lighting controller  560 , the user could simply actuate the override pushbutton  562  after the LED light source  40  is routed with power to cause the signal receiver controller  84  to cause power to be routed to the HID lamp  54 . Alternatively, or additionally, the override pushbutton  562  may be configured to prevent the lighting controller  560  from causing a pulse signal to be generated when the override pushbutton  562  is in the on or activated position. Thus, using the preceding example, a user could place the override pushbutton  562  in the on or activated position prior to the time when the control pulse signal is typically generated and prevent power from being rerouted from the HID lamp  54  to the LED light source  40 . The override pushbutton  562  could then be moved to the off or non-activated position after the HID light source  54  is no longer needed and the lighting controller  560  may then, or after a period of delay, cause the control pulse signal to be generated. In some embodiments the override pushbutton  562  may be an Allied Electronics AB W411-R. 
     Referring now to  FIG. 7 , a schematic diagram of an embodiment of a method of monitoring for a control signal and alternating between a first light source and a second light source when a control signal is received is provided. The method may be implemented into hardware and/or software of signal receiver controller  84  of each luminaire  10 . At step  690  a voltage input is monitored until a negative edge is detected. The voltage input may be the DC voltage input from transformer  82 . A negative edge is detected when the DC voltage decreases by at least a threshold amount (which corresponds to the root mean square value of the AC voltage being supplied to transformer  82  decreasing by a certain amount). If a negative edge is detected, then at step  692  the voltage input is monitored for a predetermined period of time to determine if a control signal is present at the voltage input. If a control signal is not present at the voltage input then the voltage is monitored again until a negative edge is detected at step  690 . If a control signal is present at the voltage input then at step  694  the AC power source will be routed from a most recently powered light source to a less recently powered light source of a luminaire having two light sources. The AC power source may be routed from a most recently powered light source to a less recently powered light source by altering the state of the control output that feeds relays  86 A and  86 B. After the AC power source has been rerouted, then the voltage is monitored again until a negative edge is detected at step  690 . 
     Referring now to  FIG. 8 , an embodiment of a control signal is graphically depicted. The control signal of  FIG. 8  is a dual pulse control signal and may be caused by lighting controller  560  causing the AC voltage supplied to luminaires  10  to be pulsingly altered, for example, pulsingly removed and restored. The control signal may be received at an AC voltage input of transformer  82  and correspondingly outputted via a DC voltage output of transformer  82 . The horizontal axis in  FIG. 8  represents time in seconds and the vertical axis in  FIG. 8  represents AC voltage. A positive reading on the vertical axis indicates that the root mean square (RMS) of the AC voltage is at or above a threshold RMS voltage and a negative reading on the vertical axis indicates that the RMS of the AC voltage is below a threshold amount. At the time five seconds into this graphical depiction, the RMS of the AC voltage moves from at or above a threshold amount to below a threshold amount. The RMS voltage stays below the threshold for three seconds until a time eight seconds into the graphical depiction, where the RMS voltage moves at or above the threshold amount for three seconds until a time approximately eleven seconds into the graphical depiction. The RMS voltage then moves below the threshold for three seconds until a time fourteen seconds into the graphical depiction, where the RMS voltage moves at or above the threshold amount, where it continues to stay at or above the threshold amount for a predetermined amount of time. The control signal at the DC voltage output of transformer  82  will correspondingly vary between below a threshold DC voltage and at or above a threshold DC voltage. 
     The signal receiver controller  84  may be configured to monitor for the initial negative edge via transformer  82 , then to take a plurality of samples of the voltage output from transformer  82  at predetermined times following the initial negative edge to determine if a control signal is present. For example, the signal receiver controller  84  may be configured to take samples of the voltage output at one, two, four, five, seven, eight, ten, and twelve seconds following the initial negative edge. If the readings at one, two, seven, and eight seconds correspond to a voltage that is less than the threshold voltage amount and the readings at three, four, seven, and eight seconds correspond to a voltage that is at or above a threshold amount, then the signal receiver controller  84  may determine that a control signal is present. In alternative embodiments the signal receiver controller  84  may, for example, take more or less samples, take samples at different frequencies, and/or require that less then all samples correspond to control signal values. 
     Referring now to  FIG. 9 , an embodiment of the lighting controller  560  is depicted in schematic format in additional detail. The lighting controller  560  includes a time clock  570 , a relay  580 , a first power pack  585 , a second power pack  586 , and a signal generating controller  590 . The time clock  570  is a dual channel time clock having a time clock first channel input terminal  571 A and a time clock first channel output terminal  571 B and a time clock second channel input terminal  572 A and a time clock second channel output terminal  572 B. The time clock  570  also has a time clock line terminal  573 A and a time clock neutral terminal  573 B. The time clock line terminal  573 A, the time clock first channel input terminal  571 A, and the time clock second channel input terminal  572 A are electrically coupled to an AC line voltage output  504 . The time clock neutral terminal  573 B is electrically coupled to an AC neutral voltage output  505 . In some embodiments the line voltage output  504  and the neutral voltage output  505  may be routed through a contactor panel which routes an AC power supply therethrough. In some embodiments the time clock  570  may be a Tork EWZ201 digital control. 
     The relay  580  has a relay power terminal  581 , a relay common terminal  582 , a relay neutral terminal  583 , and a relay normally closed output  584 . The relay normally closed output  584  may be electrically coupled to a switch  506  that causes the power to a plurality of luminaires to be applied or removed dependent on the status of the normally closed output  584 . For example, in some embodiments the normally closed output  584  may be electrically coupled to a switch of a contactor panel and may cause the contactor panel to apply power to a plurality of luminaires  10  and/or  100  whenever line voltage is present over the normally closed output  584  and remove power from the plurality of luminaires  10  and/or  100  whenever line voltage is not present over the normally closed output  584 . 
     The first power pack  585  has first power pack AC hot terminals  585 A and  585 F, a first AC power pack neutral terminal  585 B, a first power pack DC hot terminal  585 C, a first power pack DC common terminal  585 D, a first power pack control input terminal  585 E, and first power pack AC hot output terminal  585 G. The second power pack  586  has second power pack AC hot terminals  586 A and  586 F, a second AC power pack neutral terminal  586 B, a second power pack DC hot terminal  586 C, a second power pack DC common terminal  586 D, a second power pack control input terminal  586 E, and second power pack AC hot output terminal  586 G. The first power pack AC hot output terminal  585 G is electrically coupled to the relay common terminal  582 . 
     The signal generating controller  590  has a controller first DC hot input terminal  596 C, a controller first DC common input terminal  596 D, a controller second DC hot input terminal  595 C, a controller second DC common input terminal  595 D, a controller DC control output terminal  595 E, a controller override switch output terminal  592 A and a controller override switch input terminal  592 B. The override switch  562  is coupled between the controller override switch output terminal  592 A and the controller override switch input terminal  592 B. 
     The neutral voltage output  505  is electrically coupled to the first AC power pack neutral terminal  585 B, the second AC power pack neutral terminal  586 B, and the relay neutral terminal  583 . The first power pack AC hot terminals  585 A and  585 F are electrically coupled to the first channel output terminal  571 B. The first power pack DC hot terminal  585 C, first power pack DC common terminal  585 D, and first power pack control input terminal  585 E are electrically coupled to respective of the controller second DC hot input terminal  595 C, controller second DC common input terminal  595 D, and controller DC control output terminal  595 E. 
     The second power pack AC hot terminal  586 A is electrically coupled to the second channel output terminal  572 B. The second power pack DC hot terminal  586 C is electrically coupled to the controller first DC hot input terminal  596 C. The second power pack DC common terminal  586 D is electrically coupled to the controller first DC common input terminal  596 D. 
     In operation, a user may configure the time clock  570  so that the time clock first channel input terminal  571 A is electrically coupled to the time clock first channel output terminal  571 B during preselected times when a user desires power to be supplied to one or more luminaires  10  and/or  100  (e.g., during times of low ambient light and/or during times of high activity). Accordingly, during those times the line voltage output  504  being supplied to the first channel input terminal  571 A will be routed to first power pack hot terminal  585 A, first power pack hot terminal  585 F, and relay power terminal  581 . The relay power terminal  581  will be electrically coupled with the relay normally closed output  584  so long as a threshold voltage is not being received at the relay common terminal  582 . 
     The user may configure the time clock  570  so that the time clock second channel input terminal  572 A is electrically coupled to the time clock second channel output terminal  572 B during preselected times when a user desires a control signal to be generated across the power being supplied to one or more luminaires  10  and/or  100 . Accordingly, during those times the line voltage input  504  being supplied to the second channel input terminal  572 A will be routed to second power pack hot terminal  586 A. Resultantly, second power pack DC hot output terminal  586 C will supply a DC voltage to controller second DC hot input terminal  596 C. When controller second DC hot input terminal  596 C receives a threshold DC voltage, it causes a DC voltage to be pulsingly generated at controller DC control output terminal  595 E, which is then received at first power pack control input terminal  585 E. Whenever the DC voltage is received at first power pack control input terminal  585 E, it causes the line voltage being supplied to first power pack AC hot terminal  585 F to be routed with the first power pack AC hot output terminal  585 G, which is electrically coupled to the relay common terminal  582 . When the line voltage is received at the relay common terminal  582 , the relay power terminal  581  is no longer electrically coupled with the relay normally closed output  584 , thereby causing power to be removed from one or more luminaires  10  and/or  100 . Accordingly, by pulsingly generating a DC voltage at controller DC control output terminal  595 E, power to one or more luminaires  10  and/or  100  is pulsingly removed and restored. 
     The override switch output terminal  592 A may output a DC voltage when DC voltage is being supplied thereto via first power pack DC common terminal  585 D (when time clock first channel input terminal  571 A is electrically coupled to the time clock first channel output terminal  571 B). During such a time, when the override switch  562  is actuated by a user, a threshold DC voltage will be received at the controller override switch input terminal  592 B. When controller override switch input terminal  592 B receives the threshold DC voltage, it causes a DC voltage to be pulsingly generated at controller DC control output terminal  595 E which is then received at first power pack control input terminal  585 E. Accordingly, by pulsingly generating a DC voltage at controller DC control output terminal  595 E, power to one or more luminaires  10  and/or  100  is pulsingly removed and restored. 
     In some applications the control system  500  may be utilized to retrofit an area having a plurality of preexisting HID luminaires with luminaires having an HID light source and an LED light source, wherein neither the plurality of the preexisting HID luminaires nor the luminaires having an HID light source and an LED light source have any separate control wires running thereto. For example, a plurality of preexisting HID luminaires may be provided installed on mounting poles throughout a parking lot having only an AC power source connection. At least one LED arm assembly  120  may be installed on each pole. A transformer  82 , signal receiving controller  84 , and/or relays  86 A and  86 B may be appropriately electrically connected to the electronics driving the LED light source  140  of the LED arm assembly  120 , electrically connected to a ballast powering an adjacent HID lamp, and electrically connected to the AC power source connection. The lighting controller  560  may be installed remote to the luminaires and placed in electrical communication with the AC power source supplying the AC power source connection of each of the luminaires. 
     The foregoing description has been presented for purposes of illustration. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. It is understood that while certain forms of the invention have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims and allowable functional equivalents thereof.