US20100289430A1 - Universal Lighting Source Controller with Integral Power Metering - Google Patents

Abstract

A universal lighting source controller including integral power metering for use with substantially all light source types including fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (“LED”), high density discharge (“HID”), neon, and cold cathode. The lighting source controller includes a line voltage dimming circuit that can control the intensity of light sources in a lighting circuit and measures the actual amount of power consumed by the light sources. The line voltage dimming circuit includes a triac circuit for controlling this intensity and current and voltage detection circuits for measuring the power consumption. The lighting source controller can also include low voltage dimming circuits to provide a control signal to light sources having electronic or magnetic dimming ballasts to set the intensity of these light sources.

Description

TECHNICAL FIELD
• The invention relates generally to lighting source controllers, and more specifically to universal lighting source controllers having integral power metering.
BACKGROUND
• A lighting source controller is an electronic device used to control one or more light sources, such as a fluorescent, incandescent, or light emitting diode (LED) lamp. A lighting source controller activates a light source based on various conditions including occupancy, desired use and time of day. A lighting source controller also controls the intensity of the light source to provide a dimming effect. One of the benefits of lighting control is that dimmed light sources consume less energy than lighting at full load. For this reason, lighting control has been used in various control schemes to reduce demand during peak energy demand times or simply to conserve energy on an ongoing basis.
• Some programs supporting energy conservation, such as the Leader in Energy and Environmental Design (LEED) certification, require validation and measurement of actual energy usage to prove the lighting control systems are realizing reduced energy consumption. To meet this requirement, a separate energy metering system is typically employed to gather the required data. These systems are expensive as they require the design, installation, and maintenance of a second system.
• Therefore, a need currently exists in the art for a lighting source controller that both controls and measures energy usage of light sources without the need for a separate energy metering system.
• Many commercial and industrial buildings utilize more than one type of light source. For example, some buildings employ incandescent, fluorescent, and LED lamps, all in the same building. A conventional lighting source controller typically needs a separate control circuit or control card for each type of light source. This leads to higher costs incurred during the design of the lighting source controller and high maintenance costs for the lighting system. It also requires keeping more spare controller cards readily available, in case one of the controller cards needs replacement. Accordingly, a need also exists in the art for a lighting source controller circuit or controller card capable of controlling multiple types of light sources.
SUMMARY
• The universal lighting source controller can include integral power metering capability for use with substantially all common types of light sources, including fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (LED), high-intensity discharge (HID), neon, and cold cathode.
• The lighting source controller typically includes line voltage dimming cards for controlling and measuring power usage for a lighting circuit having one or more light sources. For example, a lighting control panel can include a single controller for the panel with multiple line voltage dimming cards, each line voltage dimming card controlling and metering energy usage for a lighting circuit with one or more lights. The controller can receive configuration information and control information for each of the dimming cards and communicate this information to the dimming cards. The controller can receive the configuration information from a user interface having a display and input devices. The controller can also receive control information from the user interface or from another device connected to the controller via a network. For example, the controller can be connected to a building management system via a network, such as Ethernet or RS485. This building management system can send commands to the controller to turn lighting circuits on or off and/or set dimming levels for the light sources in the lighting circuits.
• The line voltage dimming cards can include a dimming circuit capable of controlling the intensity level for lights connected to the dimming card. This dimming circuit is universal and can be used with most common light sources, including fluorescent, incandescent, magnetic low voltage, electronic low voltage, LED, HID, neon, and cold cathode. The line voltage dimming card also can include voltage detection circuitry and current detection circuitry. A microprocessor in the line voltage dimming card can receive current and voltage measurements from the current sensor and voltage detection circuitry respectively and calculate the power usage of the lighting circuit controlled by the line voltage dimming card. The microprocessor can then communicate this power usage information to the controller, which in turn can output the power usage information on the user interface.
• The lighting source controller can also include low voltage dimming cards capable of providing a dimming control signal to light sources having electronic or magnetic dimming ballasts. For these light sources, a line voltage dimming card can be used to provide power for the light sources and to measure the power usage of the light sources, while a low voltage dimming card can be used to provide the dimming control. The low voltage dimming card can provide common ballast dimming control signals, including 0-10 VDC, 1-10 VDC, and digital dimming control signals.
• The controller can receive power usage information from each of the line voltage dimming cards and communicate this information to the user interface or to a remote computer for display. The controller can also calculate additional information for display to a user, such as the amount of power being used for each phase of a three phase system and the total amount of power consumed for all circuits connected to the controller.
• These and other aspects, features and embodiments of the invention will become apparent to a person of ordinary skill in the art upon consideration of the following detailed description of illustrated embodiments exemplifying the best mode for carrying out the invention as presently perceived.
BRIEF DESCRIPTION OF THE DRAWINGS
• For a more complete understanding of the exemplary embodiments of the present invention and the advantages thereof, reference is now made to the following description, in conjunction with the accompanying figures briefly described as follows.
• FIG. 1 is a block diagram depicting a universal lighting source controller having integral power metering in accordance with one exemplary embodiment of the present invention.
• FIG. 2 is a block diagram depicting a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIG. 3 is an electrical circuit diagram depicting a zero cross circuit and a voltage detection circuit of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIGS. 4A and 4B are electrical circuit diagrams depicting voltage detection circuits of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIG. 5 is an electrical circuit diagram depicting an analog amplifier circuit of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIG. 6 is an electrical circuit diagram depicting a microprocessor circuit of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIG. 7 is an electrical circuit diagram depicting a surge protection circuit, a relay, a relay drive circuit, and a dimmer circuit of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIG. 8 is an electrical circuit diagram depicting communication circuits and optical isolation circuits of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
• FIG. 9 is an electrical circuit diagram depicting a power supply circuit of a line voltage dimming card in accordance with one exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
• The following description of exemplary embodiments refers to the attached drawings, in which like numerals indicate like elements throughout the figures.FIG. 1 is a block diagram depicting an exemplary universallighting source controller100 having integral power metering in accordance with one exemplary embodiment of the present invention. Thelighting source controller100 controls and meters power usage for substantially all types of light sources, including fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (LED), high-intensity discharge (HID), neon, and cold cathode.
• In this exemplary embodiment, thelighting source controller100 includes apanel controller105 for controlling and metering the power usage of multiple lighting circuits from a single lighting panel (not shown). Thepanel controller105 is in electrical communication with auser interface110, adigital communications module115, one or more linevoltage dimming cards130 and one or more lowvoltage dimming cards140. Thepanel controller105 also receives power from apower supply120 and provides supply power to each of the linevoltage dimming cards130 and each of the lowvoltage dimming cards140.
• Thepanel controller105 receives input from users and provides information to users via theuser interface110. Theuser interface110 can be presented on a variety of displays including a liquid crystal display (LCD), a computer monitor, or a touchscreen. In certain exemplary embodiments, a user configures thepanel controller105, the linevoltage dimming cards130, and the lowvoltage dimming cards140 using input devices, such as a pointing device or keypad coupled to theuser interface110. Theuser interface110 communicates this configuration information to and receives information from thepanel controller105 via various interfaces, including, for example, Ethernet, Universal Serial Bus (USB), and RS485.
• Thedigital communications module115 provides for electrical communication between thepanel controller105 and various other systems or computers via a network. For example, in one exemplary embodiment, thedigital communications module115 includes an Ethernet interface that provides control of light sources from a building management system and provides diagnostics and monitoring capabilities from a remote computer. Other non-limiting examples of communication protocols that can be provided by thedigital communications module115 include RS485 and DMX512 (e.g. control by entertainment systems) serial communication protocols.
• Thelighting source controller100 includes any number of linevoltage dimming cards130 and lowvoltage dimming cards140. Each linevoltage dimming card130 controls and meters the power usage of a lighting circuit having one or more light sources. The linevoltage dimming cards130 are universal and are used with various types of light sources, including fluorescent, incandescent, magnetic low voltage, electronic low voltage, LED, HID, neon, and cold cathode. For example, the same linevoltage dimming card130 can be removed from a lighting circuit of incandescent lights and installed in a lighting circuit of fluorescent lights without any hardware modifications.
• The linevoltage dimming cards130 receive configuration and control information from thepanel controller105 and provide thepanel controller105 with the power usage information for its lighting circuit. In one exemplary embodiment, the configuration information varies based on the lighting supply power and desired control scheme and includes parameters such as a high power limit, low power limit, a setting for turning the lighting source off when input power is below the low power limit or stay on at low limit, and a setting for transient response between the high and low power limits, such as linear, square law, or switched only. The configuration information also includes a setting for scaling the transient response based on the high and low power limits. In one exemplary embodiment, these parameters are received from a user via theuser interface110. Alternatively, the configuration information is received from a remote computer via thedigital communications module115.
• A user programs thepanel controller105 to communicate with the linevoltage dimming cards130 to activate a lighting circuit and control the intensity or dimming of the light sources in the circuit based on various factors, including time of day, occupation of area, desired use, and amount of lighting present in the area. Alternatively, thepanel controller105 receives control information from an outside source, such as a building management system or an entertainment system.
• As discussed in more detail below with reference toFIG. 2, each linevoltage dimming card130 includes a microprocessor for controlling the light sources for its respective lighting circuit. The microprocessor also receives power usage information for the lighting circuit provided by one or more voltage detection circuits and a current detection circuit. This power usage information is communicated to thepanel controller105 and outputted at theuser interface110 and optionally at a remote computer via thedigital communications module115.
• The lowvoltage dimming cards140 provide a dimming control signal to light sources having an electronic or magnetic dimming ballast. Examples of light sources having electronic dimming ballasts include analog fluorescent (2, 3, or 4-wire), LED, and HID dimmable loads. Typically, these electronic dimming ballasts control the intensity level of a light source based on an analog voltage or current range, such as a 0-10 VDC input signal. Additionally, some electronic dimming ballasts control the intensity level of the light source based on a digital signal. The lowvoltage dimming cards140 provide either an analog or digital dimming control signal to the light sources in a lighting circuit.
• Similar to the linevoltage dimming cards130, the lowvoltage dimming cards140 receive configuration and control information from thepanel controller105. The configuration information for the lowvoltage dimming cards140 varies based on the type of ballast and control scheme and includes parameters such as a low voltage high end limit (e.g. 10 VDC), a low voltage low end limit (e.g. 0 VDC), a setting for coordinating the low voltage limit and power switching (e.g. always energized or turn off below low end limit), and a setting for the direction of the low voltage control (i.e. proportional or inverse). Additionally, in certain exemplary embodiments, the configuration information also includes a setting for transient response between the low voltage limits, such as linear, square law, or switched only, and a setting for scaling the transient response according to the high end and low end voltage limits.
• A user programs thepanel controller105 to communicate with the lowvoltage dimming cards140 to control the intensity or dimming of the light sources in the circuit based on various factors, including time of day, occupation of area, desired use of the area, and amount of lighting present in the area. Alternatively, the lowvoltage dimming cards140 receive control information from an outside source, such as a building management system or an entertainment system as discussed above. In one exemplary embodiment, the low voltage dimming cards output a dimming control signal, such as 0-10 VDC, to a lighting circuit based on the desired dimming level.
• The exemplarylighting source controller100 includes a corresponding linevoltage dimming card130 for each lowvoltage dimming card140 used to control light sources having electronic or magnetic dimming ballasts. The corresponding linevoltage dimming card130 provides power for and measures power usage of the light sources, while the lowvoltage diming card140 provides a dimming control signal for adjusting the intensity of the light sources.
• FIG. 2 is a block diagram depicting a linevoltage dimming card130 in accordance with one exemplary embodiment of the present invention. This exemplary linevoltage dimming card130 includes amicroprocessor205 and circuitry for activating, dimming, and measuring power usage of a lighting circuit having one or more light sources. The circuits of the linevoltage dimming card130 are discussed below with reference toFIG. 2 and an exemplary circuit diagram for each circuit is also discussed below with reference toFIGS. 3-9. It should be noted that these circuit diagrams are exemplary and can be modified without departing from the scope and spirit of the invention. It should also be noted that the values for the components in each of the circuit diagrams are also exemplary and can be modified and in some cases, the components can be removed or other components added without departing from the scope or spirit of the invention.
• Referring toFIGS. 1 and 2, themicroprocessor205 receives power from thepanel controller105 via atransformer215 and apower supply217. Thetransformer215 adjusts the voltage level of the input power and thepower supply217 converts the input alternating current (AC) power into direct current (DC) power and provides a steady DC voltage to themicroprocessor205.
• Themicroprocessor205 also receives configuration and control information from thepanel controller105 as described above with reference toFIG. 1. In this exemplary embodiment, thepanel controller105 communicates this information to themicroprocessor205 via aserial communications circuit212, although many other communication protocols are possible as would be known to one or ordinary skill in the art having the benefit of this disclosure. Themicroprocessor205 also utilizes thisserial communications circuit212 to send thepanel controller105 information including power usage information for the lighting circuit that the linecontrol dimming card130 is controlling. Theserial communications circuit212 and themicroprocessor205 are electrically isolated from thepanel controller105 by anoptical isolation circuit210.
• The line voltagedimming control card130 receives power for its lighting circuit from ahot power line221 and aneutral power line222 and outputs power onto three separate power lines, alive power line280, a switchedpower line285 and a dimmedpower line290 depending on the configuration of the lighting circuit. For example, if light dimming is not desired, the linevoltage dimming card130 is used to switch the light sources on and off. In this example, the lighting circuit is connected to the switchedpower line285. If dimming is desired, the lighting circuit is connected to the dimmedpower line290. Additionally, the livevoltage power line280 is provided for an emergency non-switched lighting connection.
• The linevoltage dimming card130 includes asurge protection circuit225 for diverting or suppressing a spike in input voltage. In one exemplary embodiment, thesurge protection circuit225 is positioned near the entry point of the input voltage to protect other circuits in the linevoltage dimming card130. Various types ofsurge protection circuits225 can be used with the linevoltage dimming card130, including metal oxide varistor circuits and suppression diode circuits.
• The linevoltage dimming card130 also includes a zerocross circuit230 for detecting transitions between positive and negative voltage levels of the input AC voltage. At each transition, the zerocross circuit230 provides a short electrical pulse to themicroprocessor205. This series of pulses resembles a square wave signal which is used by themicroprocessor205 to time the energizing and de-energizing of the light sources in a dimming application.
• Acurrent sensor235 and ananalog amplifier237 are provided with the linevoltage dimming card130 to measure the current flow through the linevoltage dimming card130 and thus, through the lighting circuit it controls. This current measurement is taken along thehot power line221 and is provided to themicroprocessor205.
• This exemplary linevoltage dimming card130 also includes three separatevoltage detection circuits240,250,260. Thevoltage detection circuit240 measures the voltage level across thelive voltage point280 and theneutral power line222. Thevoltage detection circuit250 measures the switched output voltage level across the switchedpoint285 and theneutral power line222 downstream from arelay247. Thevoltage detection circuit260 measures the dimmed voltage level across the dimmedpoint290 and theneutral power line222. In one exemplary embodiment, eachvoltage detection circuit240,250,260 provides themicroprocessor205 with its respective voltage measurement.
• Themicroprocessor205 determines the amount of power that its lighting circuit is consuming using the current measurement provided by thecurrent sensor235 and a voltage measurement from one of thevoltage detection circuits240,250,260 depending on the configuration or application of the linevoltage dimming card130. For example, if the linevoltage dimming card130 is used in a dimming application, themicroprocessor205 uses the voltage measurement from thevoltage detection circuit260. In an alternative exemplary embodiment when the linevoltage dimming card130 is used in a switched (non-dimming) application, the voltage measurement from thevoltage detection circuit250 is used. Additionally, in emergency lighting applications, the voltage measurement from thevoltage detection circuit240 is used. Themicroprocessor205 communicates this power calculation to thepanel controller105 for display at theuser interface110 or at a remote computer via thedigital communications module115.
• The linevoltage dimming card130 includes arelay247 for passing or blocking electrical power along thehot power line221 to the light sources of the lighting circuit. Themicroprocessor205 activates therelay247 to energize the lighting loads by sending a control signal to arelay drive245, which in turn energizes a coil in therelay247. Although arelay247 is utilized in this exemplary embodiment, other suitable switching devices can be used as would be known by one of ordinary skill in the art having the benefit of the present disclosure.
• The linevoltage dimming card130 also includes a dimming circuit having a dimmer257, adimmer drive255, and aninductor265. In one exemplary embodiment, for light sources that do not have an electronic or magnetic dimming ballast, themicroprocessor205 sends electrical signals to thedimmer drive255, which in turn, controls the dimmer to provide a dimming level to light sources based on control information received from thepanel controller105. As discussed in more detail below with reference toFIG. 7, the dimmer257 includes a triac that is activated and deactivated at high frequencies to turn the light sources on and off at a high frequency. This reduces the total amount of energy delivered to the light sources and therefore, reduces the intensity of the light. This dimming level is adjusted by changing the frequency of the activation of the triac in the dimmer257. In one exemplary embodiment, the timing of the activation and deactivation of the triac is synchronized with the zero cross signal by themicroprocessor205.
• FIG. 3 is an electrical circuit diagram depicting an exemplary zerocross circuit230 and an exemplaryvoltage detection circuit240 of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. An operational amplifier (“op-amp”) IC1A receives AC voltage across the hot221 and neutral222 lines of a lighting circuit and provides a scaled AC signal to the zerocross circuit230 and thevoltage detection circuit240. In this exemplary embodiment, the op-amp IC1A and its associated circuitry works to scale the input AC signal to an output range of 0-5 VAC. A reference voltage REF_V of 2.5 VAC is provided at the non-inverting input of the op-amp IC1A to provide a bias voltage at the midrange of the scaled output range.
• The zerocross circuit230 converts the AC signal to a square-wave signal PROC_SQ with peaks corresponding to transitions of the AC signal through zero volts. This square wave signal PROC_SQ is transferred to an input of themicroprocessor205 for use in timing the activation and deactivation of light sources in a dimming application. This exemplary zerocross circuit230 includes an op-amp IC1B, two inverting Schmitt triggers IC2A, IC2B connected in series at the output of the op-amp IC1B, and associated resistors and capacitors. Exemplary values for the components of the zero-cross circuit230 and for components associated with op-amp IC1A are listed below in Table 1.

• TABLE 1
  Exemplary Component Values for theZero Cross Circuit
  230 and Components Associated with Op-Amp IC1A

  	Circuit Component	Value

  	R1	4.7	kΩ
  	R2	990	kΩ
  	R3	990	kΩ
  	R4	4.7	kΩ
  	R5	100	kΩ
  	R6	1	MΩ
  	R7
  	10	kΩ

• Thevoltage detection circuit240 scales the AC signal received from the op-amp IC1A and provides this scaled signal PROC_LIVE to themicroprocessor205. Themicroprocessor205 can then compare this scaled signal PROC_LIVE to a reference voltage to calculate the actual voltage between the liveoutput power line280 and theneutral power line222. This exemplaryvoltage detection circuit240 includes an op-amp IC1D, and associated resistors and capacitors. Thevoltage detection circuit240 also includes a network of diodes and capacitors at the output of the op-amp IC1D for protecting themicroprocessor205 from voltage ranges above or below the scaled range of 0-5 VAC. Exemplary values for the components of thevoltage detection circuit240 are listed below in Table 2.

• TABLE 2
  Exemplary Component Values for the
  Voltage Detection Circuit 240

  	Circuit Component	Value

  	R8	39	kΩ
  	R9	82	kΩ
  	R10	1	kΩ
  	R11	100	kΩ
  	C1	1	nF
  	C2	1	nF
  	C3	100	nF

• FIGS. 4A and 4B, collectivelyFIG. 4, are electrical circuit diagrams depicting exemplaryvoltage detection circuits250,260 of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. Referring toFIG. 4A, thevoltage detection circuit250 scales the AC signal received across the switchedoutput power line285 and theneutral power line222 and provides this scaled signal PROC_SWITCHED to themicroprocessor205. Themicroprocessor205 compares this scaled signal PROC_SWITCHED to a reference voltage to determine the actual voltage between the switchedoutput power line285 and theneutral power line222. This exemplaryvoltage detection circuit250 includes an op-amp IC3A, and associated resistors and capacitors. Thevoltage detection circuit250 also includes a network of diodes and capacitors at the output of the op-amp IC3A for protecting themicroprocessor205 from voltage ranges above or below the scaled range of 0-5 VAC. Exemplary values for the components of thevoltage detection circuit250 are listed below in Table 3.

• TABLE 3
  Exemplary Component Values for the
  Voltage Detection Circuit 250

  	Circuit Component	Value

  	R1	4.7	kΩ
  	R2	990	kΩ
  	R3	990	kΩ
  	R4	1	kΩ
  	R5	4.7	kΩ
  	C1	100	nF

• Referring toFIG. 4B, the exemplaryvoltage detection circuit260 scales the AC signal received across the dimmedoutput power line290 and theneutral power line222 and provides this scaled signal PROC_DIMMED to themicroprocessor205. Themicroprocessor205 compares this scaled signal PROC_DIMMED to a reference voltage to calculate the actual voltage between the dimmedoutput power line290 and theneutral power line222. This exemplaryvoltage detection circuit260 includes an op-amp IC3B, and associated resistors and capacitors. Thevoltage detection circuit260 also includes a network of diodes and capacitors at the output of the op-amp IC3B for protecting themicroprocessor205 from voltage ranges above or below the scaled range of 0-5 VAC. Exemplary values for the components of thevoltage detection circuit260 are listed below in Table 4.

• TABLE 4
  Exemplary Component Values for the
  Voltage Detection Circuit 260

  	Circuit Component	Value

  	R6	4.7	kΩ
  	R7	990	kΩ
  	R8	990	kΩ
  	R9	1	kΩ
  	R10	4.7	kΩ
  	C2	100	nF

• FIG. 5 is an electrical circuit diagram depicting an exemplaryanalog amplifier circuit237 of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. This exemplaryanalog amplifier circuit237 includes an op-amp IC3C which scales a voltage measurement taken across a current sensing resistor R44 (SeeFIG. 7). This voltage measurement is scaled by the op-amp IC3C and this scaled signal PROC_IM is transmitted to themicroprocessor205. Themicroprocessor205 compares the scaled signal PROC_IM to a reference voltage to determine the current flowing through the resistor R44 and thus through the lighting circuit that the linevoltage dimming card130 controls. Exemplary values for the components of theanalog amplifier circuit237 are listed below in Table 5.

• TABLE 5
  Exemplary Component Values for the
  Analog Amplifier Circuit 237

  	CircuitComponent	Value

  R1

  	10	kΩ
  	R2	150	kΩ
  	R3	1	kΩ
  	R4	150	kΩ
  	R5	10	kΩ
  	C1	100	nF

• FIG. 6 is an electrical circuit diagram depicting anexemplary microprocessor205 circuit of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. In one exemplary embodiment, themicroprocessor205 includes 16 pins for sending or receiving electrical signals. A description of the signal at each pin of themicroprocessor205 is described below in Table 6. Thisexemplary microprocessor205 circuit includes a light emitting diode (LED) LD1, aclock circuit605, and associated resistors and capacitors. Thisclock circuit605 employs a crystal oscillator X1 to provide a reference clock signal to themicroprocessor205. Exemplary values for the components of themicroprocessor circuit205 are listed below in Table 7.

• TABLE 6
  Microprocessor 205 Input/Output Pins

  Pin Number	Description

  1	Status indication.
  2	Receives voltage measurement signal PROC_DIMMED
  	from thevoltage detection circuit 260.
  3	Receives voltage measurement signal PROC_LIVE
  	from thevoltage detection circuit 240.
  4	0 V input.
  5	+5 V input.
  6	Receives square-wave output signal PROC_SC from
  	the zerocross circuit 230.
  7	Not used.
  8	Receives clock input signal from oscillator X1.
  9	Receives clock input signal from oscillator X1.
  10	Outputs a communication signal to theserial
  	communications circuit
  212.
  11	Receives a communication signal from theserial
  	communications circuit
  212.
  12	Outputs signal to operate therelay 247.
  13	Not used.
  14	Receives voltage measurement signal PROC_IM
  	from theanalog amplifier circuit 237.
  15	Receives voltage measurement signal PROC_SWITCHED
  	from thevoltage detection circuit 250.
  16	Sends dimming control signal to thedimmer
  	drive circuit
  255.

• TABLE 7
  Exemplary Component Values for theMicroprocessor 205 Circuit

  	Circuit Component	Value

  	R1	330	Ω
  	R2	4.7	MΩ
  	R3
  	10	kΩ
  	C1	22	pF
  	C2	22	pF

• FIG. 7 is an electrical circuit diagram depicting examples of asurge protection circuit225, arelay247, arelay drive circuit245, adimmer drive circuit255, and atriac dimmer257 of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. Thehot power line221 and the neutral power line are connected to the linevoltage dimming card130 at connectors CON1 and CON2 respectively. Theoutput power lines280,285, and290 are connected to connector CON3 to receive power for a light source.
• Thesurge protection circuit225 includes a capacitor C9 and a varistor V1. The varistor V1 acts to divert any voltage surges present along thehot line221 in order to protect the circuitry in the linevoltage dimming card130.
• Therelay drive circuit245 includes a field effect transistor (FET) Q2 for controlling therelay247. Therelay drive circuit245 receives a control signal PROC_RLDR from themicroprocessor205 and opens or closes therelay247 based on this control signal PROC_RLDR. The control signal PROC_RLDR is applied to thebase1 of the FET Q2 which allows current flow through a channel betweenpoints2 and3 of the FET Q2 when the PROC_RLDR signal is above a threshold voltage. This flow of current drives a coil inrelay247 to close. In one exemplary embodiment, without this flow of current, therelay247 remains open.
• Thedimmer drive circuit255 includes an optoisolator triac driver IC8, two resistors R5, R7, and a capacitor C2. The triac driver IC8 receives a dimmer controller signal OPTO_TRIAC from themicroprocessor205. Based on the dimmer control signal OPTO_TRIAC, the triac driver IC8 energizes the dimmer257 to allow current to flow from the switchedoutput power line285 through the dimmer257, through aninductor265, and to the dimmedoutput power line290 at CON3. As thetriac dimmer257 and theinductor265 can be large devices, in a panel embodiment, thesedevices257,265 can be mounted external from the line dimmingvoltage card130. Exemplary values for the components of thesurge protection circuit225, therelay drive circuit245, and thedimmer drive circuit255 are listed below in Table 8.

• TABLE 8
  Exemplary Component Values for theSurge Protection Circuit 225,
  theRelay Drive Circuit 255, and theDimmer Drive Circuit 255

  	CircuitComponent	Value

  R1

  1

  MΩ

  R2 (thermistor)

  Variable proportional totemperature

  R3

  	1	MΩ
  	R4
  	1	MΩ

  	R5 (thermistor)	Variable proportional to temperature
  	R6 (thermistor)	Variable proportional to temperature
  	R7 (thermistor)	Variable proportional totemperature

  C1

  	1	μF
  	C2
  	100	nF

• FIG. 8 is an electrical circuit diagram depicting exemplary serial communication circuits212-1,212-2 and exemplary optical isolation circuits210-1,210-2 of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. The exemplary serial communication circuits212-1 and212-2 provide serial communications between themicroprocessor205 and thepanel controller105.
• The serial communication circuit212-1 receives a serial communication signal TX_OC at connector CON1 and transfers the signal TX_OC to the optical isolation circuit210-1, which in turn transfers a representative signal PROC_RX to themicroprocessor205. The optical isolation circuit210-1 includes an optocoupler IC6 which provides electrical isolation between thepanel controller105 and themicroprocessor205 for the serial communication signals PROC_RX and TX_OC. The serial communications circuit212-1 and the optical isolation circuit210-1 includes two capacitors C20, C40 and three resistors R52, R54, R63.
• The serial communication circuit212-2 receives a serial communication signal PROC_TX from themicroprocessor205 and transfers the signal PROC_TX to the optical isolation circuit210-2 which in turn transfers a representative signal TX_OC to thepanel controller105. The optical isolation circuit210-2 includes an optocoupler IC7 which provides electrical isolation between thepanel controller105 and themicroprocessor205 for the serial communication signals PROC_TX and TX_OC. The serial communications circuit212-2 and optical isolation circuit includes a capacitor C21 and three resistors R55, R61, R62. Exemplary values for the components of the serial communication circuits212-1,212-1 and the optical isolation circuits210-1,210-2 are listed below in Table 9.

• TABLE 9
  Exemplary Component Values for the Serial Communication Circuits
  212-1, 212-2, and the Optical Isolation Circuits 210-1 and 210-2

  	Circuit Component	Value
  	R1 (thermistor)	Variable proportional to temperature
  	R2 (thermistor)	Variable proportional to temperature

  R3

  3.3

  kΩ

  	R4 (thermistor)	Variable proportional to temperature
  	R5 (thermistor)	Variable proportional to temperature
  	R6 (thermistor)	Variable proportional totemperature

  C1

  	100	nF
  	C2	100	nF
  	C3	47	μF

• FIG. 9 is an electrical circuit diagram depicting examples of atransformer215 and apower supply circuit217 of a linevoltage dimming card130 in accordance with the exemplary embodiment ofFIG. 2. In this exemplary embodiment, thetransformer215 receives AC power from the panel controller105 (SeeFIG. 1) and steps the input voltage down to an appropriate voltage level for thepower supply circuit217. Thepower supply circuit217 receives the stepped down voltage from thetransformer215 and employs a voltage regulator IC5 to provide a steady DC voltage to themicroprocessor205. This exemplarypower supply circuit217 includes a rectifier circuit having four diodes D9, D10, D11, D12 connected across the secondary winding of thetransformer215. This rectifier circuit converts the AC voltage received on the secondary windings of thetransformer215 into a DC voltage. Thepower supply circuit217 also includes associated inductors, resistors, capacitors, and a diode D8. Exemplary values for the components of thepower supply circuit217 are listed below in Table 10.

• TABLE 10
  Exemplary Component Values for thePower Supply Circuit 217

  	CircuitComponent	Value

  C1

  	100	nF
  	C2	47	μF
  	C3
  	100	nF
  	C4	47	μF
  	C5
  	100	nF
  	L1	22	μH
  	L2	22	μH

• Although specific embodiments of the invention have been described above in detail, the description is merely for purposes of illustration. It should be appreciated, therefore, that many aspects of the invention were described above by way of example only and are not intended as required or essential elements of the invention unless explicitly stated otherwise. Various modifications of, and equivalent steps corresponding to, the disclosed aspects of the exemplary embodiments, in addition to those described above, can be made by a person of ordinary skill in the art, having the benefit of this disclosure, without departing from the spirit and scope of the invention defined in the following claims, the scope of which is to be accorded the broadest interpretation so as to encompass such modifications and equivalent structures.

Claims (32)

1. A lighting control system, comprising:

a lighting control circuit operable to receive a control signal comprising a command to energize a light source and allow electrical energy to flow to the light source in response to the command; and

a controller communicably coupled to the lighting control circuit, the controller operable to transmit the control signal to the control circuit,

wherein the lighting control circuit is electrically coupled to the light source, and

wherein the lighting control circuit is operable for use with at least two of fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (LED), high intensity discharge (HID), neon, and cold cathode light sources.

2. The lighting control system ofclaim 1, wherein the lighting control circuit comprises a microprocessor operable to receive the control signal and transmit an electrical signal allowing the flow of electrical energy to the light source in response to the command.

3. The lighting control system ofclaim 1, wherein the control signal further comprises an intensity setting for the light source.

4. The lighting control system ofclaim 3, wherein the lighting control circuit adjusts the intensity level of the light source by sequentially allowing and blocking the flow of electrical energy to the light source at a frequency.

5. The lighting control system ofclaim 4, wherein the control circuit comprises a triac operable to sequentially allow and block the flow of electrical energy to the light source at the frequency.

6. The lighting control system ofclaim 1, wherein the lighting control circuit further comprises a power metering circuit, wherein the power metering circuit measures an amount of electrical energy used by the light source.

7. The lighting control system ofclaim 6, wherein the power metering circuit comprises:

at least one voltage detection circuit; and

a current measurement circuit.

8. The lighting control system ofclaim 7, further comprising a user interface communicably coupled to the controller, wherein the controller transmits a representation of the amount of electrical energy used by the light source to the user interface for outputting to a user.

9. The lighting control system ofclaim 1, wherein the light source comprises an electronic dimming ballast.

10. The lighting control system ofclaim 9, further comprising a low voltage dimming circuit communicably coupled to the electronic dimming ballast and operable to transmit a dimming level signal to the electronic dimming ballast, wherein the command comprises an intensity setting for the light source and wherein the dimming level signal corresponds to the intensity setting.

11. The lighting control system ofclaim 10, wherein the dimming level signal comprises a variable analog voltage level.

12. The lighting control system ofclaim 10, wherein the dimming level signal comprises a digital signal.

13. A lighting circuit control card for use with a plurality of types of lighting sources, comprising:

a control circuit, electrically coupled to at least one light source, the control circuit operable to receive a control signal comprising an indication that the at least one light source should be energized and operable to permit electrical energy to flow to the at least one light source in response to the indication; and

a power metering circuit operable to determine an amount of electrical power consumed by the at least one light source.

14. The lighting circuit control card ofclaim 13, wherein the plurality of types of lighting sources comprise at least two of fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (“LED”), high density discharge (“HID”), neon, and cold cathode light sources.

15. The lighting circuit control card ofclaim 13, wherein the power metering circuit comprises:

at least one voltage detection circuit; and

a current detection circuit.

16. The lighting circuit control card ofclaim 13, wherein the control signal further comprises a desired intensity level and wherein the control circuit adjusts an intensity level of the at least one light source based on the desired intensity level.

17. The lighting circuit control card ofclaim 16, wherein the control circuit adjusts the intensity level of the at least one light source by sequentially allowing and blocking the flow of electrical energy to the at least one lighting source.

18. The lighting circuit control card ofclaim 17, wherein the control circuit further comprises a triac, wherein the triac sequentially allows and blocks the flow of electrical energy to the at least one light source at a frequency.

19. A method for controlling a light source, the method comprising the steps of:

receiving a control signal at a lighting control circuit, the control signal comprising a command to energize the light source and a desired intensity level for the light source;

in response to receiving the control signal, allowing, by the lighting control circuit, electrical energy to flow to the light source; and

measuring, by the lighting control circuit, an amount of electrical energy used by the light source,

wherein the lighting control circuit is operable for use with at least two of fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (“LED”), high density discharge (“HID”), neon, and cold cathode light sources.

20. The method ofclaim 19, wherein the step of allowing electrical energy to flow to the light source comprises sequentially allowing and blocking the flow of electrical energy to the light source at a frequency corresponding to the desired intensity level.

21. The method ofclaim 20, wherein the lighting control circuit comprises a microprocessor and a triac and wherein the triac receives a signal from the microprocessor and in response to the signal, the trial allows electrical energy to flow to the light source for a period of time corresponding to the frequency.

22. The method ofclaim 19, further comprising the step of transmitting a representation of the amount of electrical energy used by the light source to a user interface for outputting to a user.

23. The method ofclaim 19, further comprising the step of receiving the control signal at a panel controller from a source external to the panel controller and the lighting control circuit, wherein the control signal is received from the panel controller.

24. The method ofclaim 23, wherein the source external to the panel controller and the lighting source comprises a building management system.

25. The method ofclaim 19, further comprising the step of receiving configuration information for the lighting control circuit.

26. The method ofclaim 25, wherein the configuration information comprises a high power limit and a low power limit for the lighting source.

27. A lighting system, comprising:

a lighting controller operable to send control signals to line voltage dimming cards;

one or more line voltage dimming cards communicably coupled to the lighting controller, each line voltage dimming card comprising:

a control circuit, electrically coupled to a lighting circuit comprising at least one light source, the control circuit operable to receive a control signal comprising an indication that the at least one light source should be energized and a desired intensity level for the at least one light source, the control circuit further operable to permit electrical energy to flow to the at least one light source in response to the indication and control an intensity level of the at least one light source in response to the desired intensity level; and

a power metering circuit operable to determine an amount of electrical power consumed by the at least one light source in the lighting circuit; and

a user interface communicably coupled to the lighting controller and operable to receive configuration information for the panel controller and the one or more line voltage dimming cards and further operable to output a representation of the amount of electrical power consumed by the at least one light source from the lighting controller,

wherein each of the line voltage dimming cards is operable for use with at least two of fluorescent, incandescent, magnetic low voltage, electronic low voltage, light emitting diode (“LED”), high density discharge (“HID”), neon, and cold cathode light sources.

28. The lighting system ofclaim 27, wherein the lighting controller is further operable to receive control signals from a controller via a network.

29. The lighting system ofclaim 27, further comprising one or more low voltage dimming cards communicably coupled to the lighting controller, each line voltage dimming card operable to transmit a dimming control signal corresponding to the desired intensity level to a light source having an electronic dimming ballast.

30. The lighting system ofclaim 27, wherein the control circuit controls the intensity level of the at least one light source by energizing and de-energizing the at least one light source at a frequency corresponding to the desired intensity level.

31. The lighting system ofclaim 30, wherein the control circuit comprises a zero cross circuit for timing the energizing and de-energizing of the at least one light source.

32. The lighting system ofclaim 27, wherein each of the line voltage dimming cards is operable for use with each of fluorescent, incandescent, and LED light sources without modification to any hardware of the line voltage dimming card.

Images