Patent Publication Number: US-2017354007-A1

Title: Temperature correction for energy measurement in a street lighting luminaire

Description:
FIELD 
     The aspects of the present disclosure relate generally to street lighting fixtures. In particular, the aspects of the disclosed embodiments are directed to energy measurement in a street lighting fixture. 
     BACKGROUND 
     Street lighting lamps or luminaires are generally designed for long life operation. The typical street lamp will generally include a weather proof, robust, cast aluminium housing that is mounted on a pole. The lighting components, such as a light source, electrical driver, other optics, electrical components and devices are incorporated into the aluminium housing. As the street lamp is typically outdoors, the street lamp and the components within the housing will be subjected to a variety of environmental conditions, such as variations in temperature. 
     In an uncontrolled or unregulated environment, the street lamp and the components within the interior of the housing of the street lamp can be subject to a range of different temperatures. Example of these temperatures can range from approximately −40 degrees Celsius to and including approximately +50 degrees Celsius. In some cases, temperatures as high as +85 degrees Celsius have been realized. This temperature range is merely exemplary, and it will be understood that the different environments where a street lamp can be used and is located will vary in terms of temperature. 
     Electronic components and device, such as LEDs and LED drivers, and the performance of these components, can be affected by changes in temperature. Electronic devices are generally configured to provide a certain level of performance or output at predetermined temperatures or temperature ranges. For example, with respect to an LED, the cooler the environment, the higher the light output of the LED will tend to be. At higher temperatures, the light output of the LED tends to be reduced. Further, in warmer environments and at higher currents, the temperature of the semiconducting element of the LED tends to increases. The light output of an LED for a constant current will tend to vary as a function of its junction temperature. 
     The measurement of the electrical performance of an LED lamp, such as a street lamp, will tend to vary as a function of the temperature of the environment within which the LED lamp is operating. Measurement variables such as current, voltage, active power, reactive power and energy will be dependent upon the temperature of the environment within which the LED lamp(s) is operating. The environmental temperature impacts the operational temperature and performance of an LED lamp. It would be advantageous to be able to minimize and/or remove the effects of temperature and temperature offset in the measurement of the performance of a street lamp. 
     Accordingly, it would be desirable to provide an LED street lighting assembly that addresses at least some of the problems identified above. 
     SUMMARY 
     As described herein, the exemplary embodiments overcome one or more of the above or other disadvantages known in the art. One aspect of the exemplary embodiments relates to a street lighting assembly. In one embodiment, the street lighting assembly. The street lighting assembly includes an LED lighting device and a node assembly coupled to the LED light device. The node assembly includes a processor, the processor being configured to detect a temperature within an operating environment of the LED light device, determine a correction factor associated with the detected temperature, apply the correction factor to one or more measured values of electrical parameters of the LED light device and adjust the one or measured values of electrical parameters of the LED light device for an offset based on temperature. 
     Another aspect of the exemplary embodiments relates to a method. In one embodiment, the method includes determining a temperature of an operating environment for an electronic device; measuring one or more electrical parameters associated with an operation of the electronic device in the operating environment; and using a processor to execute machine readable instructions stored in a memory device, the machine readable instructions when executed by the processor being configured to cause the processor to: determine a correction factor associated with the determined temperature; and apply the determined correction factor to the one or more electrical parameters associated with the operation of the electronic device in the operating environment to adjust the measured electrical parameters for a temperature offset. 
     These and other aspects and advantages of the exemplary embodiments will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. Additional aspects and advantages of the invention will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. Moreover, the aspects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate presently preferred embodiments of the present disclosure, and together with the general description given above and the detailed description given below, serve to explain the principles of the present disclosure. As shown throughout the drawings, like reference numerals designate like or corresponding parts. 
         FIG. 1  illustrates an exemplary street light assembly incorporating aspects of the disclosed embodiments. 
         FIG. 2  is a flowchart illustrating a process incorporating aspects of the disclosed embodiments. 
         FIG. 3  is another exemplary street light assembly incorporating aspects of the disclosed embodiments. 
         FIG. 4  illustrates an exemplary circuit board for a street light assembly incorporating aspects of the disclosed embodiments. 
         FIG. 5  is a flow chart of an exemplary process incorporating aspects of the disclosed embodiments. 
         FIG. 6  is an exemplary curve of energy measurement error as a function of temperature. 
         FIG. 7  illustrates an exemplary corrector function for a street lighting assembly incorporating aspects of the disclosed embodiments. 
         FIG. 8  is an exemplary node assembly for a street light assembly incorporating aspects of the disclosed embodiments. 
         FIG. 9  illustrates an exemplary wireless control system for street and roadway light assemblies incorporating aspects of the disclosed embodiments. 
         FIG. 10  illustrates another example of a node assembly for a street light assembly incorporating aspects of the disclosed embodiments. 
         FIG. 11  illustrates an exemplary architecture that can be used to practice aspects of the disclosed embodiments. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS OF THE DISCLOSURE 
       FIG. 1  illustrates one embodiment of a street light or lamp assembly  100  including aspects of the disclosed embodiments. The aspects of the disclosed embodiments are generally directed to correcting for the effects that the temperature of the environment in which an electrical device or component is located has on the measurement of one or more electrical performance parameters of the device. The aspects of the disclosed embodiments will generally be described herein with respect to a street light assembly, such as for example an LED street light assembly. By correcting for the effect that the temperature of the environment where the LED street light assembly is located has on measured electrical performance parameters, improved accuracy can be realized in the measuring the performance of the LED street light assembly. 
     Although the aspects of the disclosed embodiments are described herein with respect to a street light assembly, the aspects of the disclosed embodiments are not so limited. The aspects of the disclosed embodiments can be applied to any electrically powered or electronic equipment, generally referred to herein as a “device” or “equipment”, where the ambient temperature of the environment where the device is located can have an effect on the measurement, or measurement results, of electrical performance parameters such as current, voltage, power and energy. 
     In the example of  FIG. 1 , the exemplary street light assembly  100  generally includes a light or lamp assembly  110 , a housing  120 , and a pole  130 . In the example of  FIG. 1 , the light assembly  110  and housing  120  are coupled to the pole  130 . Although the aspects of the disclosed embodiments are generally described herein with respect to the light assembly  110  being mounted on a pole  130 , the aspects of the disclosed embodiments are not so limited. The pole  130  is configured to secure the light assembly  100  in place, such as in the ground or a stationary structure such as a wall or post member. In alternate embodiments, the light assembly  110  can be mounted to any suitable structure, such as a building, for example, without a pole member  130 . 
     In one embodiment, the light assembly  110 , which may also be referred to as a luminaire, is disposed or contained within the housing  120 . As is illustrated in  FIG. 1 , in one embodiment, the light assembly  110  includes or is coupled to a modular connector unit  140 . The modular connector unit  140  is used to couple or connect at least a light portion  160  of the light assembly  110  to the pole  130 , depending on the particular configuration. The modular connector unit  140  can include the electrical connection from the mains power to provide electrical power to the light assembly  110 . 
     The light assembly  110  includes a light portion  160 . The light portion  160  generally comprises or includes an LED light or LED lighting assembly, also referred to as an LED module. The LED module will generally be understood to include or provide the electrical power and signalling to activate the light portion  160 . For the purposes of the description herein, the light portion  160  will generally include the electronic components and devices that are typically associated with an LED luminaire. These components can include, for example, but are not limited to, an LED light cluster (comprising one or more LEDs) assembled to or sealed on one or more of a circuit board panel, a heat sink, and an LED driver or power supply. The light portion  160 , and the electrical components associated therewith, will generally be disposed within the housing  120 . 
     As will be understood, during a typical operation, the environment outside the housing  120  can be at one temperature, while the temperature inside the housing  120  can be at another temperature. The aspects of the disclosed embodiments are configured to determine the temperature of the environment in which the light portion  160  is operating, and provide a correction factor to be applied to the results of the measurement of electrical performance parameters of the light portion  160  to remove any offset introduced into the measurement results. The electrical parameters that are measured can include but are not limited to, current voltage, active power, reactive power and energy. The measurement of these exemplary parameters is dependent upon the temperature of the environment and will be affected whenever the digital system, in this case the light assembly  100 , operates in an outdoor environment. By correcting for temperature, more accurate electrical performance and measurement results in such a digital system can be provided. 
       FIG. 2  illustrates an exemplary process incorporating aspects of the disclosed embodiments. In one embodiment, the temperature of the environment in which the device, such as the street light assembly  100 , is operating is determined  202 . Generally, as will be described further herein, with respect to the street light assembly  100 , the temperature within the housing  120  in which the various electronic components of the light portion  160  are disposed is determined  202 . In one embodiment, as will be described further herein, the electronic components comprise digital electronic components. 
     For example, in the case of the street light assembly  100  referenced in  FIG. 1 , the street light assembly  100  is typically operating in an outdoor environment. As noted above, the temperature of the environment in which the street light assembly  100  is operating can range from approximately −40 degrees Celsius to and including +85 degrees Celsius. When electrical parameters such as current, voltage and power of the street light assembly  100  are measured, the results can be affected by the environmental temperature. 
     In one embodiment, once the temperature is determined  202 , a correction factor or offset related to the determined temperature is determined  204 . The correction factor is then applied  206  to the measured values. In one embodiment, applying the correction factor comprises using a digital corrector device to apply a non-linear correction algorithm to the measurement results. In this manner, the aspects of the disclosed embodiments correct for the effect of temperature on measured values related to the performance and output of a device such as the street light assembly generally disclosed herein. 
       FIG. 3  illustrates another example of an exemplary street light assembly  300  incorporating aspects of the disclosed embodiments. In this example, the street light  300  includes a node assembly  310  that is disposed on the housing  120 . As will be described further below, the node assembly  310  is generally configured to collect measurement data pertaining to the operation of the light assembly  110  and correct the measurement data based on the temperature within the housing  120 , as is generally described herein. Although the node assembly  310  is shown disposed on a top portion of the housing  120 , the aspects of the disclosed embodiments are not so limited. In alternate embodiments, the node assembly  310  can be disposed on any suitable portion of the street light assembly  300 , including within the street light assembly  300 . 
     In one embodiment, the node assembly  310  includes a digital corrector device or circuit  320 . The digital corrector device  320  is generally configured to determine and provide the correction offset that is needed to adjust the measured electrical values related to the street light assembly  300 . This improves the accuracy of the measurements. In one embodiment, the digital corrector device  320  comprises or is part of a processor or controller, as will be generally described herein. 
     Referring also to  FIG. 4 , in one embodiment, the light portion  160  can also include or be electrically coupled to a driver or power supply for the LED module of the light assembly  110 . In one embodiment, the driver or power supply, also referred to as the LED driver, together with the other electrical components comprising the LED module, can be disposed on a printed circuit board  406  of the light portion  160  as is described with respect to  FIG. 4 . In one embodiment, as is described further herein and shown in  FIG. 4 , both the LED module and the LED driver can be disposed on the printed circuit board  406  in a manner as is generally understood. 
     Referring to  FIG. 4 , one embodiment of an exemplary electronics assembly  400  for the LED light assembly  110  and lighting module  160  of  FIG. 1  is illustrated. For the ease of the description herein, in the example of  FIG. 4 , the electronics assembly  400  is in the form of electrical and electronic components disposed on a printed circuit board  406 . In alternate embodiments, the electrical and electronic components for the LED light assembly  110  can be configured in any suitable manner, other than including on a printed circuit board. 
     In the example of  FIG. 4 , the assembly  400  includes at least one LED module  402 , a front lens portion  404 , also referred to as an optical cover part  404 , the printed circuit board  406  and an LED driver module  410 . In one embodiment, the LED light assembly  110  can include a heat sink  408  that is coupled to or part of the printed circuit board  406 . In alternate embodiments, the assembly  400  can include any other suitable electronic components, other than including those for an LED light assembly  110 . 
     The LED module  402  can comprise one or more LED chips or an array of LED chips. In the example of  FIG. 4 , there are six LED modules  402 , which may be referred to as an LED array. In alternate embodiments, any suitable number of LED modules  402  can be included, other than including six. For example, only one LED module  402  may be provided, the LED module  402  including one or more LED chips. The aspects of the disclosed embodiments are not limited by the number of LED modules  402  or chips that are incorporated in the LED assembly  400 . 
     The LED driver  410 , also referred to as a power supply, is generally configured to provide the electrical power and signals needed to operate the LED module(s)  402 , as was generally described with respect to  FIG. 1 . The aspects of the disclosed embodiments allow the LED driver  410  to be suitably positioned with the LED module(s)  402 , such as on the printed circuit board  406 . Alternatively, the LED driver  410  can be disposed within any suitable portion of the housing  120 . For example, the LED driver  410  can be disposed on a separate printed circuit board. 
     In the example of  FIG. 4 , the LED driver  410  can include a digital corrector device or module  320  incorporating aspects of the disclosed embodiments. The digital corrector device  320  is generally configured to correct for an offset in the measurement of current, voltage, active power, reactive power and energy due to the ambient temperature, and provide more accurate measurement results. In alternate embodiments, the digital corrector device  320  can be disposed in any suitable location with respect to the light assembly  110 . For example, referring to the example in  FIG. 3 , the digital corrector device or module  320  can be part of, or included in the node assembly  310 . In this manner, the light assembly  110  and the light module  160  can be manufactured independently of the digital corrector device  320 . 
     In one embodiment, as will be described below, the node assembly  310  is configured to be removably connected to the light assembly  110 , meaning that it can be connected and disconnected without interfering with the general operation of the light assembly  110 . In this case, the node assembly  310  would include a suitable connector, such as plug or twist type connector that allows the node assembly  310  to be connected and disconnected from the light assembly  110 . Such an embodiment where the digital corrector device  320  is part of the node assembly  310  provides more flexibility in manufacturing, 
     In one embodiment, one or more temperature sensors  450  are disposed on or in connection with the circuit assembly  400 . The temperature sensor(s)  450  is configured to measure or obtain the temperature, or data relating to the temperature of the operating environment of the light assembly  110 , and in particular, the light portion  160 , to which the measured parameters relate. 
     As will be described further below, the temperature sensor  450  can be a standalone device, or can also be part of another unit or electronics. The aspects of the disclosed embodiments are not intended to be limited by the manner in which the temperature within the housing  120  is determined or obtained. Generally, the temperature sensor  450  can be any suitable temperature sensor that can be used measure the temperature of the environment in which the light assembly  110  and light module  160  are operating. For example, in one embodiment, the temperature sensor  450  is a thermocouple device. The thermocouple device can be disposed on a suitable portion of the circuit board assembly  400 . 
     Although the aspects of the disclosed embodiments are described with respect to the temperature sensor(s)  450  being disposed on the circuit board assembly  400 , the aspects of the disclosed embodiments are not so limited. In alternate embodiments, the temperature sensor(s)  450  can be disposed within or on any part of the light assembly, such as the lighting assembly  100  shown in  FIG. 1 . For example, in one embodiment, referring to  FIG. 1 , one or more temperature sensors  450  are disposed on or within the housing  120  in a manner so as to measure the ambient temperature in and around the electrical and electronic components of the light assembly  110 . In this manner, the temperature sensor(s)  450  is generally configured to determine the temperature within the housing  120 , which is the environment in which the electrical and electronic components of light assembly  110 , and in particular the light module  160 , are operating. 
     In one embodiment, referring also to  FIG. 11 , the digital corrector device  320  comprises a processor  1002 , such as a microprocessor. When the digital corrector device  320  is disposed in the node assembly  310 , the digital corrector device  320  may be or have its own processor. When the digital corrector device  320  is part of the circuit board assembly  400  of  FIG. 4 , the digital corrector device  320  may be or have its own processor, or share a processor already included in the printed circuit board assembly  400 . For example, the processor  1002  can be part of the digital corrector  320  or a standalone device. 
     Although the aspects of the disclosed embodiments will describe the digital corrector  320  as being part of the LED driver module  410 , the aspects of the disclosed embodiments are not so limited. In alternate embodiments, the digital corrector  320  can be a separate electronic circuit, device or module, or be included in or part of another processing device, such as a microprocessor or a controller that comprises or includes the processor. In one embodiment, the temperature sensor(s)  450  generally described above can be included with, or part of the digital corrector device  320 . 
     In one embodiment, the digital corrector device  320  comprises a computer program product disposed on a non-transitory computer readable medium. For example, in this embodiment, the digital corrector  320  is comprised of machine-readable instructions, that when executed by the processor  1002  shown in  FIG. 11 , are configured to carry out the processes generally described herein. 
       FIG. 5  illustrates an exemplary process incorporating aspects of the disclosed embodiments. In this example, the performance of the street light assembly  100  is being monitored by measuring various electrical parameters. For example, in one embodiment, one or more of the street light assembly  100  and the node  320  can include certain electrical and electrical components, and in particular digital components, that are configured to measure and monitor the electrical consumption of the light assembly  110  in terms of current, voltage, power and energy. In alternate embodiments, any suitable parameters can be measured to monitor the electrical performance of the light assembly  110 . 
     In one embodiment, measurements of one or more electrical parameters of the street light are obtained  502 . The measurements can be obtained in any suitable manner. For example, in one embodiment, a measurement unit or circuit, such as a voltmeter or ammeter, can be used to measure the desired parameters of the street light assembly  100 . The measurement unit, also referred to as an electrical parameter meter, can be part of the node assembly  320  shown in  FIG. 3 , part of the electronics shown on the circuit board assembly  400  of  FIG. 4 , or a separate unit. 
     A temperature of the environment within which the street light electronics are disposed is obtained or detected  504 . The temperature can be obtained in any suitable manner, such as by using the temperature sensor  450 . Generally, when the electronics and electrical components are disposed within a housing, such as the housing  120  of  FIG. 1 , the temperature sensor  450  is configured to detect  504  the temperature within the housing  120 . 
     In one embodiment, it is determined  506  whether the detected temperature is substantially equal to a pre-determined ambient temperature. If the temperature of the environment in which the electronics of street light are operating is within an ambient or expected temperature range, it may not be necessary to apply a correction factor to the measurements. For example, the electronics of the street light assembly  110  may be configured to operate in accordance with certain standard values at a pre-determined temperature or temperature range. In this case, it will be understood that the measured parameters are generally accurate within certain temperature tolerances and ranges, and there may not be a need to apply any correction or offset. Alternatively, even when the street light is operating within a standard or controlled temperature environment, a correction factor can still be determined and applied to the measurement results in the manner as is generally described herein. 
     If the detected temperature is not at or within an ambient temperature range, a correction factor to be applied to the measurement results is determined  508 . In one embodiment, the correction factor or offset is obtained from a database of correction factors. Alternatively, a corrector function can be applied to the measure values as will be discussed below with respect to  FIG. 7 . The database can be established by testing the electronics at certain temperatures and then determining a correction factor for each temperature. These correction factors or values can be stored in a memory device and retrieved as needed. In alternate embodiments, the correction factors can be determined and stored in any suitable manner. 
     In one embodiment, the database of correction factors can be stored on a memory  1004  of the street light assembly  100 , with reference to  FIG. 11 . In alternate embodiments, the database of correction factors can be stored in any suitable facility. For example, the street light assembly  300  can include communication capabilities that allow it to request and download the correction factors when desired. 
     The determined correction factor is then applied  510  to the measurement result(s). In this manner, the results of the measurement of parameters such as voltage, current and power are more accurate. Thus, the power and energy consumption factors of a LED lamp operating in a non-ambient temperature environment are more accurately portrayed. 
       FIG. 6  illustrates an exemplary curve of energy measurement error. In this example, the temperature in degrees Celsius is indicated along the X axis, while the energy measurement error in terms of percentage is shown on the Y axis. The temperature compensation is a digital correction based the feedback from the current and voltage measurements. In the example of  FIG. 6 , at a temperature of 22 degrees Celsius, the energy measurement error is approximately 0.5 percent. In this example, 1.8 is the maximum error in terms of percentage. It is noted that the energy measurement error can rise relative to both an increase in temperature as well as a decrease in temperature. 
     The curve of the energy measurement error is a function of the temperature and moreover, it is approximatively a second degree polynomial. This second order function is deduced from an interpolation of the energy error curve. In one embodiment, the energy error is measured with an energy calibrator. The energy calibrator finds application in the street light assembly  100  as is shown in  FIG. 1  and can be part of the node assembly  310  and digital corrector device or circuit  320  shown in  FIG. 3 . The energy calibrator can also be disposed in a home energy or utility meter. 
       FIG. 7  illustrates an exemplary corrector function for the digital corrector device  320  incorporating aspects of the disclosed embodiments. In this example, the corrector function is a function of a temperature value that is measured as close as possible to the electronics of the lighting assembly  110 , and in particular the LED driver. In embodiments where the digital corrector device  320  is implemented in a device other than including a street light assembly, such as an electrical meter, the temperature value that is provided to the digital corrector device  320  is measured at a point as close as possible to the electronic components. 
     For example, a typical electric utility meter can be located in an outdoor environment. In such an environment, the utility meter is subject to the environment, and the temperature in the specific environment. Thus, electrical parameter measurements taken at the meter can be affected by temperature. It is noted that in this embodiment, the actual electrical components or devices that are operating and consuming power may not be subject to the unregulated temperature in which the meter itself is located. By disposing the digital corrector module  320  with an electric meter, more accurate electricity consumption measurements can be obtained. In this manner, the measurement values can be modified to provide more accurate measurements and adjust for the effect of temperature on the measured values. 
     In the example of  FIG. 7 , kT is the time, TC 1  and TC 2  are the gains of the corrector, and Meas(kT) is an electrical parameter or value measured at the time kT. The exemplary corrector function for digital corrector device  320  of the disclosed embodiments improves the voltage and current measurement, and provides improved accuracy of the energy measurement. In one embodiment, the accuracy of the digital corrector device  320  of the disclosed embodiments, using for example the corrector function illustrated in  FIG. 7 , can be between −0.5 and +0.5. These improvements in the accuracy of electrical parameter measurements can be realized using the digital corrector device  320  of the disclosed embodiments, even if the electrical and electronic hardware of the lighting assembly  110  or the node  310  changes slightly. In one embodiment, the corrector function shown in  FIG. 7  can be implemented in a processor of the digital corrector device  320 . Where the processor is embodied or implemented in the form of a chip, or other integrated circuit, the chip can be reprogrammed without the need to change hardware. 
       FIG. 8  illustrates one example of the node assembly  310  shown in  FIG. 3 . Referring also to  FIG. 3 , the node assembly  310  is configured to connect to the light assembly  110 . In the example of  FIG. 3 , node assembly  310  is plugged into the light assembly  110  in a manner that allows the node assembly  310  to directly couple to or connect with the electrical lines that provide electrical power to the street light assembly  100 . The node assembly  310 , and in particular the digital corrector device  320 , and detect and measure the electrical parameters of the light assembly  110 , such as those described herein. Where the device is a utility meter, the utility meter can be configured to allow the node assembly  310  to plug into the utility meter in a manner as is generally described herein. 
     As shown in the example of  FIG. 8 , the node assembly  310  includes a connector  802 . The connector  802  can comprise a power mains connector that connects or plugs into a suitable receptacle on the top portion of the light assembly  110 . The receptacle in the light assembly  110  is coupled or connected to at least the power mains of the light assembly  110 . 
     In one embodiment, the temperature sensor(s)  450  and the digital corrector module  320  can be included in, or part of the node assembly  310 . In this example, the sensor  450  and digital corrector device  320  might be disposed on a printed circuit board or such other suitable assembly inside the node assembly  310 . In an alternate embodiment, the node  310  can include a processor  1002  that includes or is configured to carry out the functionality and processes of the digital corrector device  320  and temperature sensor  450  as those function and processes are described herein. As an example, in one embodiment, the node assembly  310  can include an integrated circuit or chip, that is specially programmed with the functionality of the digital corrector module  320  as is described herein. 
     In one embodiment, the node assembly  310  and the digital corrector device  320  can be configured to communicate with a network, in a manner as is generally understood. The network can be wired or wireless. In one embodiment, the digital corrector device  320  is configured to communicate with a database to obtain the offset correction values as are described herein. In one embodiment, the database can be remotely located from the node assembly  310 , such as in a server. This can allow of the values in the database to be updated as needed. Alternatively, the offset correction values can be stored in a memory device that is accessible by the node assembly  310  and the digital corrector module  320 . The memory or storage device can be part of the digital corrector device  320 , or remotely located. 
       FIG. 9  illustrates one example of a wireless control system  900  for street and roadway lights incorporating aspects of the disclosed embodiments. In this example, the system  900  is configured for the remote operation and monitoring of one or more lighting fixture assemblies  910  through a Web-enabled management system. 
     In the example of  FIG. 9 , the node  310  is disposed at the top portion of the light fixture  910  and is configured to collect measurement data and send it to a wireless gateway  920 . The light fixture  910  is similar to the light fixture  300  described with respect to  FIG. 3 . The wireless gateway  920  is configured to communicate with the node assembly  310 , transferring specific street light usage and performance data. In one embodiment, the street light usage and performance data includes, but is not limited to measurement parameters for current, voltage, power and energy. These measured parameter values are transmitted or otherwise communicated to the digital corrector device  320 , as is otherwise described herein. 
     In one embodiment, the data can be delivered via a network  930 , such as a cellular or Ethernet backhaul, to a server facility. In this manner, the data can be made available to any one of a number of parties or entities. In the example of  FIG. 9 , the lighting data for each lighting fixture, including the measurement data described herein, can be made available via a Web-based interface  940  that can be hosted remotely, for example. In this manner, authorized users can view the performance of the lighting fixtures. 
       FIG. 10  illustrates another exemplary node assembly  910  incorporating aspects of the disclosed embodiments. In this example, the node assembly  910  is similar to the node assembly  310  described with respect to  FIG. 3 , and is configured to provide the same or similar functionality. In this example, the interior layout of the node assembly  910  is shown. In the example of  FIG. 10 , the node assembly  910  includes connector  902 , similar to connector  802  in  FIG. 8 . The node assembly  902  includes printed circuit boards  904 ,  906  that include electrical and electronic components disposed thereon. For example, the temperature sensor  450  and digital corrector device  320  can be included therein. In one embodiment, the electrical measurement device(s)  908  can be disposed within the node assembly  910 . The particular placement of the temperature sensor  450 , digital corrector device  320  and measurement device(s)  908  in the node  910  illustrated in  FIG. 10  is merely exemplary. In alternate embodiments, the temperature sensor  450 , digital corrector device  320  and measurement device(s)  908  can be located in any suitable position within the node  920 . 
       FIG. 11  illustrates a block diagram of an apparatus  1000  that can be used to practice aspects of the present disclosure. The apparatus  1000  is appropriate for implementing embodiments of the digital corrector device and temperature correction process described herein. Individual ones of the apparatus  1000  as described herein can be implemented in or in conjunction with, the node  310  described herein. 
     The apparatus  1000  generally includes a processor  1002 . The processor  1002  may be a single processing device or may comprise a plurality of processing devices including special purpose devices, such as for example digital signal processing (DSP) devices, microprocessors, or other specialized processing devices as well as one or more general purpose computer processors including parallel processors or multi-core processors. The processor  1002  is configured to perform embodiments of the processes described herein. 
     The processor  1002  is coupled to a memory  1004  which may be a combination of various types of volatile and/or non-volatile computer memory such as for example read only memory (ROM), random access memory (RAM), magnetic or optical disk, or other types of computer memory. The memory  1004  stores computer program instructions that may be accessed and executed by the processor  1002  to cause the processor  1002  to perform a variety of desirable computer implemented processes or methods as are described herein. The program instructions stored in memory  1004  may be organized as groups or sets of program instructions referred to by those skilled in the art with various terms such as programs, software components, software modules, units, etc., where each program may be of a recognized type such as an operating system, an application, a device driver, or other conventionally recognized type of software component. Also included in the memory  1004  are program data and data files which may be accessed, stored, and processed by the computer program instructions. 
     An RF Unit  1006  can be coupled or connected to the processor  1002 . The RF unit can also be coupled to antennas  1010  and is configured to transmit and receive RF signals based on digital data  1013  exchanged with the processor  1002 . In transmitter applications, the RF Unit  1006  is configured to receive digital information in the form of digital data  1013  from the processor  1002  and transmit it to one or more receivers such as described with respect to  FIG. 9  herein. 
     In an embodiment of an apparatus  1000  that includes a UI  1008 , the UI  1008  may include one or more user interface elements such as a touch screen, keypad, buttons, voice command processor, as well as other elements adapted for exchanging information with a user. The user interface  1008  can be in the form of an indicator to illustrate the operation of the node  310  or even to display certain measurement results as desired. 
     The aspects of the disclosed embodiments are directed to correcting for the effect temperature has on the measurement of electrical performance parameters of electronic devices, such as an LED street lamp. By providing a digital corrector device that can be removably coupled to the street lamp, the aspects of the disclosed embodiments can adjust or correct for variations in the results of the measurement of electrical parameters, where the temperature affects those results. The device of the disclosed embodiments improves the accuracy of any current, voltage, power and energy measured on a device, such as an LED street lamp. 
     By implementing the digital corrector device on a node, such as that described herein, the deployment does not require a material change to the LED street lamp. The LED lamp also does not need to be modified to protect the digital components from the temperature variations in order to obtain accurate results. The aspects of the disclosed embodiments also provide for more reliable monitoring of an electrical device such as a street lamp, particularly when it has been in the field a number of years. The aspects of the disclosed embodiments also provide for improved accuracy and reproducibility of the measurements, which can be compared to factory results for monitoring equipment performance. 
     Thus, while there have been shown, described and pointed out, fundamental novel features of the invention as applied to the exemplary embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of devices and methods illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. Moreover, it is expressly intended that all combinations of those elements and/or method steps, which perform substantially the same function in substantially the same way to achieve the same results, are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.