Claims:1. A method for storing, accessing and modifying correction parameters obtained during calibration of the electronic trip unit, the method comprising steps of:
obtaining the correction parameters and storing them in non-volatile memory of processor of the trip unit;
providing unique memory addresses to the correction parameters;
providing the unique memory address to a lock register; and
unlocking the lock register with a predefined value to access or modify correction parameters.

2. The method of claim 1, wherein the communication protocol for the method is a wired communication protocol.
3. The method of claim 2, wherein the wired communication protocol is selected from group comprising SPI, SCI, CAN, Modbus, USB, Profibus and Ethernet.
4. The method as claimed in claim 1, wherein the communication protocol for the method is a wireless communication protocol.
5. The method as claimed in claim 4, wherein the wireless communication protocol is selected from group comprising ZigBee and Bluetooth.
6. The method as claimed in claim 1, wherein the lock register is locked after accessing the correction parameters.
7. The method as claimed in claim 1, wherein the lock register gets auto-locked after predefined idle time. , Description:FIELD OF THE INVENTION
[0001] The present disclosure generally relates to low voltage power distribution systems. In particular it pertains to a method for modifying and storing correction parameters obtained during calibration of an electronic trip unit.

BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Electronic trip units typically consist of two stages: a power supply stage and a signal conditioning stage. Power supply stage uses current transformer output to generate voltage to pop flux shift device in case of trip and to power up the microcontroller. In the signal conditioning stage noise from the signal is filtered out and attenuation/amplification of signal is done for ADC sampling. Circuit breakers use Rogowski output for metering and protection purposes. There are many sources of error such as Rogowski output error, deviation of AC gain and DC gain (of signal conditioning circuit) from the ideal value. During the process of calibration, the actual value of these parameters are computed and saved in a non-volatile memory. When the calibration is done at breaker level, communication port is used to communicate correction factors to the trip unit so that it can be saved in the non-volatile memory. There is a need to access these parameters on site for debugging purpose. However, user should not be able to access these parameters and should be accessible only to site engineers who are aware of the processes involved to view and modify, if required.
[0004] Prior art references disclose systems and methods for calibration of ETUs. For example United States patent no. 20140278179 methods and systems for continuous calibration of circuit breaker Trip Units and Metering Devices that includes a processor and a memory device. The computer is configured to determine a plurality of calibration factors for the circuit breaker trip units based upon the circuit breaker current data and the main current data. The computer is additionally configured to transmit the calibration factors to the circuit breaker trip units.
[0005] United States patent no. 4550360 discloses an analog signal processor used within a static trip unit provided with an A/D converter, a digital processor and an electrically alterable non-volatile memory (EAROM) for providing trimming and calibration facility to the trip unit. The EAROM provides the ability to store parameters calculated by the user during the manufacturing process of the trip unit.
[0006] United States patent nos. 7859811 and 20100211196 relate to communication module plug-in device for an electronic trip unit including both wired and wireless conventional communication methodologies. United States patent no. 7129688 refers to calibration process using communication bus.
[0007] None of the prior art references disclose a method for access, modification and storage of correction parameters (that are stored in the non-volatile memory during the process of calibration) using conventional wired protocols and wireless protocols.
[0008] There is therefore a need in the art to provide a method by which correction parameters obtained in the process of calibration of electronic trip unit can be accessed, modified and stored at later stage. Need is also observed to restrict the access of these correction factors to only authorized persons.
[0009] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0010] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0011] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0012] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0013] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all markush groups used in the appended claims.

OBJECTS OF THE INVENTION
[0014] A general object of the present disclosure to provide a method for accessing, modifying and storing correction parameters obtained during calibration of the electronic trip unit.
[0015] An object of the present disclosure to provide a method for accessing, modifying and storing correction parameters using conventional wired and wireless communication protocols.
[0016] Another object of the present disclosure is to a method for accessing, modifying and storing correction parameters that can be applicable for processor-based metering and protection devices which use communication.
[0017] Yet another object of the present disclosure to restrict the access to the correction parameters to only authorized persons.

SUMMARY
[0018] Aspects of the present disclosure relate to a method for accessing, modifying and storing correction parameters obtained during calibration of the electronic trip unit. In an aspect the disclosed method for accessing, modifying and storing correction parameters uses conventional wired and wireless communication protocols.
[0019] In an aspect, the disclosed method for providing access, modification and storage of correction parameters obtained during calibration of the electronic trip unit can comprise steps of a) obtaining the correction parameters and storing them in non-volatile memory of processor; b) providing unique addresses in the memory map to the correction parameters obtained during calibration; c) providing unique memory map address to lock register; d) restricting the access to the correction parameters through the lock register; e) unlocking the lock register with known value to access or modify correction parameters; and f) Locking the lock register with known value or it gets automatically locked when time out occurs
[0020] In an aspect, the present disclosure provides for unique memory map addresses to the correction parameters that enables later accessing and reading-writing of the same. In another aspect of the invention, access to these correction parameters can be restricted to the authorized persons only by use of the lock register. Once unlocked, after the access, modification and storage of the correction parameters in the non-volatile memory, register can be locked again. In an alternate embodiment, register can get auto locked after predefined time period for which registers for correction parameters are not accessed.
[0021] In a preferred embodiment of the present disclosure, different communication protocols that can be used in the present disclosure to access the correction parameters can be wired protocols selected from the group comprising of SPI, SCI, CAN, Modbus, USB, Profibus and Ethernet.
[0022] In another preferred embodiment of the present disclosure, different communication protocols that can be used in the present disclosure to access the correction parameters can be wireless protocols selected from the group comprising of ZigBee and Bluetooth.
[0023] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components

BRIEF DESCRIPTION OF DRAWINGS
[0024] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0025] FIG. 1 illustrates an exemplary block diagram of an electronic trip unit.
[0026] FIG. 2 illustrates an exemplary method flow diagram indicating working methodology for restricting the access of the correction factors to authorized persons only in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0027] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0028] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0029] Various terms as used herein. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0030] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0031] Aspects of the present disclosure relate to a method for accessing, modifying and storing correction parameters obtained during calibration of the electronic trip unit. In an aspect the disclosed method for accessing, modifying and storing correction parameters uses conventional wired and wireless communication protocols.
[0032] In an aspect, the disclosed method for providing access, modification and storage of correction parameters obtained during calibration of the electronic trip unit can comprise steps of a) obtaining the correction parameters and storing them in non-volatile memory of processor; b) providing unique memory addresses in the memory map to the correction parameters obtained during calibration; c) providing unique memory map address to lock register; d) restricting the access to the correction parameters through the lock register; and e) unlocking the lock register with known value to access or modify correction parameters; and f) Locking the lock register with known value or it gets automatically locked when time out occurs
[0033] In an aspect, the present disclosure provides for unique memory addresses to the correction parameters that enables later accessing and reading-writing of the same. In another aspect of the invention, access to these correction parameters can be restricted to the authorized persons only by use of the lock register. Once unlocked, after the access, modification and storage of the correction parameters in the non-volatile memory, register can be locked again. In an alternate embodiment, register can get auto locked after predefined time period for which registers for correction parameters are not accessed.
[0034] In a preferred embodiment of the present disclosure, different communication protocols that can be used in the present disclosure to access the correction parameters can be wired protocols selected from the group comprising of SPI, SCI, CAN, Modbus, USB, Profibus and Ethernet.
[0035] In another preferred embodiment of the present disclosure, different communication protocols that can be used in the present disclosure to access the correction parameters can be wireless protocols selected from the group comprising of ZigBee and Bluetooth.
[0036] Figure 1 illustrates a typical block diagram 100 indicating working of an electronic trip unit. When a current is passed through the circuit breaker, the current output is available at secondary of current transformer 120 and voltage output is available at output of Rogowski coil 110. The current transformer output is given to power supply module 140 and the Rogowski output is given to signal conditioning module 130. The signal conditioning module has certain AC gain and DC gain. The power supply is also made available to flux shift device (FSD) 160 through trip circuit 150. The power supply signal is passed through regulator 170 and used for powering the microcontroller 180.
[0037] Figure 2 illustrates an exemplary flow diagram 200 indicating working of the disclosed method for accessing and modifying the correction factors. In an embodiment, a separate memory map can be made available for correction parameters as shown at step 202. At step 204, an additional register (lock register) can be provided. In an aspect the lock register can be unlocked with predefined value. When an attempt is made to access, modify and store the correction parameters a check can be made at step 206 if the lock register is locked or timed out. If YES, at step 210 an output indicating an invalid address can be provided. Alternatively if the result of the check at step 206 is NO the correction parameter can be accessed, modified and stored in the non-volatile memory and locked again. In an alternative embodiment, the register can get automatically locked on time out for idle.
[0038] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
[0039] The present disclosure provides a method for accessing, modifying and storing correction parameters obtained during calibration of the electronic trip unit.
[0040] The present disclosure provides a method for accessing, modifying and storing correction parameters using conventional wired and wireless communication protocols.
[0041] The present disclosure provides a method for accessing, modifying and storing correction parameters that can be applicable for processor-based metering and protection devices which use communication.
[0042] The present disclosure provides restricts the access to the correction parameters to only authorized persons.