Claims:1. An electronic overload relay having an auto-reset functionality, said relay comprising:
a current transformer (CT) configured to supply current when no fault is sensed;
a controller; and
a power bank, wherein when the controller senses presence of a fault, the power bank is charged for a programmable time delay so as to provide power to the controller.

2. The electronic overload relay of claim 1, a trip signal is issued, wherein after the programmable time delay the relay is reset.

3. The electronic overload relay of claim 1, wherein the reset delay is programmed by a user/operator.

4. The electronic overload relay of claim 1, wherein the controller is run in STOP mode after it senses the presence of the fault.

5. A method to reset an electronic overload relay, said method comprising the steps of:
receiving normal current supply from a current transformer;
sensing, by means of a controller, presence of a fault;
determining if the relay is configured for auto-reset;
based on determination that the relay is configured for auto-reset, charging a power bank to provide power to the controller;
issuing a trip signal after that with the programmed time delay automatically reset the relay.

6. The method of claim 5, wherein if it is determined that the relay is not configured for auto-reset, manual reset operation is executed.
, Description:TECHNICAL FIELD
[0001] The present disclosure relates generally to overload relays, and more particularly, to a Programmable RESET Operation for Electronic Overload Relay (EOLR).

BACKGROUND
[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] An electronic overload relay detects a load current of a motor by a current detecting device (such as a CT), and if a detected load current exceeds a set value, the electronic overload relay flows operating current to a polarized electromagnet from a current detection circuit, and performs a trip operation for opening and closing a control circuit contact.
[0004] By the trip operation, a normally-open contact (contact a) is closed to turn on an indicator lamp, and a normally-closed contact (contact b) is opened to release excitation of an electromagnet of an electromagnetic contactor of a load circuit of a motor, thereby blocking the load circuit to prevent an accident such as burnout of the motor. After the trip operation, to restart the motor, it is necessary to perform a reset operation for returning the overload relay to a state before the trip operation (a state where the normally-open contact is opened and the normally-closed contact is closed).
[0005] The reset operation includes a manual reset operation that is performed by operating a reset bar, and an automatic reset operation that is performed by operating a polarized electromagnet using operating current output from a current detection circuit after a predetermined time is elapsed after the trip operation. This reset operation has to be performed after the cause of the overload of the load circuit of the motor is eliminated.
[0006] In electronic overload relays, architecture for tripping and resetting the relay is altogether different from thermal relays.In existing thermaloverload relays, resetting is done by repositioning of bi-metal, which is not in user’s control as it depends on cooling of the bi-metal.
[0007] Also in electronic overload relays, the auto-reset time is fixed which is not adjustable by the user. There is therefore a need for an electronic overload relay with an improved reset operation.
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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
[0013] It is an object of the present disclosure to provide an electronic overload relay with an improved reset operation.
[0014] It is an object of the present disclosure to provide a contactor mounted electronic overload relay programmable auto-reset operation.

SUMMARY
[0015] The present disclosure relates generally to overload relays, and more particularly, to a Programmable RESET Operation for Electronic Overload Relay (EOLR). The invention further relates to a contactor mounted electronic overload relay programmable auto- reset operation.
[0016] In an aspect, the present disclosure enables efficiently resetting the electronic overload relay with the help of an internal rechargeable power bank, wherein the complete architecture is designed in order to provide a programmable delay for resetting the relay. Furthermore, the proposed disclosure provides a feedback means from an operator to program the delay setting for resetting the relay.
[0017] In an aspect, the present disclosure provides an accurate and programmable time delay for auto-resetting the electronic overload relay.
[0018] In an aspect, the present disclosure relates to an electronic overload relay having an auto-reset functionality, wherein the relay can include or be operatively coupled with a current transformer (CT) configured to supply current when no fault is sensed; a controller; and a power bank, wherein when the controller senses the presence of a fault, the power bank is charged to provide power to the electronic board.
[0019] In an aspect, a trip signal is issued according to the delay curve selected by user, and the relay will get reset after a preset time delay programmed by the user through rotary switch. In another aspect, the reset delay can be programmed by a user/operator. In yet another aspect, the controller can be run in STOP mode after it senses the presence of a fault.
[0020] The present disclosure further relates to a method to reset an electronic overload relay, said method comprising the steps of receiving normal current supply from a current transformer; sensing, by means of a controller, presence of a fault; determining if the relay is configured for auto-reset; based on determination that the relay is configured for auto-reset, charging a power bank to provide power to the controller; and issuing a trip signal so as to automatically reset the relay after the preset time delay programmed by the user through rotary switch.
[0021] In an aspect, if it is determined that the relay is not configured for auto-reset, manual reset operation can be executed.
[0022] In an exemplary embodiment, in the proposed design, a programmable auto-reset can be configured by using a feature of STOP mode of a controller, which allows extremely low consumption of controller due to which power bank draining reduced. In an aspect, STOP mode achieves lowest power consumption by enabling only the timer with all the other CPU function disabled.
[0023] In electronic relays, there are two ways for tripping a circuit, one is to use electromechanical relay mechanism and another one is to use electromagnet flux device. As we are using extrusive feature of auto-reset, we have used dual coil electromechanical relay which operates in two contrarily directions by applying power supply to each respective coil. There are two ways of powering on the Electronic board, one is through auxiliary power and other is self-powered. Our design bank-on self-powered in which current transformer (CT) is used to power on the electronic board.
[0024] In the proposed design, the controller is being used in such a power efficient mode that it is not consuming power continuously, to reduce the burden load on CT. Once the fault occurs controller sense the fault, and with the preset input of keeping the auto reset ON with the preset delay programmed through rotary switch ,controller controls the charging of the power bank efficiently which provide power to the circuit immediately after the power failure caused by the fault. After the power failure, the controller efficiently employs the STOP mode so as to reduce the power consumption of the electronic board and after the preset time delay set through rotary switch by the user the electronics system will get auto –reset to power healthy state.
[0025] The proposed feature allows an operator to program cooling time of the load. The proposed system configuration can allow an operator to use the same range of relay for a variety of loads depending on the cooling time required. Furthermore, the proposed disclosure provides a hardware circuit and an efficient software algorithm for power efficient usage of the system. In addition to that this invention opens the possibility of indicating the fault history through LED for the preset reset time, which will consume power from the same power bank as the electronic board consumption reduced to extremely low level
[0026] 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 THE DRAWINGS
[0027] 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.
[0028] FIG. 1 illustrates power bank charging through current transformer in power supply section in accordance with an embodiment of the present disclosure.
[0029] FIG. 2 illustrates an exemplary flow diagram of the working of the auto-reset operation for an electronic overload relay in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0030] 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.
[0031] 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.
[0032] 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.
[0033] 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.
[0034] Various terms as used herein are shown below. 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.
[0035] The present disclosure relates to an electronic overload relay having an auto-reset functionality, wherein the relay can include or be operatively coupled with a current transformer (CT) that is configured to supply current when no fault is sensed; a controller; and a power bank, wherein when the controller senses presence of a fault, the power bank is charged to provide power to the controller. The relay is then automatically reset after the programmable time delay set through rotary switch, wherein the delay can be configured/programmed by a user/operator.
[0036] The present disclosure relates generally to overload relays, and more particularly, to a Programmable RESET Operation for Electronic Overload Relay (EOLR). The invention further relates to a contactor mounted electronic overload relay programmable auto- reset operation.
[0037] In an aspect, the present disclosure enables efficiently resetting the electronic overload relay with the help of an internal rechargeable power bank, wherein the complete architecture is designed in order to provide a programmable delay for resetting the relay. Furthermore, the proposed disclosure provides a feedback means from an operator to program the delay setting for resetting the relay.
[0038] In an aspect, the present disclosure provides an accurate and programmable time delay for auto-resetting the electronic overload relay.
[0039] In an aspect, the present disclosure relates to an electronic overload relay having an auto-reset functionality, wherein the relay can include or be operatively coupled with a current transformer (CT) configured to supply current when no fault is sensed; a controller; and a power bank, wherein when the controller senses the presence of a fault, the power bank is charged to provide power to the controller. In an aspect, a trip signal is issued, and the relay is automatically reset after the preset time delay set through rotary switch. In another aspect, the reset delay can be programmed by a user/operator. In yet another aspect, the controller can be run in STOP mode after it senses presence of the fault.
[0040] The present disclosure further relates to a method to reset an electronic overload relay, said method comprising the steps of receiving normal current supply from a current transformer; sensing, by means of a controller, presence of a fault; determining if the relay is configured for auto-reset; based on determination that the relay is configured for auto-reset, charging a power bank to provide power to the controller in auto- reset mode; and issuing a trip signal.
[0041] In an aspect, if it is determined that the relay is not configured for auto-reset, manual reset operation can be executed.
[0042] In an exemplary embodiment, in the proposed design, a programmable auto-reset can be configured by using a feature of STOP mode of a controller, which allows low consumption of controller due to which power bank draining reduced. In an aspect, STOP mode achieves lowest power consumption by disabling more CPU functions.
[0043] In electronic relays, there are two ways for tripping a circuit, one is to use electromechanical relay mechanism and another one is to use electromagnet flux device. As we are using extrusive feature of auto-reset, we have used dual coil electromechanical relay which operates in two contrarily directions by applying power supply to each respective coil. There are two ways of powering on the Electronic board, one is through auxiliary power(external) and other is self-powered. Our design bank-on self-powered in which current transformer (CT) is used to power on the electronic board.
[0044] In the proposed design, the controller is being used in such a power efficient mode that it is not consuming power continuously, to reduce the burden load on CT. Once the fault occurs controller sense the fault, and with the preset input of keeping the auto reset ON with the preset delay programmed through rotary switch ,controller controls the charging of the power bank efficiently which provide power to the circuit immediately after the power failure caused by the fault. After the power failure, the controller efficiently employs the STOP mode so as to reduce the power consumption of the electronic board and after the preset time delay set through rotary switch by the user the electronics system will get auto –reset to power healthy state.
[0045] The proposed feature allows an operator to program cooling time of the load. The proposed system configuration can allow an operator to use the same range of relay for a variety of loads depending on the cooling time required. Furthermore, the proposed disclosure provides a hardware circuit and an efficient software algorithm for power efficient usage of the system. Besides, this invention opens the possibility of indicating the fault history through LED for the preset reset time, which will consume power from the same power bank as the electronic board consumption reduced to extremely low level
[0046] FIG. 1 illustrates power bank charging through current transformer in power supply section in accordance with an embodiment of the present disclosure. As shown, the proposed diagram 100 shows a power bank section that can be configured to charge a controller (in STOP mode)for a programmable time delay after a fault is sensed by the controller, upon completion of which delay, a reset signal is triggered and the relay is triggered.
[0047] FIG. 2 illustrates an exemplary flow diagram 200 of the working of the auto-reset operation for an electronic overload relay in accordance with an embodiment of the present disclosure. At step 202, normal current is supplied by a current transformer (CT), wherein at step 204, voltage is regulated by means of a low-dropout regulator. At step 206, a controller is configured to check the presence of fault, wherein if the fault is detected, it is determined, at step 208 if auto-reset functionality/feature is activated. In case the auto-reset functionality/feature is activated, at step 210, a power bank configured internal to the relay is charged. At step 212, time delay set by the user is read, upon completion of which, at step 214, a trip command/signal is issued, and, at step 216, the charged power bank is used to run the controller. At step 218, based on the issued trip command/signal, the relay is automatically reset and the method goes back to step 202.
[0048] On the other hand, if at step 208, it is determined that the auto-reset functionality/feature is not activated, at step 220, the trip command is issued to manually reset the relay, and the method goes back to step 202.
[0049] 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
[0050] The present disclosure provides an electronic overload relay with an improved reset operation.
[0051] The present disclosure provides a contactor mounted electronic overload relay programmable auto-reset operation.