Claims:
1. A residual current circuit breaker with overcurrent protection (RCBO) comprising an integrated unit having a solenoid coil and magnetic coil.
2. The RCBO of claim 1, wherein the RCBO comprises only one solenoid coil that forms part of the integrated circuit.
3. The RCBO of claim 1, wherein the integrated unit is electrically coupled with PCB.
4. The RCBO of claim 3, wherein a Core Balance Current Transformer (CBCT) is mounted on the PCB.
5. The RCBO of claim 1, wherein the solenoid coil is Residual Current Device (RCD) solenoid coil.
6. The RCBO of claim 1, wherein the magnetic coil is Miniature Circuit Breaker (MCB) magnetic coil.
7. The RCBO of claim 1, wherein the RCBO eliminates Earth leakage side solenoid bobbin, tripping mechanism associated therewith and adapted to provide the solenoid coil associated with the Residual Current Device (RCD) at magnetic section of a Miniature Circuit Breaker (MCB) and the magnetic coil associate with the MCB coil is provided on said the solenoid coil.
8. The RCBO of claim 1, wherein the magnetic coil is placed on the solenoid coil.
9. The RCBO of claim 1, wherein the integrated unit is operatively coupled with a switching mechanism.
10. The RCBO of claim 1, wherein the RCBO comprises a moving contact and a fixed contact, both of which are operatively coupled with the integrated unit.
, Description:TECHNICAL FIELD
[0001] The present invention relates to circuit breakers and, more particularly, relates to a compact residual current circuit breaker with overcurrent protection (RCBO) with a single tripping mechanism for overcurrent and earth leakage current protection.

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] Conventionally known, residual-current device (RCD) or residual-current circuit breaker (RCCB) is a device that instantly breaks an electric circuit to prevent serious harm from an ongoing electric shock. Injury may still occur in some cases, for example if a human falls after receiving a shock. Miniature circuit breaker (MCB), an electrical circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current, typically resulting from an overload or short circuit. An advanced technology, a Residual current breaker with over-current protection (RCBO) combines the functions of an RCD and an MCB in one package. Generally, Residual-current and overcurrent protection may be combined in one device for installation into the service panel, and these devices are known as a GFCI (ground fault circuit interrupter) breaker in the USA and Canada and referred to as RCBO in Europe.
[0004] RCBOs are commonly used in applications where there is the need to combine protection against overcurrent (overload and short-circuit) and protection against earth leakage currents. RCBOs help in sensing this kind of faults and trip the circuit ensuring complete protection of the people and connected equipment’s (loads). A conventional residual current circuit breaker with overcurrent protection ("RCBO") includes single housing configured to provide a miniature circuit breaker (MCB) portion and a residual current (for example, a ground fault) device (RCD) portion for providing combined protection from the risk of electrocution and protection against the risk of an electrical fire and overcurrent protection of equipment and cables. A typical conventional 1MOD RCBO is of a size of approximately 125 mm in height, 18 mm in width and 70 mm deep. Since RCBO combines the functions of an RCD and an MCB, the conventional RCBO includes various common parts/components as included in the RCD and the MCB.
[0005] FIG. 1 illustrates a cut away view of conventional RCBO with various components and their arrangement there within, as available in the prior-art. As shown in FIG. 1, the MCB 102 portion can include the MCB 102 components of the RCBO, and the RCD 104 portion can include the RCD components of the RCBO. The MCB components can include a fixed contact 106, a moving contact 108, an MCB magnetic winding (coil) 110, and a switching mechanism (mechanical linkage) 112. Further, there can be mainly one bi-metallic strip, one trip coil and one hand operated on-off lever. The RCD components can include a RCD solenoid winding (coil) 114 over the solenoid bobbin 124, wires connected to PCB 116, a neutral primary 118, a Current Balanced Core Transformer (CBCT) mounted on PCB 120, a phase primary 122. The neutral primary 118 and the phase primary 122 wires are connected through RCD. The conventional RCBO 100 also include a trip pin (connecting link) 126 which connects the RCD solenoid coil plunger128 and the switching mechanism (mechanical linkage) 112.
[0006] In normal condition, the MCB 102 works as switch. In exemplary working, if MCB 102 is overloaded the bi-metallic strip becomes over heated and deformed. This deformation of bi-metallic strip causes displacement of latch point. The moving contact 108 of the MCB is so arranged by means of spring pressure, with this latch point, that a little displacement of latch causes, release of spring and makes the moving contact 108 to move for opening the MCB. The current coil or trip coil 126 is placed such a manner that during short circuit fault the magneto motive force (MMF) of that coil causes its plunger to hit the same latch point and make the latch to be displaced. Hence the MCB 102 will open in same manner. When operating lever of the MCB is operated by hand, that means when user makes the MCB at off position manually, the same latch point is displaced as a result moving contact 108 separated from fixed contact 106 in same manner. When the moving contact 108 separated from fixed contact 106, there may be a high chance of arc. This arc then goes up through the arc runner and enters into arc splitters and is finally quenched. When user switch on an MCB 102, user actually reset the displaced operating latch to its previous on position and make the MCB 102 ready for another switch off or trip operation.
[0007] In exemplary working of the RCD, the amount of current flows through the phase primary 122. Current difference between phase primary 122 and neutral primary 118 detect by RCD 104 through CBCT 120 in residual current device having a trip mechanism for isolating an electric supply to an electrical installation upon detection of a predetermined current imbalance between the line and neutral conductors of said electric supply. Further, the RCD solenoid winding (coil) 114 contains a compressed spring and plunger 128, which can be released by a relatively small amount of energy. This can produce enough force to trip the main mechanism which itself stores energy in springs when the Trip pin 126 is pushed to open the contacts.
[0008] In spite of the fact that RCBO combines the functions of an RCD and an MCB to provide efficient current protections for the equipment’s connected thereto, however there exist many technical problems in the conventional RCBO and/or the arrangement of the components associated with the conventional RCBO. One such major technical problems is that when any earth leakage occurs in the equipment, there may be part of phase current passes to the earth, through the leakage path instead of returning via neutral wire. Hence the magnitude of the neutral current passing through RCBO is not equal to phase current passing through it. When this current difference crosses a predetermined value, generated voltage in CBCT 120 secondary winding acts as gate pulse to TRIAC and TRIAC become conductive and passes rated voltage to RCD solenoid coli 114 which operates the switching mechanism disconnects the power supply to the instrument under protection. It is mandate that to operate the electronic components PCB is to be always connected to supply voltage.
[0009] Further technical problem is an issue of de-latching in the RCD. Once the RCD is tripped in sensitivity (say when any earth leakage occurs), the RCD remains in de-latching state, until manually reset by an operator/administrator, and the cause of such de-latching is non-resetting of trip pin. Further, the conventional RCBOs require two solenoids are getting used i.e. one for tripping in case of Earth leakage and second one for tripping in case of short circuit, as there are two solenoids hence numbers of components like magnetic core, hammer, trip pin, resetting spring are increased and finally assembly time /cost of product increased and whole design is complicated. Thus, due to additional components the complexity in the arrangement and re-arrangement of the various components in the RCBO increases and needs timely maintenance and expertise for rectifying any error in such RCBO.
[0010] Also, in the RCBO’s available in the prior art, although it has been realized that the RCD device protects from residual current is cooperated with the tripping mechanism, it is necessary to provide a large tripping force, provided by the device, protecting from residual current, and the design margin is small. Thereby, in the events that an earth leakage fault occurs, the mechanism is contaminated and the tripper could not be tripped or tripped incorrectly, and the reliability is reduced.
[0011] Furthermore, the RCDs normally are electrical wiring devices that sever a circuit if an electric current is not balanced between an energized conductor and a neutral conduction path. Such a current imbalance may be caused by current leakage (e.g., earth leakage) through the body of a person who is grounded and accidentally touching an energized portion of a circuit with RCD protection. Thus, the RCDs provide earth leakage current protection, absent overcurrent protection. Thus, conventional RCDs are physically separate from overcurrent protection devices (e.g., circuit breakers/MCBs), and often require substantially additional physical space either through being connected serially to a device, or within the device, intended to be protected, or alongside the overcurrent protection devices.
[0012] While there is simply nothing wrong in the existing RCBOs that are readily available in the market today, however, with the growth and development of technology, and in view of the above and other technical problems available in the existing RCBOs, there still exists a need to provide a new, improved, and technically advanced RCBOs that provides an alternate way to eliminate the de-latching issue and makes the RCD assembly / tripping mechanism simplified (less complex). Further, there also exists a need to provide compact RCBOs with single module housing to accommodate both RCD portions and MCB portions and to provide a single tripping mechanism for earth leakage protection as well as overcurrent protection.
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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 groups used in the appended claims.

OBJECTS OF THE INVENTION
[0017] An object of the present disclosure is to provide a residual current circuit breaker with overcurrent protection (RCBO) with single tripping mechanism.
[0018] Another object of the present disclosure is to provide a voltage dependent RCBO with single tripping mechanism.
[0019] Another object of the present disclosure is to provide an RCBO that provides an alternate way to eliminate the de-latching and make RCD assembly / tripping mechanism simplified.
[0020] Another object of the present disclosure is to provide single module housing to accommodate both residual current detection (RCD) portions and miniature circuit breaker (MCB) portions with single tripping mechanism for earth leakage protection and overcurrent protection.
[0021] Another object of the present disclosure is to utilize one MCB coil wind on RCD solenoid coil and one tripling mechanism in RCBO for effective and efficient earth leakage protection and overcurrent protection.
[0022] It is another object of the present disclosure is to provide protection against leakage fault by shifting RCD solenoid winding at MCB magnetic section.

SUMMARY
[0023] Aspects of the present disclosure relate to a compact residual current circuit breaker with overcurrent protection (RCBO) with a single tripping mechanism for overcurrent and earth leakage current protection. In an embodiment, the present disclosure provides a voltage dependent RCBO with single tripping mechanism. Such RCBO provides an alternate way to eliminate the de latching and make RCD assembly / tripping mechanism simplified.
[0024] In order to the solve the technical problems as recited above, the present disclosure provides a new, improved, and technically advanced RCBOs that provides an alternate way to eliminate the de-latching issue and makes the RCD assembly / tripping mechanism simplified (less complex). Further, said RCBOs is compact in nature and provides a single module housing to accommodate both RCD portions and MCB portions and to provide a single tripping mechanism for earth leakage protection as well as overcurrent protection.
[0025] An aspect of the present disclosure relates to a residual current circuit breaker with overcurrent protection (RCBO) comprising an integrated unit having a solenoid coil and magnetic coil.
[0026] In an aspect, the integrated unit is electrically coupled with PCB. In an aspect, Current Balanced Current Transformer (CBCT) is mounted on the PCB. In an aspect, the integrated unit is operatively coupled with a switching mechanism.
[0027] In an aspect, the solenoid coil is Residual Current Device (RCD) solenoid coil. In an aspect, the magnetic coil is Miniature Circuit Breaker (MCB) magnetic coil. In an aspect, the magnetic coil is placed on the solenoid coil.
[0028] In an aspect, the RCBO eliminates Earth leakage side solenoid bobbin, tripping mechanism associated therewith and adapted to provide the solenoid coil associated with the Residual Current Device (RCD) at magnetic section of a Miniature Circuit Breaker (MCB) and the magnetic coil associate with the MCB coil is provided on said the solenoid coil.
[0029] In an aspect, the RCBO comprises a moving contact and a fixed contact, both of which are operatively coupled with the integrated unit.
[0030] The RCBO of the present disclosure is technically and logically different form the existing RCBOs in that, the RCBO of the present disclosure is compact in nature and the compactness is achieved by shifting/re-locating the RCD solenoid winding coil at MCB magnetic section and the MCB coil wind is moved on RCD solenoid winding coil. Further, the conventional RCBOs require two solenoids are getting used i.e. one for tripping in case of Earth leakage and second one for tripping in case of short circuit, as there are two solenoids hence numbers of components like magnetic core, hammer, trip pin, resetting spring are increased and finally assembly time /cost of product increased and whole design is complicated. To overcome all these issues the present disclosure eliminates earth leakage side solenoid bobbin and related tripping mechanism and shifts/re-locates/re-arranges the RCD solenoid winding at MCB magnetic section and the MCB coil is provided on RCD solenoid winding, due to there will be one tripping mechanism and one solenoid coil.
[0031] It would be appreciated that although aspects of the present disclosure have been explained with respect to RCBO device with overcurrent and earth leakage current protection in circuit protection technology, the present disclosure is not limited to the same in any manner whatsoever and any other form of circuit protection technology is completely covered within the scope of the present disclosure.
[0032] Other features of embodiments of the present disclosure will be apparent from accompanying drawings and from detailed description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS
[0033] 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.
[0034] In the figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label with a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
[0035] FIG. 1 illustrates a cut away view of conventional RCBO with various components and their arrangement there within and their working, as available in the prior-art.
[0036] FIG. 2 illustrates a cut away view proposed RCBO along with various components, their arrangement there within and their working, in accordance with an exemplary embodiment of the proposed disclosure.
[0037] FIGs. 3A-3K illustrates the components that are removed/rearranged/restructured form the proposed RCBO and the components that are newly manufactured and used in proposed RCBO, in accordance with an exemplary embodiment of the proposed disclosure.
[0038] FIG. 4 illustrates placement of a RCD solenoid coil and a MCB coil in the proposed RCBO, in accordance with an exemplary embodiment of the proposed disclosure.
[0039] FIG. 5 illustrates exemplary operating circuit for conventional RCBO as available in the prior-art.
[0040] FIG. 6 illustrates exemplary modified operating circuit for proposed RCBO, in accordance with an exemplary embodiment of the proposed disclosure.

DETAILED DESCRIPTION
[0041] Embodiments of the present disclosure include various steps, which will be described below. The steps may be performed by hardware components or may be embodied in machine-executable instructions, which may be used to cause a general-purpose or special-purpose processor programmed with the instructions to perform the steps. Alternatively, steps may be performed by a combination of hardware, software, and firmware or by human operators.
[0042] Embodiments of the present disclosure may be provided as a computer program product, which may include a machine-readable storage medium tangibly embodying thereon instructions, which may be used to program a computer (or other electronic devices) to perform a process. The machine-readable medium may include, but is not limited to, fixed (hard) drives, magnetic tape, floppy diskettes, optical disks, compact disc read-only memories (CD-ROMs), and magneto-optical disks, semiconductor memories, such as ROMs, PROMs, random access memories (RAMs), programmable read-only memories (PROMs), erasable PROMs (EPROMs), electrically erasable PROMs (EEPROMs), flash memory, magnetic or optical cards, or other type of media/machine-readable medium suitable for storing electronic instructions (e.g., computer programming code, such as software or firmware).
[0043] Various methods described herein may be practiced by combining one or more machine-readable storage media containing the code according to the present disclosure with appropriate standard computer hardware to execute the code contained therein. An apparatus for practicing various embodiments of the present disclosure may involve one or more computers (or one or more processors within a single computer) and storage systems containing or having network access to computer program(s) coded in accordance with various methods described herein, and the method steps of the disclosure could be accomplished by modules, routines, subroutines, or subparts of a computer program product.
[0044] If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[0045] Although, the present disclosure has been described for compact residual current circuit breaker with overcurrent protection (RCBO) with overcurrent and earth leakage current protection. It should be appreciated that the same has been done merely to illustrate the disclosure in an exemplary manner and any other purpose or function for which they explained structure or configuration can be used is covered within the scope of the present disclosure.
[0046] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be through and complete and will fully convey the scope of the disclosure to those of ordinary skill in the art. Moreover, all statements herein reciting embodiments of the disclosure, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure).
[0047] Thus, for example, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and the like represent conceptual views or processes illustrating systems and methods embodying this disclosure. The functions of the various elements shown in the figures may be provided through the use of dedicated hardware as well as hardware capable of executing associated software. Similarly, any electronic code generator shown in the figures are conceptual only. Their function may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the entity implementing this disclosure. Those of ordinary skill in the art further understand that the exemplary hardware, software, processes, methods, and/or operating systems described herein are for illustrative purposes and, thus, are not intended to be limited to any particular named.
[0048] 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.
[0049] Aspects of the present disclosure relate to a compact residual current circuit breaker with overcurrent protection (RCBO) with a single tripping mechanism for overcurrent and earth leakage current protection. In an embodiment, the present disclosure provides a voltage dependent RCBO with single tripping mechanism. Such RCBO provides an alternate way to eliminate the de latching and make RCD assembly / tripping mechanism simplified.
[0050] In order to the solve the technical problems as recited above, the present disclosure provides a new, improved, and technically advanced RCBOs that provides an alternate way to eliminate the de-latching issue and makes the RCD assembly / tripping mechanism simplified (less complex). Further, said RCBOs is compact in nature and provides a single module housing to accommodate both RCD portions and MCB portions and to provide a single tripping mechanism for earth leakage protection as well as overcurrent protection.
[0051] An aspect of the present disclosure relates to a residual current circuit breaker with overcurrent protection (RCBO) comprising an integrated unit having a solenoid coil (also referred to as solenoid winding) and magnetic coil (also referred to as magnetic winding).
[0052] In an aspect, the integrated unit is electrically coupled with PCB. In an aspect, a circuit breaker coil tester (CBCT) is mounted on the PCB. In an aspect, the integrated unit is operatively coupled with a switching mechanism.
[0053] In an aspect, the solenoid coil is Residual Current Device (RCD) solenoid coil. In an aspect, the magnetic coil is Miniature Circuit Breaker (MCB) magnetic coil. In an aspect, the magnetic coil is placed on the solenoid coil.
[0054] In an aspect, the RCBO eliminates Earth leakage side solenoid bobbin, tripping mechanism associated therewith and adapted to provide the solenoid coil associated with the Residual Current Device (RCD) at magnetic section of a Miniature Circuit Breaker (MCB) and the magnetic coil associate with the MCB coil is provided on said the solenoid coil.
[0055] In an aspect, the RCBO comprises a moving contact and a fixed contact, both of which are operatively coupled with the integrated unit.
[0056] The RCBO of the present disclosure is technically and logically different form the existing RCBOs in that, the RCBO of the present disclosure is compact in nature and the compactness is achieved by shifting/re-locating the RCD solenoid winding coil at MCB magnetic section and the MCB coil wind is moved on RCD solenoid winding coil. Further, the conventional RCBOs require two solenoids are getting used i.e. one for tripping in case of Earth leakage and second one for tripping in case of short circuit, as there are two solenoids hence numbers of components like magnetic core, hammer, trip pin, resetting spring are increased and finally assembly time /cost of product increased and whole design is complicated. To overcome all these issues the present disclosure eliminates earth leakage side solenoid bobbin and related tripping mechanism and shifts/re-locates/re-arranges the RCD solenoid winding at MCB magnetic section and the MCB coil is provided on RCD solenoid winding, due to there will be one tripping mechanism and one solenoid coil.
[0057] Various objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like features.
[0058] In order to understand the changes and development in the proposed RCBO as compared to the conventional RCBO, referring again to FIG.1 wherein a cut away view of conventional RCBO with various components and their arrangement there within and their working, as available in the prior-art is illustrated.
[0059] As shown in FIG. 1, the MCB 102 portion can include the MCB 102 components of the RCBO, and the RCD 104 portion can include the RCD components of the RCBO. The MCB components can include a fixed contact 106, a moving contact 108, an MCB magnetic winding (coil) 110, and a switching mechanism (mechanical linkage) 112. Further, there can be mainly one bi-metallic strip, and one hand operated on-off lever. The RCD components can include a RCD solenoid winding (coil) 114 over the solenoid bobbin 124, wires connected to PCB 116, a neutral primary 118, a Current Balanced Core Transformer (CBCT) mounted on PCB 120, a phase primary 122. The neutral primary 118 and the phase primary 122 wires are connected through RCD. The conventional RCBO 100 also include a trip pin (connecting link) 126 which connects the RCD solenoid coil plunger128 and the switching mechanism (mechanical linkage) 112.
[0060] In normal condition, the MCB 102 works as switch. In exemplary working, if MCB 102 is overloaded the bi-metallic strip becomes over heated and deformed. This deformation of bi-metallic strip causes displacement of latch point. The moving contact 108 of the MCB is so arranged by means of spring pressure, with this latch point, that a little displacement of latch causes, release of spring and makes the moving contact 108 to move for opening the MCB. The current coil or trip coil 126 is placed such a manner that during short circuit fault the magneto motive force (MMF) of that coil causes its plunger to hit the same latch point and make the latch to be displaced. Hence the MCB 102 will open in same manner. When operating lever of the MCB is operated by hand, that means when user makes the MCB at off position manually, the same latch point is displaced as a result moving contact 108 separated from fixed contact 106 in same manner. When the moving contact 108 separated from fixed contact 106, there may be a high chance of arc. This arc then goes up through the arc runner and enters into arc splitters and is finally quenched. When user switch on an MCB 102, user actually reset the displaced operating latch to its previous on position and make the MCB 102 ready for another switch off or trip operation.
[0061] In exemplary working of the RCD, the amount of current flows through the phase primary 122. Current difference between phase primary 122 and neutral primary 118 detect by RCD 104 through CBCT 120 in residual current device having a trip mechanism for isolating an electric supply to an electrical installation upon detection of a predetermined current imbalance between the line and neutral conductors of said electric supply. Further, the RCD solenoid winding (coil) 114 contains a compressed spring and plunger 128, which can be released by a relatively small amount of energy. This can produce enough force to trip the main mechanism which itself stores energy in springs when the Trip pin 126 is pushed to open the contacts.
[0062] Generally when any earth leakage occurs in the equipment, there may be part of phase current passes to the earth, through the leakage path instead of returning via neutral wire 118 Hence the magnitude of the neutral current passing through RCBO is not equal to phase current passing through it. When such current difference crosses a predetermined value, generated voltage in CBCT 116 secondary winding acts as gate pulse to TRIAC and TRIAC become conductive and passes rated voltage to RCD solenoid coli 114 which operates the switching mechanism disconnects the power supply to the instrument under protection. It is required that to operate the electronic components PCB is to be always connected to supply voltage.
[0063] According to the present disclosure, as shown in FIG. 2, working principal is same as existing RCBO (FIG. 1) however the tripping signal (mechanical) is from one/single point i.e., MCB tripping mechanism. Using the MCB tripping mechanism according to the present disclosure, the electric trip signal (rated voltage) from the PCB passes through TRIAC which drive the magnetic trip assembly of MCB part as solenoid coil is shifted bellow MCB magnetic coil.
[0064] As can be clearly seen from the comparison of the FIG. 1 (prior-art) and the FIG. 2 (the proposed RCBO), the solenoid coil with RCD solenoid bobbin, solenoid spring, Hammer nut, Solenoid plunger and RCD moving core are completely removed, while the solenoid winding is shifted to MCB magnetic coil bobbin. Further, the trip pin (trip pin for RCD) for connecting switching mechanism of the MCB and the solenoid coil of the RCD as shown in FIG. 1) is removed, while new MCB release brass pin and hammer are added to the conventional RCBO.
[0065] In an embodiment, the new and improved proposed RCBO according to the present disclosure provides and alternate way to eliminate the de latching and make RCD assembly / tripping mechanism simplified.
[0066] In an embodiment, FIG. 2 illustrates an exemplary cut-away view of a first face of modified RCBO in an exemplary embodiment of the system disclosed. As shown, the MCB 102 portion includes include the fixed contact 106, the moving contact 108, the MCB magnetic winding (coil) 110, and the switching mechanism (mechanical linkage) 112 as available in the prior-art. However, a new component i.e., Solenoid coil connected to PCB at solenoid soldering point 202 is added/included in the MCB 102 portion as compared to the conventional RCBO.
[0067] Further, as shown the RCD 102 can include the neutral primary 118, Core Balanced Current Transformer (CBCT) mounted on PCB, the phase primary 122, as available in the prior-art. However, the RCD solenoid winding (coil) 114, wires connected to PCB 116, RCD solenoid bobbin 124, RCD solenoid coil 114 over the solenoid bobbin 124 are removed from the RCD 102 components. More specifically, according to the present disclosure, solenoid coil with RCD solenoid bobbin, solenoid spring, hammer nut, solenoid plunger and RCD moving core removed, whereas solenoid winding shifted to MCB magnetic coil bobbin. Further, the trip pin (connecting link) 126 which connects the RCD solenoid coil and the switching mechanism (mechanical linkage) 112 is also removed and MCB release brass pin and hammer added to the MCB 102 components.
[0068] It may be clearly noted that, the present disclosure provides a new RCBO with an integrated unit having a solenoid coil (also referred to as solenoid winding) and magnetic coil (also referred to as magnetic winding).
[0069] In an embodiment, in existing designs of RCBOs two solenoids are getting used i.e. one for tripping in case of earth leakage and second one for tripping in case of short circuit. As there are two solenoids used hence numbers of components increased like magnetic core, hammer, trip pin, resetting spring and finally assembly time /cost of product increased and whole design is complicated. To overcome all these issues the proposed RCBO eliminates earth leakage side solenoid bobbin, the related tripping mechanism, and the RCD solenoid winding (coil) is relocated/shifted at MCB magnetic section. Further, the MCB coil is placed on RCD solenoid winding, with this there will be one tripping mechanism and one solenoid coil.
[0070] In may be appreciated that, a single Core Balance Current Transformer (CBCT) can be a ring type current transformer through centre of which a three core cable or three single core cables of three phase system passes. In an example, a single CBCT can be used for earth fault protection in which phase and neutral cable can passes.
[0071] FIGs. 3A-3K illustrates the components that are removed/rearranged/restructured form the proposed RCBO and the components that are newly manufactured and used in proposed RCBO, in accordance with an exemplary embodiment of the proposed disclosure. To avoid the complexity in understanding the difference in the proposed RCBO and the conventional RCBO, FIG. 3A-3K shows only the components that are removed/rearranged/restructured form the proposed RCBO and the components that are newly manufactured and used in proposed RCBO. It would be appreciated that, the required other basic components of the proposed RCBO are similar to the conventional RCBO, unless otherwise explicitly mentioned in the present disclosure.
[0072] FIG. 3A illustrates a trip pin as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0073] FIG. 3B illustrates RCD solenoid bobbin as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0074] FIG. 3C illustrates RCD solenoid spring as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0075] FIG. 3D illustrates a hammer nut as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0076] FIG. 3E illustrates RCD solenoid plunger as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0077] FIG. 3F illustrates RCD moving core as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0078] FIG. 3F illustrates MCB sleeve is a new component that is manufacture/designed dedicatedly for the proposed RCBO and required for its working/operation. It may be appreciated that such sleeve can be manufactured / designed using any of the know techniques of fabrication and using any of the know materials for fabrication.
[0079] FIG. 3H illustrates release pin is a new component that is manufacture/designed dedicatedly for the proposed RCBO and required for its working/operation. It may be appreciated that such release pin can be manufactured / designed using any of the know techniques of fabrication and using any of the know materials for fabrication.
[0080] FIG. 3I illustrates hammer is a new component that is manufacture/designed dedicatedly for the proposed RCBO and required for its working/operation. It may be appreciated that such hammer can be manufactured / designed using any of the know techniques of fabrication and using any of the know materials for fabrication
[0081] FIG. 3J illustrates MCB sleeve as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0082] FIG. 3K illustrates RCD solenoid pin as available in the conventional RCBO but not used in the proposed RCBO (removed/rearranged/restructured component).
[0083] FIG. 4 illustrates placement of a RCD solenoid coil and a MCB coil in the proposed RCBO, in accordance with an exemplary embodiment of the proposed disclosure. As shown in FIG. 4, the a RCD solenoid coil 202 and a MCB coil 110 are provide at same location in MCB section and the solenoid bobbin 114 from the RCD section is removed.
[0084] FIG. 5 illustrates exemplary operating circuit for conventional RCBO as available in the prior-art. In the existing designs of RCBOs two solenoids are used i.e. one for tripping in case of earth leakage and second one for tripping in case of short circuit. As there are two solenoids used hence numbers of components increased like magnetic core, hammer, trip pin, resetting spring and finally assembly time /cost of product increased and whole design is complicated.
[0085] To overcome all these issues the proposed RCBO eliminates earth leakage side solenoid bobbin, the related tripping mechanism, and the RCD solenoid winding (coil) is relocated/shifted at MCB magnetic section. Further, the MCB coil is placed on RCD solenoid winding, with this there will be one tripping mechanism and one solenoid coil. FIG. 6 illustrates exemplary modified operating circuit for proposed RCBO, in accordance with an exemplary embodiment of the proposed disclosure.
[0086] In working, when any earth leakage occurs in the equipment (load) 502, there may be part of phase current passes to the earth, through the leakage path instead of returning via neutral primary 504. Hence the magnitude of the neutral current passing through RCBO is not equal to phase current passing through it. When this current difference crosses a predetermined value, generated voltage in CBCT 506 secondary winding 508 acts as gate pulse to TRIAC (PCB 510) and TRIAC become conductive and passes rated voltage (electrical signal) to RCD solenoid coli 512 which operates the switching mechanism (mechanical signal) disconnects the power supply to the instrument under protection by means of MCB magnetic coil 514.
[0087] In an implementation, according to the present disclosure, when any earth leakage occurs in the equipment (load) 502, there may be part of phase current passes to the earth, through the leakage path instead of returning via neutral primary 504. Hence the magnitude of the neutral current passing through RCBO is not equal to phase current passing through it. When this current difference crosses a predetermined value, generated voltage in CBCT 506 secondary winding 508 acts as gate pulse to TRIAC (PCB 510) and TRIAC become conductive and passes rated voltage (electrical signal) to an integrated unit 602 (new technical modifications) having a solenoid coil and magnetic coil which operates the switching mechanism (mechanical signal) disconnects the power supply to the instrument under protection.
[0088] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ….and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
[0089] While embodiments of the present disclosure have been illustrated and described, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

ADVANTAGES OF THE INVENTION
[0090] The present disclosure eliminates de-latching issue of RCD in conventional RCBOs.
[0091] The present disclosure reduces complexity of RCBO circuit by eliminating various components form the conventional RCD circuitry of conventional RCBOs such as but not limited to solenoid bobbin, hammer, earth leakage side trip pin, resetting spring.
[0092] The present disclosure provides a unique design of RCBO circuit by shifting RCD solenoid winding at MCB section and MCB coil wind on RCD solenoid winding
[0093] The present disclosure provides RCBO circuit with reduced components for earth leakage and overload current protection.