The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine protection circuit for under-voltage, over-voltage, and shunt release of the circuit breaker.
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] Under Voltage Release, Over Voltage Release and Shunt release
are used as an accessory device along with circuit breaker. Function of under voltage release (OV) is to protect system in the event of under voltage fault. Function of over voltage release (UV) is to protect system in the event of over voltage fault. Function of shunt release (SH) is to provide remote tripping of circuit breaker in order to isolate equipment/s from electrical system. At present all the under voltage (UV), over voltage (OV) and shunt release (SH) are three independent devices. There seems to be no combined solution for OV, UV and shunt Release.
[0004] There is, therefore, a need of an improved protection circuit that is
capable of performing in all the under voltage, over voltage, and shunt release function for a circuit breaker.
OBJECTS OF THE PRESENT DISCLOSURE
[0005] Some of the objects of the present disclosure, which at least one
embodiment herein satisfies are as listed herein below.
[0006] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is capable of performing under voltage release, over voltage release, and shunt release.

[0007] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is efficient.
[0008] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is cost effective.
SUMMARY
[0009] The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine protection circuit for under-voltage, over-voltage, and shunt release of the circuit breaker.
[0010] An aspect of the present disclosure pertains to a protection circuit
for circuit breaker. The protection circuit includes an electromagnetic coil
electrically configured with circuit breaker. A first circuit electrically configured
with the electromagnetic coil, and the first circuit is configured to trip the circuit
breaker when an input voltage is below a first predefined value. A switching
circuit electrically configured with the first circuit. A second circuit electrically
configured, through the switching circuit, with the first circuit, and the second
circuit is configured to trip the circuit breaker when the input voltage is greater
than a second pre-defined value. A third circuit optically configured with the
switching circuit, and configured to trip, through the switching circuit, the circuit
breaker when the input voltage is applied to input terminals of the third circuit.
[0011] In an aspect, the second pre-defined value may be greater than the
first pre-defined value.
[0012] In an aspect, the switching circuit may comprise a power device,
and a resistor.
[0013] In an aspect, the first circuit may comprise a first rectifier, a first
clipping circuit, and a first voltage divider.
[0014] In an aspect, when the input voltage is less than the first pre-
defined value, a first voltage "VI" across the first clipping circuit may become lower than a first reverse voltage of the first clipping circuit causing electrical

open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
[0015] In an aspect, the second circuit may comprise a second rectifier, a
second clipping circuit, and a second voltage divider.
[0016] In an aspect, when the input voltage is greater than the second pre-
defined value, a second voltage "V2" across the second clipping circuit may become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0017] In an aspect, the third circuit may comprise a third rectifier, a third
clipping circuit, and a third voltage divider.
[0018] In an aspect, when the input voltage is applied to the input
terminals of the third circuit, a voltage "V3" across the third rectifier may become higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0019] 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
[0020] 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. The diagrams are for illustration only, which thus is not a limitation of the present disclosure.

[0021] 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.
[0022] FIG. 1A-C illustrates exemplary representation of a protection
circuit for a circuit breaker, in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION
[0023] 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 scope of the present disclosure as defined by the appended
claims.
[0024] In the following description, numerous specific details are set forth
in order to provide a thorough understanding of embodiments of the present
invention. It will be apparent to one skilled in the art that embodiments of the
present invention may be practiced without some of these specific details.
[0025] The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine
protection circuit for under-voltage, over-voltage, and shunt release of the circuit
breaker.
[0026] The present disclosure elaborates upon a protection circuit for
circuit breaker. The protection circuit includes an electromagnetic coil electrically
configured with circuit breaker. A first circuit electrically configured with the
electromagnetic coil, and the first circuit is configured to trip the circuit breaker

when an input voltage is below a first predefined value. A switching circuit
electrically configured with the first circuit. A second circuit electrically
configured, through the switching circuit, with the first circuit, and the second
circuit is configured to trip the circuit breaker when the input voltage is greater
than a second pre-defined value. A third circuit optically configured with the
switching circuit, and configured to trip, through the switching circuit, the circuit
breaker when the input voltage is applied to input terminals of the third circuit.
[0027] In an embodiment, the second pre-defined value can be greater
than the first pre-defined value.
[0028] In an embodiment, the switching circuit can comprise a power
device, and a resistor.
[0029] In an embodiment, the first circuit can comprise a first rectifier, a
first clipping circuit, and a first voltage divider.
[0030] In an embodiment, when the input voltage is less than the first pre-
defined value, a first voltage "VI" across the first clipping circuit can become lower than a first reverse voltage of the first clipping circuit causing electrical open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
[0031] In an embodiment, the second circuit can comprise a second
rectifier, a second clipping circuit, and a second voltage divider.
[0032] In an embodiment, when the input voltage is greater than the
second pre-defined value, a second voltage "V2" across the second clipping circuit can become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0033] In an embodiment, the third circuit can comprise a third rectifier, a
third clipping circuit, and a third voltage divider.
[0034] In an embodiment, when the input voltage is applied to the input
terminals of the third circuit, a voltage "V3" across the third rectifier can become higher than a third reverse voltage of the third rectifier leasing to electrical close

of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0035] FIG. 1A-C illustrates exemplary representation of a protection
circuit for a circuit breaker, in accordance with an embodiment of the present disclosure.
[0036] As illustrated, a protection circuit 100 for a circuit breaker can
includes an electromagnetic coil 102 electrically configured with circuit breaker.
A first circuit 104 can be electrically configured with the electromagnetic coil
102. The first circuit 104 can be configured to trip the circuit breaker when an
input voltage is below a first predefined value. A switching circuit 110 can be
electrically configured with the first circuit 104. A second circuit 106 can be
electrically configured with the first circuit 104 through the switching circuit 110.
and the second circuit is configured to trip the circuit breaker when the input
voltage is greater than a second pre-defined value. A third circuit 108 can be
optically configured with the switching circuit 110 through an optocoupler 112.
The third circuit 108 can be configured to trip the circuit breaker when the input
voltage is applied to input terminals of the third circuit 108.
[0037] In an embodiment, the first circuit 104 can includes a first rectifier
"Dl", a first clipping circuit, and a first voltage divider. The first clipping circuit can include but not limited to a first Zener diode "DZ1" and the first voltage divider includes resistors "Rl" and "R2". The second circuit 106 can include a second rectifier that can be a diode "D2", a second clipping circuit, and a second voltage divider. The second clipping circuit can include but not limited to a second Zener diode "DZ2", and the second voltage divider can include resistors "R5" and "R6". The third circuit 108 can comprise a third rectifier "D4-D6" (can also referred as bridge rectifier), a third clipping circuit, and a third voltage divider. The third clipping circuit can include a third Zener diode "DZ3", and the third voltage divider can include resistors "R7" and "R13". The switching circuit 104 can include a power device 104-1 such as but not limited to a silicon control rectifier (SCR), and a resistor 104-2.

[0038] In an embodiment, the first circuit 104, the second circuit 106, and
the third circuit 108 can be provided with the input voltage that is an AC voltage, the second pre-defined value can be greater than the first pre-defined value. The first pre-defined value can be but not limited to a 30%-40% of the input voltage. The second pre-defined value can be 110%-120% of the input voltage. The input terminals of the third circuit 108 can alternatively be input with a DC voltage. In case of AC input voltage, the input terminals can input terminals of a bridge rectifier. The second pre-defined value/voltage is greater than the first pre-defined voltage/value.
[0039] In an embodiment, the electromagnetic coil 102 can be configured
with the circuit breaker through a movable plunger. When a voltage "VI" across the first Zener diode "DZl" is greater than a first reverse voltage of the first Zener diode "DZl", the first Zener diode can be reverse biased and can be in electrically closed condition. In this case the electromagnetic coil can be energized, and the movable plunger of the electromagnetic coil can be in latched condition and the circuit breaker can be in "ON" condition. When the voltage "VI" across the first Zener diode "DZl" is less or lower than a first reverse voltage of the first Zener diode "DZl", the first Zener diode can be in electrically OFF condition. In this case the electromagnetic coil can be de-energized, and the movable plunger of the electromagnetic coil can be in de-latched condition and the circuit breaker can be in "OFF" condition.
[0040] In an embodiment, when the input voltage is less than the first pre-
defined value (under-voltage condition), a first voltage "VI" across the first clipping circuit "DZl" can become lower than a first reverse voltage of the first clipping circuit "DZl" causing electrical open of the first clipping circuit "DZl" facilitating de-energizing of the electromagnetic coil 102 for tripping the circuit breaker. When the input voltage again becomes higher than the first pre-defined value, the first Zener diode "DZl" can be electrical closed facilitating energizing of the electromagnetic coil 102 and the movable plunger can again be in latched condition.

[0041] In an embodiment, when the input voltage is greater than the
second pre-defined value (over-voltage condition), a second voltage "V2" across the second clipping circuit can become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage. When the input voltage becomes less than the second pre-defined value, the second Zener diode "DZ2" can go in electrically OFF condition leading to non-triggering of the SCR, and energizing of the electromagnetic coil 102 can lead to latched condition of the movable plunger.
[0042] In an embodiment, when the input voltage is applied to the input
terminals of the third circuit (shunt condition), a voltage "V3" across the third rectifier can become higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0043] Moreover, in interpreting the specification, 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 refer 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.
[0044] 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
[0045] The proposed invention provides a protection circuit for a circuit
breaker, which is capable of performing under voltage release, over voltage
release, and shunt release.
[0046] The proposed invention provides a protection circuit for a circuit
breaker, which is efficient.
[0047] The proposed invention provides a protection circuit for a circuit
breaker, which is cost effective.

We Claim:

1. A protection circuit for circuit breaker, the circuit comprising;
an electromagnetic coil electrically configured with circuit breaker;
a first circuit electrically configured with the electromagnetic coil, wherein the first circuit is configured to trip the circuit breaker when an input voltage is below a first predefined value;
a switching circuit electrically configured with the first circuit;
a second circuit electrically configured, through the switching circuit, with the first circuit, wherein the second circuit is configured to trip the circuit breaker when the input voltage is greater than a second pre-defined value; and
a third circuit optically configured with the switching circuit, and configured to trip, through the switching circuit, the circuit breaker when the input voltage is applied to input terminals of the third circuit.
2. The protection circuit as claimed in claim 1, wherein the second pre¬defined value is greater than the first pre-defined value.
3. The protection circuit as claimed in claim 1, wherein the switching circuit comprises a power device, and a resistor.
4. The protection circuit as claimed in claim 1, wherein the first circuit comprises a first rectifier, a first clipping circuit, and a first voltage divider.
5. The protection circuit as claimed in claim 4, wherein when the input voltage is less than the first pre-defined value, a first voltage "VI" across the first clipping circuit becomes lower than a first reverse voltage of the first clipping circuit causing electrical open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
6. The protection circuit as claimed in claim 1, wherein the second circuit comprises a second rectifier, a second clipping circuit, and a second voltage divider.

7. The protection circuit as claimed in claim 6, wherein when the input voltage is greater than the second pre-defined value, a second voltage "V2" across the second clipping circuit becomes higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
8. The protection circuit as claimed in claim 1, wherein the third circuit comprises a third rectifier, a third clipping circuit, and a third voltage divider.
9. The protection circuit as claimed in claim 8, wherein when the input voltage is applied to the input terminals of the third circuit, a voltage "V3" across the third rectifier becomes higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine protection circuit for under-voltage, over-voltage, and shunt release of the circuit breaker.
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] Under Voltage Release, Over Voltage Release and Shunt release
are used as an accessory device along with circuit breaker. Function of under voltage release (OV) is to protect system in the event of under voltage fault. Function of over voltage release (UV) is to protect system in the event of over voltage fault. Function of shunt release (SH) is to provide remote tripping of circuit breaker in order to isolate equipment/s from electrical system. At present all the under voltage (UV), over voltage (OV) and shunt release (SH) are three independent devices. There seems to be no combined solution for OV, UV and shunt Release.
[0004] There is, therefore, a need of an improved protection circuit that is
capable of performing in all the under voltage, over voltage, and shunt release function for a circuit breaker.
OBJECTS OF THE PRESENT DISCLOSURE
[0005] Some of the objects of the present disclosure, which at least one
embodiment herein satisfies are as listed herein below.
[0006] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is capable of performing under voltage release, over voltage release, and shunt release.

[0007] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is efficient.
[0008] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is cost effective.
SUMMARY
[0009] The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine protection circuit for under-voltage, over-voltage, and shunt release of the circuit breaker.
[0010] An aspect of the present disclosure pertains to a protection circuit
for circuit breaker. The protection circuit includes an electromagnetic coil
electrically configured with circuit breaker. A first circuit electrically configured
with the electromagnetic coil, and the first circuit is configured to trip the circuit
breaker when an input voltage is below a first predefined value. A switching
circuit electrically configured with the first circuit. A second circuit electrically
configured, through the switching circuit, with the first circuit, and the second
circuit is configured to trip the circuit breaker when the input voltage is greater
than a second pre-defined value. A third circuit optically configured with the
switching circuit, and configured to trip, through the switching circuit, the circuit
breaker when the input voltage is applied to input terminals of the third circuit.
[0011] In an aspect, the second pre-defined value may be greater than the
first pre-defined value.
[0012] In an aspect, the switching circuit may comprise a power device,
and a resistor.
[0013] In an aspect, the first circuit may comprise a first rectifier, a first
clipping circuit, and a first voltage divider.
[0014] In an aspect, when the input voltage is less than the first pre-
defined value, a first voltage "VI" across the first clipping circuit may become lower than a first reverse voltage of the first clipping circuit causing electrical

open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
[0015] In an aspect, the second circuit may comprise a second rectifier, a
second clipping circuit, and a second voltage divider.
[0016] In an aspect, when the input voltage is greater than the second pre-
defined value, a second voltage "V2" across the second clipping circuit may become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0017] In an aspect, the third circuit may comprise a third rectifier, a third
clipping circuit, and a third voltage divider.
[0018] In an aspect, when the input voltage is applied to the input
terminals of the third circuit, a voltage "V3" across the third rectifier may become higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0019] 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
[0020] 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. The diagrams are for illustration only, which thus is not a limitation of the present disclosure.

[0021] 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.
[0022] FIG. 1A-C illustrates exemplary representation of a protection
circuit for a circuit breaker, in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION
[0023] 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 scope of the present disclosure as defined by the appended
claims.
[0024] In the following description, numerous specific details are set forth
in order to provide a thorough understanding of embodiments of the present
invention. It will be apparent to one skilled in the art that embodiments of the
present invention may be practiced without some of these specific details.
[0025] The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine
protection circuit for under-voltage, over-voltage, and shunt release of the circuit
breaker.
[0026] The present disclosure elaborates upon a protection circuit for
circuit breaker. The protection circuit includes an electromagnetic coil electrically
configured with circuit breaker. A first circuit electrically configured with the
electromagnetic coil, and the first circuit is configured to trip the circuit breaker

when an input voltage is below a first predefined value. A switching circuit
electrically configured with the first circuit. A second circuit electrically
configured, through the switching circuit, with the first circuit, and the second
circuit is configured to trip the circuit breaker when the input voltage is greater
than a second pre-defined value. A third circuit optically configured with the
switching circuit, and configured to trip, through the switching circuit, the circuit
breaker when the input voltage is applied to input terminals of the third circuit.
[0027] In an embodiment, the second pre-defined value can be greater
than the first pre-defined value.
[0028] In an embodiment, the switching circuit can comprise a power
device, and a resistor.
[0029] In an embodiment, the first circuit can comprise a first rectifier, a
first clipping circuit, and a first voltage divider.
[0030] In an embodiment, when the input voltage is less than the first pre-
defined value, a first voltage "VI" across the first clipping circuit can become lower than a first reverse voltage of the first clipping circuit causing electrical open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
[0031] In an embodiment, the second circuit can comprise a second
rectifier, a second clipping circuit, and a second voltage divider.
[0032] In an embodiment, when the input voltage is greater than the
second pre-defined value, a second voltage "V2" across the second clipping circuit can become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0033] In an embodiment, the third circuit can comprise a third rectifier, a
third clipping circuit, and a third voltage divider.
[0034] In an embodiment, when the input voltage is applied to the input
terminals of the third circuit, a voltage "V3" across the third rectifier can become higher than a third reverse voltage of the third rectifier leasing to electrical close

of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0035] FIG. 1A-C illustrates exemplary representation of a protection
circuit for a circuit breaker, in accordance with an embodiment of the present disclosure.
[0036] As illustrated, a protection circuit 100 for a circuit breaker can
includes an electromagnetic coil 102 electrically configured with circuit breaker.
A first circuit 104 can be electrically configured with the electromagnetic coil
102. The first circuit 104 can be configured to trip the circuit breaker when an
input voltage is below a first predefined value. A switching circuit 110 can be
electrically configured with the first circuit 104. A second circuit 106 can be
electrically configured with the first circuit 104 through the switching circuit 110.
and the second circuit is configured to trip the circuit breaker when the input
voltage is greater than a second pre-defined value. A third circuit 108 can be
optically configured with the switching circuit 110 through an optocoupler 112.
The third circuit 108 can be configured to trip the circuit breaker when the input
voltage is applied to input terminals of the third circuit 108.
[0037] In an embodiment, the first circuit 104 can includes a first rectifier
"Dl", a first clipping circuit, and a first voltage divider. The first clipping circuit can include but not limited to a first Zener diode "DZ1" and the first voltage divider includes resistors "Rl" and "R2". The second circuit 106 can include a second rectifier that can be a diode "D2", a second clipping circuit, and a second voltage divider. The second clipping circuit can include but not limited to a second Zener diode "DZ2", and the second voltage divider can include resistors "R5" and "R6". The third circuit 108 can comprise a third rectifier "D4-D6" (can also referred as bridge rectifier), a third clipping circuit, and a third voltage divider. The third clipping circuit can include a third Zener diode "DZ3", and the third voltage divider can include resistors "R7" and "R13". The switching circuit 104 can include a power device 104-1 such as but not limited to a silicon control rectifier (SCR), and a resistor 104-2.

[0038] In an embodiment, the first circuit 104, the second circuit 106, and
the third circuit 108 can be provided with the input voltage that is an AC voltage, the second pre-defined value can be greater than the first pre-defined value. The first pre-defined value can be but not limited to a 30%-40% of the input voltage. The second pre-defined value can be 110%-120% of the input voltage. The input terminals of the third circuit 108 can alternatively be input with a DC voltage. In case of AC input voltage, the input terminals can input terminals of a bridge rectifier. The second pre-defined value/voltage is greater than the first pre-defined voltage/value.
[0039] In an embodiment, the electromagnetic coil 102 can be configured
with the circuit breaker through a movable plunger. When a voltage "VI" across the first Zener diode "DZl" is greater than a first reverse voltage of the first Zener diode "DZl", the first Zener diode can be reverse biased and can be in electrically closed condition. In this case the electromagnetic coil can be energized, and the movable plunger of the electromagnetic coil can be in latched condition and the circuit breaker can be in "ON" condition. When the voltage "VI" across the first Zener diode "DZl" is less or lower than a first reverse voltage of the first Zener diode "DZl", the first Zener diode can be in electrically OFF condition. In this case the electromagnetic coil can be de-energized, and the movable plunger of the electromagnetic coil can be in de-latched condition and the circuit breaker can be in "OFF" condition.
[0040] In an embodiment, when the input voltage is less than the first pre-
defined value (under-voltage condition), a first voltage "VI" across the first clipping circuit "DZl" can become lower than a first reverse voltage of the first clipping circuit "DZl" causing electrical open of the first clipping circuit "DZl" facilitating de-energizing of the electromagnetic coil 102 for tripping the circuit breaker. When the input voltage again becomes higher than the first pre-defined value, the first Zener diode "DZl" can be electrical closed facilitating energizing of the electromagnetic coil 102 and the movable plunger can again be in latched condition.

[0041] In an embodiment, when the input voltage is greater than the
second pre-defined value (over-voltage condition), a second voltage "V2" across the second clipping circuit can become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage. When the input voltage becomes less than the second pre-defined value, the second Zener diode "DZ2" can go in electrically OFF condition leading to non-triggering of the SCR, and energizing of the electromagnetic coil 102 can lead to latched condition of the movable plunger.
[0042] In an embodiment, when the input voltage is applied to the input
terminals of the third circuit (shunt condition), a voltage "V3" across the third rectifier can become higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0043] Moreover, in interpreting the specification, 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 refer 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.
[0044] 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
[0045] The proposed invention provides a protection circuit for a circuit
breaker, which is capable of performing under voltage release, over voltage
release, and shunt release.
[0046] The proposed invention provides a protection circuit for a circuit
breaker, which is efficient.
[0047] The proposed invention provides a protection circuit for a circuit
breaker, which is cost effective.

We Claim:
1. A protection circuit for circuit breaker, the circuit comprising;
an electromagnetic coil electrically configured with circuit breaker;
a first circuit electrically configured with the electromagnetic coil, wherein the first circuit is configured to trip the circuit breaker when an input voltage is below a first predefined value;
a switching circuit electrically configured with the first circuit;
a second circuit electrically configured, through the switching circuit, with the first circuit, wherein the second circuit is configured to trip the circuit breaker when the input voltage is greater than a second pre-defined value; and
a third circuit optically configured with the switching circuit, and configured to trip, through the switching circuit, the circuit breaker when the input voltage is applied to input terminals of the third circuit.
2. The protection circuit as claimed in claim 1, wherein the second pre¬defined value is greater than the first pre-defined value.
3. The protection circuit as claimed in claim 1, wherein the switching circuit comprises a power device, and a resistor.
4. The protection circuit as claimed in claim 1, wherein the first circuit comprises a first rectifier, a first clipping circuit, and a first voltage divider.
5. The protection circuit as claimed in claim 4, wherein when the input voltage is less than the first pre-defined value, a first voltage "VI" across the first clipping circuit becomes lower than a first reverse voltage of the first clipping circuit causing electrical open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
6. The protection circuit as claimed in claim 1, wherein the second circuit comprises a second rectifier, a second clipping circuit, and a second voltage divider.

7. The protection circuit as claimed in claim 6, wherein when the input voltage is greater than the second pre-defined value, a second voltage "V2" across the second clipping circuit becomes higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
8. The protection circuit as claimed in claim 1, wherein the third circuit comprises a third rectifier, a third clipping circuit, and a third voltage divider.
9. The protection circuit as claimed in claim 8, wherein when the input voltage is applied to the input terminals of the third circuit, a voltage "V3" across the third rectifier becomes higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine protection circuit for under-voltage, over-voltage, and shunt release of the circuit breaker.
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] Under Voltage Release, Over Voltage Release and Shunt release
are used as an accessory device along with circuit breaker. Function of under voltage release (OV) is to protect system in the event of under voltage fault. Function of over voltage release (UV) is to protect system in the event of over voltage fault. Function of shunt release (SH) is to provide remote tripping of circuit breaker in order to isolate equipment/s from electrical system. At present all the under voltage (UV), over voltage (OV) and shunt release (SH) are three independent devices. There seems to be no combined solution for OV, UV and shunt Release.
[0004] There is, therefore, a need of an improved protection circuit that is
capable of performing in all the under voltage, over voltage, and shunt release function for a circuit breaker.
OBJECTS OF THE PRESENT DISCLOSURE
[0005] Some of the objects of the present disclosure, which at least one
embodiment herein satisfies are as listed herein below.
[0006] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is capable of performing under voltage release, over voltage release, and shunt release.

[0007] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is efficient.
[0008] It is an object of the present disclosure to provide a protection
circuit for a circuit breaker, which is cost effective.
SUMMARY
[0009] The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine protection circuit for under-voltage, over-voltage, and shunt release of the circuit breaker.
[0010] An aspect of the present disclosure pertains to a protection circuit
for circuit breaker. The protection circuit includes an electromagnetic coil
electrically configured with circuit breaker. A first circuit electrically configured
with the electromagnetic coil, and the first circuit is configured to trip the circuit
breaker when an input voltage is below a first predefined value. A switching
circuit electrically configured with the first circuit. A second circuit electrically
configured, through the switching circuit, with the first circuit, and the second
circuit is configured to trip the circuit breaker when the input voltage is greater
than a second pre-defined value. A third circuit optically configured with the
switching circuit, and configured to trip, through the switching circuit, the circuit
breaker when the input voltage is applied to input terminals of the third circuit.
[0011] In an aspect, the second pre-defined value may be greater than the
first pre-defined value.
[0012] In an aspect, the switching circuit may comprise a power device,
and a resistor.
[0013] In an aspect, the first circuit may comprise a first rectifier, a first
clipping circuit, and a first voltage divider.
[0014] In an aspect, when the input voltage is less than the first pre-
defined value, a first voltage "VI" across the first clipping circuit may become lower than a first reverse voltage of the first clipping circuit causing electrical

open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
[0015] In an aspect, the second circuit may comprise a second rectifier, a
second clipping circuit, and a second voltage divider.
[0016] In an aspect, when the input voltage is greater than the second pre-
defined value, a second voltage "V2" across the second clipping circuit may become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0017] In an aspect, the third circuit may comprise a third rectifier, a third
clipping circuit, and a third voltage divider.
[0018] In an aspect, when the input voltage is applied to the input
terminals of the third circuit, a voltage "V3" across the third rectifier may become higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0019] 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
[0020] 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. The diagrams are for illustration only, which thus is not a limitation of the present disclosure.

[0021] 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.
[0022] FIG. 1A-C illustrates exemplary representation of a protection
circuit for a circuit breaker, in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION
[0023] 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 scope of the present disclosure as defined by the appended
claims.
[0024] In the following description, numerous specific details are set forth
in order to provide a thorough understanding of embodiments of the present
invention. It will be apparent to one skilled in the art that embodiments of the
present invention may be practiced without some of these specific details.
[0025] The present disclosure relates to the field of protection circuit for
circuit breaker. More particularly the present disclosure relates to a combine
protection circuit for under-voltage, over-voltage, and shunt release of the circuit
breaker.
[0026] The present disclosure elaborates upon a protection circuit for
circuit breaker. The protection circuit includes an electromagnetic coil electrically
configured with circuit breaker. A first circuit electrically configured with the
electromagnetic coil, and the first circuit is configured to trip the circuit breaker

when an input voltage is below a first predefined value. A switching circuit
electrically configured with the first circuit. A second circuit electrically
configured, through the switching circuit, with the first circuit, and the second
circuit is configured to trip the circuit breaker when the input voltage is greater
than a second pre-defined value. A third circuit optically configured with the
switching circuit, and configured to trip, through the switching circuit, the circuit
breaker when the input voltage is applied to input terminals of the third circuit.
[0027] In an embodiment, the second pre-defined value can be greater
than the first pre-defined value.
[0028] In an embodiment, the switching circuit can comprise a power
device, and a resistor.
[0029] In an embodiment, the first circuit can comprise a first rectifier, a
first clipping circuit, and a first voltage divider.
[0030] In an embodiment, when the input voltage is less than the first pre-
defined value, a first voltage "VI" across the first clipping circuit can become lower than a first reverse voltage of the first clipping circuit causing electrical open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
[0031] In an embodiment, the second circuit can comprise a second
rectifier, a second clipping circuit, and a second voltage divider.
[0032] In an embodiment, when the input voltage is greater than the
second pre-defined value, a second voltage "V2" across the second clipping circuit can become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0033] In an embodiment, the third circuit can comprise a third rectifier, a
third clipping circuit, and a third voltage divider.
[0034] In an embodiment, when the input voltage is applied to the input
terminals of the third circuit, a voltage "V3" across the third rectifier can become higher than a third reverse voltage of the third rectifier leasing to electrical close

of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0035] FIG. 1A-C illustrates exemplary representation of a protection
circuit for a circuit breaker, in accordance with an embodiment of the present disclosure.
[0036] As illustrated, a protection circuit 100 for a circuit breaker can
includes an electromagnetic coil 102 electrically configured with circuit breaker.
A first circuit 104 can be electrically configured with the electromagnetic coil
102. The first circuit 104 can be configured to trip the circuit breaker when an
input voltage is below a first predefined value. A switching circuit 110 can be
electrically configured with the first circuit 104. A second circuit 106 can be
electrically configured with the first circuit 104 through the switching circuit 110.
and the second circuit is configured to trip the circuit breaker when the input
voltage is greater than a second pre-defined value. A third circuit 108 can be
optically configured with the switching circuit 110 through an optocoupler 112.
The third circuit 108 can be configured to trip the circuit breaker when the input
voltage is applied to input terminals of the third circuit 108.
[0037] In an embodiment, the first circuit 104 can includes a first rectifier
"Dl", a first clipping circuit, and a first voltage divider. The first clipping circuit can include but not limited to a first Zener diode "DZ1" and the first voltage divider includes resistors "Rl" and "R2". The second circuit 106 can include a second rectifier that can be a diode "D2", a second clipping circuit, and a second voltage divider. The second clipping circuit can include but not limited to a second Zener diode "DZ2", and the second voltage divider can include resistors "R5" and "R6". The third circuit 108 can comprise a third rectifier "D4-D6" (can also referred as bridge rectifier), a third clipping circuit, and a third voltage divider. The third clipping circuit can include a third Zener diode "DZ3", and the third voltage divider can include resistors "R7" and "R13". The switching circuit 104 can include a power device 104-1 such as but not limited to a silicon control rectifier (SCR), and a resistor 104-2.

[0038] In an embodiment, the first circuit 104, the second circuit 106, and
the third circuit 108 can be provided with the input voltage that is an AC voltage, the second pre-defined value can be greater than the first pre-defined value. The first pre-defined value can be but not limited to a 30%-40% of the input voltage. The second pre-defined value can be 110%-120% of the input voltage. The input terminals of the third circuit 108 can alternatively be input with a DC voltage. In case of AC input voltage, the input terminals can input terminals of a bridge rectifier. The second pre-defined value/voltage is greater than the first pre-defined voltage/value.
[0039] In an embodiment, the electromagnetic coil 102 can be configured
with the circuit breaker through a movable plunger. When a voltage "VI" across the first Zener diode "DZl" is greater than a first reverse voltage of the first Zener diode "DZl", the first Zener diode can be reverse biased and can be in electrically closed condition. In this case the electromagnetic coil can be energized, and the movable plunger of the electromagnetic coil can be in latched condition and the circuit breaker can be in "ON" condition. When the voltage "VI" across the first Zener diode "DZl" is less or lower than a first reverse voltage of the first Zener diode "DZl", the first Zener diode can be in electrically OFF condition. In this case the electromagnetic coil can be de-energized, and the movable plunger of the electromagnetic coil can be in de-latched condition and the circuit breaker can be in "OFF" condition.
[0040] In an embodiment, when the input voltage is less than the first pre-
defined value (under-voltage condition), a first voltage "VI" across the first clipping circuit "DZl" can become lower than a first reverse voltage of the first clipping circuit "DZl" causing electrical open of the first clipping circuit "DZl" facilitating de-energizing of the electromagnetic coil 102 for tripping the circuit breaker. When the input voltage again becomes higher than the first pre-defined value, the first Zener diode "DZl" can be electrical closed facilitating energizing of the electromagnetic coil 102 and the movable plunger can again be in latched condition.

[0041] In an embodiment, when the input voltage is greater than the
second pre-defined value (over-voltage condition), a second voltage "V2" across the second clipping circuit can become higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage. When the input voltage becomes less than the second pre-defined value, the second Zener diode "DZ2" can go in electrically OFF condition leading to non-triggering of the SCR, and energizing of the electromagnetic coil 102 can lead to latched condition of the movable plunger.
[0042] In an embodiment, when the input voltage is applied to the input
terminals of the third circuit (shunt condition), a voltage "V3" across the third rectifier can become higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
[0043] Moreover, in interpreting the specification, 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 refer 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.
[0044] 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
[0045] The proposed invention provides a protection circuit for a circuit
breaker, which is capable of performing under voltage release, over voltage
release, and shunt release.
[0046] The proposed invention provides a protection circuit for a circuit
breaker, which is efficient.
[0047] The proposed invention provides a protection circuit for a circuit
breaker, which is cost effective.

We Claim:
1. A protection circuit for circuit breaker, the circuit comprising;
an electromagnetic coil electrically configured with circuit breaker;
a first circuit electrically configured with the electromagnetic coil, wherein the first circuit is configured to trip the circuit breaker when an input voltage is below a first predefined value;
a switching circuit electrically configured with the first circuit;
a second circuit electrically configured, through the switching circuit, with the first circuit, wherein the second circuit is configured to trip the circuit breaker when the input voltage is greater than a second pre-defined value; and
a third circuit optically configured with the switching circuit, and configured to trip, through the switching circuit, the circuit breaker when the input voltage is applied to input terminals of the third circuit.
2. The protection circuit as claimed in claim 1, wherein the second pre¬defined value is greater than the first pre-defined value.
3. The protection circuit as claimed in claim 1, wherein the switching circuit comprises a power device, and a resistor.
4. The protection circuit as claimed in claim 1, wherein the first circuit comprises a first rectifier, a first clipping circuit, and a first voltage divider.
5. The protection circuit as claimed in claim 4, wherein when the input voltage is less than the first pre-defined value, a first voltage "VI" across the first clipping circuit becomes lower than a first reverse voltage of the first clipping circuit causing electrical open of the first clipping circuit facilitating de-energizing of the electromagnetic coil for tripping the circuit breaker.
6. The protection circuit as claimed in claim 1, wherein the second circuit comprises a second rectifier, a second clipping circuit, and a second voltage divider.

7. The protection circuit as claimed in claim 6, wherein when the input voltage is greater than the second pre-defined value, a second voltage "V2" across the second clipping circuit becomes higher than a second reverse voltage of the second clipping circuit causing electrical close of the second clipping circuit leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.
8. The protection circuit as claimed in claim 1, wherein the third circuit comprises a third rectifier, a third clipping circuit, and a third voltage divider.
9. The protection circuit as claimed in claim 8, wherein when the input voltage is applied to the input terminals of the third circuit, a voltage "V3" across the third rectifier becomes higher than a third reverse voltage of the third rectifier leasing to electrical close of the third clipper circuit further leading to triggering of the power device causing the voltage "VI" across the first rectifier becomes lower than the first reverse voltage.