Description:FIELD
The present invention generally relates to a field of electrical switches. Particularly, the present invention relates to the detection of a state of an electrical switch.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
An electrical switch is an electrical component that can disconnect or connect a conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. In case of any current spike, the electrical switch gets actuated to divert current spikes away from the electrical loads, thus preventing any damage to the load(s). Currently, electrical switches such as Miniature Circuit Breaker (MCB), isolators, Molded Case Circuit Breaker (MCCB) and the like are used. These electrical switches are mechanical switches and they are configured to actuate automatically in event of a voltage or current spike/fault. Once the electrical switch gets actuated, an operator is required to physically identify the actuated switch and reset the actuated switch to its normal operating position. However, it is a challenging task for the operator to physically monitor the electrical switches and further identify exactly which switch is actuated.
There is, therefore, felt a need to develop an apparatus for detecting a state of an electrical switch that alleviates the aforementioned disadvantages.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch.
Another object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch, which retrofits with the electrical switch.
Another object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch, which is compact.
Still another object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch which facilitates remote monitoring of the states of the electrical switch.
Yet another object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch, which fits on a DIN rail.
Another object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch which can be built into the electrical switch as an integrated unit.
Another object of the present disclosure is to provide an apparatus for detecting a state of an electrical switch, which retrofits with the electrical switch of any make, type and ampacity.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present invention envisages an apparatus for detecting a state of an electrical switch in an AC circuit. The apparatus comprises a first input terminal, a second input terminal, an AC-to-DC supply module, a sensing unit, a relay switch and a monitoring unit.
The first input terminal is connected to a first end of the electrical switch. The second input terminal is connected to a second end of the electrical switch.
The AC-to-DC supply module is connected to the first input terminal and is configured to receive AC supply from the AC circuit through the first input terminal. The AC-to-DC supply module comprises a first in-rush current limiting circuit, a first voltage regulator, and a first rectifying circuit. The first in-rush current limiting circuit is configured to limit an excess inflowing current of the AC supply from the first input terminal. The first voltage regulator is connected to the first in-rush current limiting circuit, the first voltage regulator is further configured to regulate a voltage of the AC supply to develop a constant voltage. The first rectifying circuit is configured to receive the developed voltage from the first voltage regulator, and is further configured to generate a DC supply of a predetermined voltage V1.
The sensing unit is connected to the second input terminal, the sensing unit is configured to receive a potential signal from the second end of the electrical switch via the second input terminal. The sensing unit comprises a second in-rush current limiting circuit, a second voltage regulator, a second rectifying circuit, a ripple filtering circuit and a Schmitt triggering circuit. The second in-rush current limiting circuit is configured to limit an excess inflowing current of the sensed potential signal. The second voltage regulator is connected to the second in-rush current limiting circuit and the second voltage regulator is configured to regulate the sensed potential signal. The second rectifying circuit is configured to receive the regulated potential signal from the second voltage regulator and is further configured to generate a DC signal of a predetermined voltage V2. The ripple filtering circuit is connected to the second rectifying circuit and is configured to remove ripples from the generated DC signal. The Schmitt triggering circuit is connected to the ripple filtering circuit and is configured to generate a triggering signal.
The relay switch is coupled to the AC-to-DC supply module and the sensing module. The relay switch is configured to receive DC supply from the AC-to-DC module and the triggering signal from the sensing module, wherein the relay switch is configured to actuate based on the received triggering signal, and is further configured to generate a detection signal indicating the state of the electrical switch.
In an embodiment, the apparatus retrofits with the electrical switch of the AC circuit.
The relay switch is a normally open switch or a normally closed switch. The generated triggering signal is high when the electrical switch state changes from an ON state to an OFF state. In another embodiment, the generated triggering signal is high when the electrical switch state changes from an OFF state to an ON state.
The first in-rush current limiting circuit consists of a resistor and two parallel capacitors, in a series configuration. The second in-rush current limiting circuit consists of a resistor and a capacitor, in a series configuration. The first and second voltage regulators are Zener diodes.
The first rectifying circuit comprises a diode and a first filtering capacitor. The diode is in a forward-biased configuration. The diode is configured to allow positive constant voltage developed across the first voltage regulator. The first filtering capacitor is configured to receive positive voltage from the diode, and to generate the DC supply of the predetermined voltage V1.
The second rectifying circuit comprises a diode and a second filtering capacitor. The diode is in a forward-biased configuration and the diode is configured to allow positive voltage of the regulated potential signal. The second filtering capacitor is configured to receive positive voltage from the diode, and to generate the DC signal of the predetermined voltage V2. In an embodiment, the second filtering capacitor has a capacitance of 1µF.
The ripple circuit comprises resistors and a capacitor. The resistors are connected to the second rectifying circuit, and the capacitor is connected between the resistor terminals.
The Schmitt trigger circuit is coupled with the AC-to-DC supply module through a resistor and the ripple circuit. The Schmitt trigger circuit comprises a first transistor, a second transistor and a feedback resistor. The ripple circuit is connected to the base of the first transistor, an emitter of the first transistor, one terminal of the resistor is connected to the base of the second transistor, and a feedback loop is formed between the base of the first transistor and a collector of the second transistor via the feedback resistor.
In an embodiment, the first and second voltage regulators, the AC-to-DC supply module, the sensing module, and the relay switch are connected via a common ground.
The AC-to-DC supply module includes an indicator circuit to indicate if DC supply is in accordance with the predetermined voltage, the indicator circuit comprises a resistor and a LED connected in a series configuration.
In an embodiment, the first and second input terminals, the first and second voltage regulators, the AC-to-DC supply module, the sensing module, and the relay switch are designed on a single Printed Circuit Board (PCB). The designed PCB is housed in a receptacle.
In an embodiment, the receptacle is configured to fit on a DIN rail.
In an embodiment, an electrical switch of an AC circuit comprises the apparatus.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
An apparatus for detecting a state of an electrical switch in an AC circuit of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1A illustrates an electrical switch changing its state from an ON state to an OFF state;
Figure 1B illustrates an electrical switch changing its state from an OFF state to an ON state; and
Figure 2 illustrates an electrical circuit diagram of an apparatus for detecting a state of an electrical switch present in an AC circuit, according to the present disclosure.
LIST OF REFERENCE NUMERALS USED IN THE DESCRIPTION AND DRAWING:
100 Apparatus
ES Electrical Switch
A First end of Electrical Switch
B Second end of Electrical Switch
C1, C2, C3, C4, C5, C6 Capacitors
D1, D2, D3 Diodes
GND Ground
L1, L2 Light Emitting Diodes (LED)
Q1, Q2 Transistors
R1, R2, R3, R4, R5, R6, R7, R8 Resistors
RLY Relay switch
Z1, Z2 Voltage regulators
T1 First input terminal
T2 Second input terminal
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises”, “comprising”, “including” and “having” are open-ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
When an element is referred to as being “mounted on”, “engaged to”, “connected to” or “coupled to” another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed elements.
The present invention envisages an apparatus 100 for detecting a state of an electrical switch (ES) in an AC circuit. The present disclosure is described with reference to Figure 1 and Figure 2.
Referring to Figures 1 and 2, the apparatus 100 comprises a first input terminal T1, a second input terminal T2, an AC-to-DC supply module, a sensing unit and a relay switch (RLY).
The first input terminal T1 is connected to a first end (A) of the electrical switch (ES). The second input terminal T2 is connected to a second end (B) of the electrical switch (ES).
The AC-to-DC supply module is connected to the first input terminal T1 and is configured to receive AC supply from the AC circuit through the first input terminal T1. The supply module comprises a first in-rush current limiting circuit, a first voltage regulator Z1, and a first rectifying circuit.
The first in-rush current limiting circuit is configured to limit an excess inflowing current of the AC supply from the first input terminal T1. The first in-rush current limiting circuit consists of a resistor R1 and two parallel capacitors (C1, C2), in a series configuration. In an embodiment, the first in-rush current limiting circuit consists of a resistor R1 and a single capacitor with a capacitance value equivalent to the capacitance value of the two parallel capacitors (C1, C2).
The first voltage regulator Z1 is connected to the first in-rush current limiting circuit. The first voltage regulator Z1 is further configured to regulate a voltage of the AC supply to develop a constant voltage. The first voltage regulator is a Zener diode Z1.
The first rectifying circuit is configured to receive the developed voltage from the first voltage regulator Z1, and is further configured to generate a DC supply of a predetermined voltage V1. The first rectifying circuit comprises a diode D1 and a first filtering capacitor C4. The diode D1 is in a forward-biased configuration. The diode D1 is configured to allow positive constant voltage developed across the first voltage regulator Z1. The first filtering capacitor C4 is configured to receive the positive voltage from the diode D1, and generates the DC supply of the predetermined voltage V1. In an embodiment, the predetermined voltage is 12V.
The sensing unit is connected to the second input terminal T2. The sensing unit is configured to receive a potential signal from the second end (B) of the electrical switch (ES) via the second input terminal T2. The sensing unit comprises a second in-rush current limiting circuit, a second voltage regulator Z2, a second rectifying circuit, a ripple filtering circuit and a Schmitt triggering circuit.
The second in-rush current limiting circuit is configured to limit an excess inflowing current of the sensed potential signal. The second in-rush current limiting circuit consists of a resistor R2 and a capacitor C3, in a series configuration.
The second voltage regulator Z2 is connected to the second in-rush current limiting circuit. The second voltage regulator Z2 is configured to regulate the sensed potential signal. The second voltage regulator is a Zener diode Z2.
The second rectifying circuit is configured to receive the regulated potential signal from the second voltage regulator Z2, and is further configured to generate a DC signal of a predetermined voltage V2. The second rectifying circuit comprises a diode D2 and a second filtering capacitor C5. The diode D2 is in a forward-biased configuration. The diode D2 is configured to allow positive voltage of the regulated potential signal. The second filtering capacitor C5 is configured to receive positive voltage from the diode D2, and to generate the DC signal of the predetermined voltage V2. In an embodiment the predetermined voltage V2 is 5V.
The ripple circuit comprises resistors (R4, R5) and a capacitor C6. The resistors (R4, R5) are connected to the second rectifying circuit, and the capacitor C6 is connected between the resistor (R4, R5) terminals. The ripple filtering circuit is connected to the second rectifying circuit to receive the generated DC signal. The ripple filtering circuit is configured to remove ripples from the generated DC signal.
The Schmitt trigger circuit is coupled with the AC-to-DC supply module through a resistor R7. The Schmitt trigger circuit comprises a first transistor Q1, a second transistor Q2 and a feedback resistor R6. The transistors (Q1, Q2) are Bipolar Junction Transistors (BJTs). The Schmitt triggering circuit is connected to the ripple filtering circuit, wherein the ripple circuit is connected to the base of the first transistor Q1. An emitter of the first transistor Q1 and one terminal of the resistor R7 is connected to the base of the second transistor Q2. A feedback loop is formed between the base of the first transistor Q1 and a collector of the second transistor Q2 via the feedback resistor R6. The Schmitt trigger circuit is configured to generate a triggering signal based on the received ripple-free DC signal.
The relay switch (RLY) is coupled to the AC-to-DC supply module and the sensing module. The relay switch (RLY) is configured to receive DC supply from the AC-to-DC module and the triggering signal from the sensing module. The relay switch (RLY) is configured to actuate based on the received triggering signal, and is further configured to generate a detection signal indicating the state of the electrical switch (ES). The relay switch is a normally open switch or a normally closed switch. The generated triggering signal is high when the electrical switch (ES) state changes from an ON state to an OFF state. In another embodiment the generated triggering signal is high when the electrical switch (ES) state changes from an OFF state to an ON state.
In an embodiment, the first and second voltage regulators (Z1, Z2), the AC-to-DC supply module, the sensing module, and the relay switch are connected via a common ground (GND).
The AC-to-DC supply module includes a first indicator circuit to indicate if DC supply is in accordance with the predetermined voltage V1, the indicator circuit comprises a resistor R3 and a LED L1 connected in a series configuration.
In an embodiment, a second indicator circuit is configured to indicate the actuation of an inductor coil of the relay switch. The second indicator circuit comprises a resistor R8 and a LED L2 in a series configuration. A flyback diode D3 is connected across the inductor to eliminate any flyback. The flyback may be occurred due to a sudden voltage spike across the inductor coil or a sudden change in current in the inductor coil.
The first and second input terminals (T1, T2), the first and second voltage regulators (Z1, Z2), the AC-to-DC supply module, the sensing module, and the relay switch are fabricated on a single Printed Circuit Board (PCB). The PCB is housed in a receptacle. The receptacle is further configured to fit on a DIN rail.
In an embodiment, the generated detection signal is transmitted to a remote monitoring unit. Based on the received detection signal, the remote monitoring unit provides visual and/or auditory feedback to an operator. Furthermore, the operator can remotely monitor the electrical switch (ES) states through the monitoring unit and accordingly take any necessary actions in case of failure or actuation of the electrical switch (ES).
In an embodiment, an electrical switch (ES) of an AC circuit comprises the apparatus 100, wherein the apparatus 100 is built in the electrical switch (ES) as an integrated unit.
In a preferred embodiment, the values of resistors (R1, R2, R3, R4, R5, R6, R7, R8) and capacitors (C1, C2, C3, C4, C5, C6) are as follows:
• R1 = 100O, R2 = 100O, R3 = 4.7KO, R4 =10KO, R5 = 10KO, R6 = 330KO, R7= 10KO, R8 = 3.3KO; and
• C1 = 0.47µF, C2 = 0.47µF, C3 = 0.01µF, C4 = 100µF/25V, C5= 1µF/50V, C6= 100µF/25V.
The foregoing description of the embodiments has been provided for purposes of illustration and is not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENTS AND ECONOMICAL SIGNIFICANCE
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of an apparatus for detecting a state of an electrical switch, which:
• retrofits with the electrical switch;
• is compact;
• facilitates remote monitoring of the states of the electrical switch;
• fits on a DIN rail;
• retrofits with the electrical switch of any make, type and ampacity; and
• can be built into the electrical switch as an integrated unit.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments 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 embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.
, Claims:WE CLAIM:
1. An apparatus (100) for detecting a state of an electrical switch (ES) in an AC circuit, said apparatus (100) comprising:
? a first input terminal (T1) connected to a first end (A) of the electrical switch (ES);
? a second input terminal (T2) connected to a second end (B) of the electrical switch (ES);
? an AC-to-DC supply module connected to said first input terminal (T1) and configured to receive AC supply from the AC circuit through said first input terminal (T1), said AC-to-DC supply module comprising:
i. a first in-rush current limiting circuit configured to limit an excess inflowing current of the AC supply from said first input terminal (T1);
ii. a first voltage regulator (Z1) connected to said first in-rush current limiting circuit, said first voltage regulator configured to regulate voltage of the AC supply to develop a constant voltage; and
iii. a first rectifying circuit configured to receive the developed voltage from said first voltage regulator, and is further configured to generate a DC supply of a predetermined voltage V1;
? a sensing unit connected to said second input terminal (T2), said sensing unit configured to receive a potential signal from said second end (B) of the electrical switch (ES) via said second input terminal (T2), said sensing unit comprising:
i. a second in-rush current limiting circuit configured to limit an excess inflowing current of the sensed potential signal;
ii. a second voltage regulator (Z2) connected to said second in-rush current limiting circuit, said a second voltage regulator configured to regulate the sensed potential signal;
iii. a second rectifying circuit configured to receive the regulated potential signal from said second voltage regulator, and further configured to generate a DC signal of a predetermined voltage V2;
iv. a ripple filtering circuit connected to said second rectifying circuit and configured to remove ripples from said generated DC signal; and
v. a Schmitt triggering circuit connected to said ripple filtering circuit and configured to generate a triggering signal, and
? a relay switch (RLY) coupled to said AC-to-DC supply module and said sensing module, said relay switch (RLY) configured to receive DC supply from said AC-to-DC module and the triggering signal from said sensing module,
wherein said relay switch (RLY) is configured to actuate based on the received triggering signal, and further configured to generate a detection signal indicating the state of the electrical switch (ES).
2. The apparatus (100) as claimed in claim 1, wherein the relay switch (RLY) is a normally open switch or a normally closed switch.
3. The apparatus (100) claimed in claim 1, wherein the generated triggering signal is high when the electrical switch (ES) state changes from an ON state to an OFF state.
4. The apparatus (100) claimed in claim 1, wherein the generated triggering signal is high when the electrical switch (ES) state changes from an OFF state to an ON state.
5. The apparatus (100) as claimed in claim 1, wherein said first in-rush current limiting circuit consists of a resistor (R1) and two parallel capacitors (C1, C2), in a series configuration.
6. The apparatus (100) as claimed in claim 1, wherein said second in-rush current limiting circuit consists of a resistor (R2) and a capacitor (C3), in a series configuration.
7. The apparatus (100) as claimed in claim 1, wherein said first and second voltage regulators are Zener diodes (Z1, Z2).
8. The apparatus (100) as claimed in claim 1, wherein the first rectifying circuit comprises:
? a diode (D1) in a forward-biased configuration, said diode (D1) configured to allow positive constant voltage developed across said first voltage regulator (Z1); and
? a first filtering capacitor (C4) configured to receive positive voltage from said diode (D1), and to generate the DC supply of the predetermined voltage (V1).
9. The apparatus (100) as claimed in claim 1, wherein the second rectifying circuit comprises:
? a diode (D2) in a forward-biased configuration, said diode (D2) configured to allow positive voltage of the regulated potential signal; and
? a second filtering capacitor (C5) configured to receive positive voltage from said diode (D2), and to generate the DC signal of the predetermined voltage (V2).
10. The apparatus (100) as claimed in claim 10, wherein said second filtering capacitor (C5) has a capacitance of 1µF.
11. The apparatus (100) as claimed in claim 1, wherein the ripple circuit comprises:
? resistors (R4, R5) connected to said second rectifying circuit; and
? a capacitor (C6) connected between the resistor (R4, R5) terminals.
12. The apparatus (100) as claimed in claim 1, wherein the Schmitt trigger circuit is coupled with said AC-to-DC supply module through a resistor (R7) and said ripple circuit, said Schmitt trigger circuit comprises:
? a first transistor (Q1);
? a second transistor (Q2); and
? a feedback resistor (R6),
wherein the ripple circuit is connected to the base of the first transistor (Q1), an emitter of said first transistor (Q1) and one terminal of said resistor (R7) is connected to the base of the second transistor (Q2), and a feedback loop is formed between the base of the first transistor (Q1) and a collector of said second transistor (Q2) via said feedback resistor (R6).
13. The apparatus (100) as claimed in claim 1, wherein said first and second voltage regulators (Z1, Z2), said AC-to-DC supply module, said sensing module, and said relay switch (RLY) are connected via a common ground (GND).
14. The apparatus (100) as claimed in claim 1, wherein said AC-to-DC supply module includes an indicator circuit to indicate if DC supply is in accordance with the predetermined voltage (V1), said indicator circuit comprises a resistor (R3) and a LED (L1) connected in a series configuration.
15. The apparatus (100) as claimed in claim 1, wherein said first and second input terminals (T1, T2), said first and second voltage regulators, the AC-to-DC supply module, the sensing module, and the relay switch are fabricated on a single Printed Circuit Board (PCB).
16. The apparatus (100) as claimed in claim 16, wherein said fabricated Printed Circuit Board (PCB) is housed in a receptacle.
17. The apparatus (100) as claimed in claim 17, wherein said receptacle is configured to fit on a DIN rail.
18. The apparatus (100) as claimed in claim 1, retrofits with the electrical switch (ES) of the AC circuit.
19. An electrical switch (ES) of an AC circuit comprises an apparatus (100) as claimed in any one of the preceding claims 1-18.

Dated this 01st day of June, 2022

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K.DEWAN & CO.
Authorized Agent of Applicant

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI