Claims:1. A system comprising:
a monitoring device (102) having an internal switching mechanism to make or break a control circuit;
an automatic power factor controller (APFC) relay (104) operatively coupled with said monitoring device (102) in series with contactor coil (A1 and A2), wherein in manual mode, said contactor coil is energized through said APFC relay, along with said monitoring device (102) being activated so as to measure voltage across capacitors of respective branch; and
an incomer interlock (200) comprising an actuator that is operatively coupled with said monitoring device (102) such that when said monitoring device measures the voltage across the capacitors, handle of the incomer interlock (200) is locked so as to prevent a user from switching ON main incomer till the capacitors are discharged below safe value.

2. The system of claim 1, wherein, in manual mode, post activation of the monitoring device (102), said monitoring device disconnects its internal switches and is operated based on voltage across said capacitors.

3. The system of claim 1, wherein said monitoring device measures the voltage across the capacitors when the main incomer is switched OFF.

4. The system of claim 1, wherein said monitoring device measures the voltage across the capacitors at terminals (S1 and S2).

5. The system of claim 1, wherein after the capacitors are discharged below the safe value, the handle of the incomer interlock (200) is unlocked so as to enable the user to switch ON the main incomer.

6. The system of claim 1, wherein, in automatic operation, monitoring device is reset but incomer interlock (200) is locked till the capacitors are discharged.
, Description:TECHNICAL FIELD
[0001] The present disclosure relates to Automatic Power Factor Control Panels (APFC), and more specifically relates to, safety switching interlock for automatic power factor correction (APFC) panels used for power factor corrections.

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, contactor is used for capacitor switching. The contactor can be operated in either auto mode or manual mode through relay. If the panel is operating in auto mode, the switching time of the capacitor is controlled by the relay. Whereas, in case of manual operation the switching time need to be monitored. If the capacitor is switched ON again before it is fully discharged, it may result in capacitor failure. In addition, if operating personnel access it before complete discharge, it may result in to a fatal accident. Hence, there is a need to provide interlocks to ensure the safe operation of panel in both auto as well as manual mode.
[0004] Automatic Power Factor Control (APFC) panels are mainly used for the improvement of Power Factor. Power Factor can be explained as ratio of active power to apparent power and it is a key factor in measuring electrical consumption. Everyone knows that how costly electricity has become in present time. Therefore it becomes utmost important to cut down on electrical consumption for reducing expenditure. APFC Panels come real handy in the achievement of this purpose Use of these control panels becomes indispensable in those industries where electrical installations are meant to supply to large electrical load. A dip in Power Factor can attract operational losses and a penalty from electricity board, responsible for electricity supply. APFC Panels can effectively and automatically manage quickly changing and scattered loads along with the retention of high Power Factor. We are renowned manufacturers of APFC Panels symbolized with quality and reliability. These are available in different current ratings to cater to distinct applications.
[0005] However, the current products in the market do not have electrical or mechanical interlocks. The capacitor is accessible in the operating condition, increasing risk of safety
[0006] Whereas there is certainly nothing wrong with existing products in the market, nonetheless, there still exists a need to provide an efficient, effective, reliable, and improved compensation mechanism for building expansion. Further, there is a need of means for compensating the difference between the thermal elongations of dissimilar materials used in busways. Furthermore, there is a need of a busbar expansion unit or busbar expansion joint for ingress protection.
[0007] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0008] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about”. Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0009] 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.
[00010] 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.
[00011] 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.

SUMMARY
[00012] The present disclosure relates to Automatic Power Factor Control Panels (APFC), and more specifically relates to, safety switching interlock for automatic power factor correction (APFC) panels used for power factor corrections.
[00013] Embodiments of the present disclosure relates to safety features in APFC panels used for power factor corrections in Industrial as well as commercial segment. It follows that the capacitors used in APFC panel should fully discharge before it is switched ON again. This helps to maintain life of capacitor. In addition, the possibility of electrical shock or capacitor failure reduces. The present invention ensures access to panel only after the capacitor is fully discharged.
[00014] In an exemplary embodiment, the present invention offers safety features by providing electrical and mechanical safety interlocks. The concept ensures safety feature irrespective of the operating mode of panel. The electrical interlock safeguards the switching of capacitors while the panel is operating in manual mode. In addition, the mechanical interlock ensures that the assembly inside the panel is not accessible until the capacitors are discharged.
[00015] The primary objective of the present invention is to ensure safe operation of automatic power factor controller panels. This also ensures safety of the personnel operating the panel manually. There is a possibility of capacitor getting damaged in case the charged capacitors are switched ON again before it getting fully discharged. This affects output efficiency and reduces life of capacitors.
[00016] Accordingly, an aspect of the present disclosure provides a system having a monitoring device, an automatic power factor controller (APFC) relay, and an incomer interlock. The monitoring device can include an internal switching mechanism to make or break a control circuit. The APFC relay can be operatively coupled with said monitoring device in series with contactor coil (A1 and A2), such that in manual mode, said contactor coil is energized through said APFC relay, along with said monitoring device being activated so as to measure voltage across capacitors of respective branch.
[00017] In an aspect, the incomer interlock includes an actuator that is operatively coupled with said monitoring device such that when said monitoring device measures the voltage across the capacitors, handle of the incomer interlock is locked so as to prevent a user from switching ON main incomer till the capacitors are discharged below safe value.
[00018] In an aspect, in manual mode, post activation of the monitoring device, said monitoring device disconnects its internal switches and is operated based on voltage across said capacitors.
[00019] In an aspect, said monitoring device measures the voltage across the capacitors when the main incomer is switched OFF.
[00020] In an aspect, said monitoring device measures the voltage across the capacitors at terminals (S1 and S2).
[00021] In an aspect, after the capacitors are discharged below the safe value, the handle of the incomer interlock is unlocked so as to enable the user to switch ON the main incomer.
[00022] In an aspect, in automatic operation, monitoring device is reset but incomer interlock is locked till the capacitors are discharged.
[00023] In contrast to the conventional panels, the present disclosure provides safety features in APFC panels used for power factor corrections in Industrial as well as commercial segment. It follows that the capacitors used in APFC panel should fully discharge before it is switched ON again. This helps to maintain life of capacitor. In addition, the possibility of electrical shock or capacitor failure reduces. The present invention ensures access to panel only after the capacitor is fully discharged.
[00024] In an exemplary embodiment, the present invention offers safety features by providing electrical and mechanical safety interlocks. The concept ensures safety feature irrespective of the operating mode of panel. The electrical interlock safeguards the switching of capacitors while the panel is operating in manual mode. In addition, the mechanical interlock ensures that the assembly inside the panel is not accessible until the capacitors are discharged.
[00025] The present invention ensures safe operation of automatic power factor controller panels. This also ensures safety of the personnel operating the panel manually. There is a possibility of capacitor getting damaged in case the charged capacitors are switched ON again before it getting fully discharged. This affects output efficiency and reduces life of capacitors.
[00026] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[00027] 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, and wherein:
[00028] FIG. 1 illustrates a monitoring device X with internal switching facility to make or break the control circuit connected with the APFC relay in series with the contactor coil A1 and A2, in accordance with an exemplary embodiment of the present disclosure.
[00029] FIG. 2 illustrates an incomer interlock Z, in accordance with another exemplary embodiment of the present disclosure.
[00030] FIG. 3 illustrates a door interlock D1, in accordance with another exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION
[00031] 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.
[00032] 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.
[00033] 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.
[00034] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. These exemplary embodiments are provided only for illustrative purposes and so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those of ordinary skill in the art. The invention disclosed may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Various modifications will be readily apparent to persons skilled in the art. The general principles defined herein may be applied to other embodiments and applications without departing from the scope of the invention. Moreover, all statements herein reciting embodiments of the invention, 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). Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention.
[00035] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[00036] 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.
[00037] 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.
[00038] The present disclosure relates to Automatic Power Factor Control Panels (APFC), and more specifically relates to, safety switching interlock for automatic power factor correction (APFC) panels used for power factor corrections.
[00039] Embodiments of the present disclosure relates to safety features in APFC panels used for power factor corrections in Industrial as well as commercial segment. It follows that the capacitors used in APFC panel should fully discharge before it is switched ON again. This helps to maintain life of capacitor. In addition, the possibility of electrical shock or capacitor failure reduces. The present invention ensures access to panel only after the capacitor is fully discharged.
[00040] In an exemplary embodiment, the present invention offers safety features by providing electrical and mechanical safety interlocks. The concept ensures safety feature irrespective of the operating mode of panel. The electrical interlock safeguards the switching of capacitors while the panel is operating in manual mode. In addition, the mechanical interlock ensures that the assembly inside the panel is not accessible until the capacitors are discharged.
[00041] The primary objective of the present invention is to ensure safe operation of automatic power factor controller panels. This also ensures safety of the personnel operating the panel manually. There is a possibility of capacitor getting damaged in case the charged capacitors are switched ON again before it getting fully discharged. This affects output efficiency and reduces life of capacitors.
[00042] Accordingly, an aspect of the present disclosure provides a system having a monitoring device, an automatic power factor controller (APFC) relay, and an incomer interlock. The monitoring device can include an internal switching mechanism to make or break a control circuit. The APFC relay can be operatively coupled with said monitoring device in series with contactor coil (A1 and A2), such that in manual mode, said contactor coil is energized through said APFC relay, along with said monitoring device being activated so as to measure voltage across capacitors of respective branch.
[00043] In an aspect, the incomer interlock includes an actuator that is operatively coupled with said monitoring device such that when said monitoring device measures the voltage across the capacitors, handle of the incomer interlock is locked so as to prevent a user from switching ON main incomer till the capacitors are discharged below safe value.
[00044] In an aspect, in manual mode, post activation of the monitoring device, said monitoring device disconnects its internal switches and is operated based on voltage across said capacitors.
[00045] In an aspect, said monitoring device measures the voltage across the capacitors when the main incomer is switched OFF.
[00046] In an aspect, said monitoring device measures the voltage across the capacitors at terminals (S1 and S2).
[00047] In an aspect, after the capacitors are discharged below the safe value, the handle of the incomer interlock is unlocked so as to enable the user to switch ON the main incomer.
[00048] In an aspect, in automatic operation, monitoring device is reset but incomer interlock is locked till the capacitors are discharged.
[00049] In contrast to the conventional panels, the present disclosure provides safety features in APFC panels used for power factor corrections in Industrial as well as commercial segment. It follows that the capacitors used in APFC panel should fully discharge before it is switched ON again. This helps to maintain life of capacitor. In addition, the possibility of electrical shock or capacitor failure reduces. The present invention ensures access to panel only after the capacitor is fully discharged.
[00050] In an exemplary embodiment, the present invention offers safety features by providing electrical and mechanical safety interlocks. The concept ensures safety feature irrespective of the operating mode of panel. The electrical interlock safeguards the switching of capacitors while the panel is operating in manual mode. In addition, the mechanical interlock ensures that the assembly inside the panel is not accessible until the capacitors are discharged.
[00051] The present invention ensures safe operation of automatic power factor controller panels. This also ensures safety of the personnel operating the panel manually. There is a possibility of capacitor getting damaged in case the charged capacitors are switched ON again before it getting fully discharged. This affects output efficiency and reduces life of capacitors
[00052] The panel configuration of automatic power factor controller comprises of main incomer and of multiple steps depending on the compensation required in the electrical system. The main incomer controls the multiple steps comprising components like APFC relay, contactors, fuses, and capacitors. The relay with options of operating in automatic as well as manual mode operates the contactors. The contactors in turn switches the capacitors connected in series with the contactors. Fuses are connected in series with the contactors to provide short circuit protection. These series assembly of these components forms one step of particular rating.
[00053] When APFC relay is operated in automatic mode, due to the inherent feature of time delay to operate steps, the switching of capacitor is done only after it is discharged below safe voltage level. However, this safe operation cannot be ensured when operating the panel in manual mode. To incorporate this feature during manual operation of panel and overcome the above issue a new design was required. The capacitor discharge below safe voltage level cannot be assured by providing only time delay independent of capacitor voltage. Hence, the interlock dependent on capacitor voltage was designed which assures proper functioning of the control circuit or interlock designed. To confirm the personnel safety while working on the panel, the interlock helps locking the door and allowing access to the assembly components releasing the locked door only after the capacitors are fully discharged.
[00054] In the present innovation, additional components for monitoring the voltage across capacitors and controlling the operation of switching device are added in the circuit that ensures the safe operation of panel. The monitoring device will measure the voltage across the capacitors in the following condition, i.e., when panel is operated in manual mode by means of APFC relay, and while switching ON/OFF main incomer.
[00055] In both these conditions until the capacitors are fully discharged, the user will not be able to energize the panel as well as the main incomer. After it is completely discharged, the panel can be loaded again and the capacitors can be connected in the circuit
[00056] The main purpose of the present invention is to provide safe operating environment of panel. Since, the requirement of this sort of product is in commercial as well as industrial segment. Safe operation of panel ensuring safety of personnel operating it is of prime importance.
[00057] The concept basically involves three main functions / parts as explained below:
[00058] As shown in FIG. 1, a monitoring device X with internal switching facility to make or break the control circuit is connected with the APFC relay in series with the contactor coil A1 and A2. While operating the panel in manual mode the contactor coil is energized through APFC relay. At the same time, the device X that measures the voltage across capacitors of the respected branch will be activated. The device can disconnect all the internal switches and can be operated based on the voltage across capacitors.
[00059] As shown in FIG. 2, an incomer interlock Z consists of an actuator embedded with electronic circuit that is connected with monitoring device X. As soon as the main incomer (Z) is switched off, the monitoring device will measure the voltage across capacitors (at terminals S1 and S2) and will lock the handle of the incomer. This will prevent the user to switch on the main incomer till the capacitors are discharged below safe value before energizing it for the second time. After the capacitor is discharged below the safe value, the incomer handle gets unlocked by actuator and allows user to switch ON the incomer again.
[00060] As shown in FIG. 3, D1 is the door interlock. As soon as actuator connected to incomer unlocks the handle, it operates another actuator D1 connected to the door which doesn’t allow user to open the door until the capacitor gets discharged fully.
[00061] In case of automatic operation of the panel, the device X will get reset, since the time delay will be observed by the APFC relay itself. But, the actuator D1 will be activated to prevent opening of door till the capacitors are discharged to a safer value.
[00062] It may be appreciated that, the most important feature of this invention is targeting safety of personnel operating the panel or the assembly of components. Since, it will be used for commercial segment; the safety is of prime importance. The invention offers higher level of safety feature taking in to consideration all the mal-function that can occur while the panel is in operating condition. Hence an advance level of interlocking is being conceptualized that takes in to consideration the mechanical as well as electrical components.
[00063] Thus, in contrast to the conventional panels, the proposed panels according to the present disclosure which permits the interlocking both in manual as well as in auto operating mode of panel, as well as, it provides advance level of interlocking involving electronic devices along with mechanical components and added with the control circuit of the panel.
[00064] It may be also appreciated that, the interlocking can be of two types an electrical interlock and a mechanical interlock. The electrical interlock is a device or assembly of components which is programmed to monitor the fluctuations in the defined electrical parameter and governs the operation of other devices. The mechanical interlock is a component or assembly of components which is linked with the electrical interlock. It is operated once the command from the electrical interlock is received.
[00065] 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. 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 scope of the appended claims.
[00066] 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 scope of the disclosure, as described in the claims.
[00067] In the description of the present specification, reference to the term "one embodiment," "an embodiments", "an example", "an instance", or "some examples" and the description is meant in connection with the embodiment or example described The particular feature, structure, material, or characteristic included in the present invention, at least one embodiment or example. In the present specification, the term of the above schematic representation is not necessarily for the same embodiment or example. Furthermore, the particular features structures, materials, or characteristics described in any one or more embodiments or examples in proper manner. Moreover, those skilled in the art can be described in the specification of different embodiments or examples are joined and combinations thereof.
[00068] All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.
[00069] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
[00070] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
[00071] 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
[00072] The present disclosure permits the interlocking both in manual as well as in auto operating mode of panel.
[00073] The present disclosure provides an advance level of interlocking involving electronic devices along with mechanical components and added with the control circuit of the panel.