DESC:TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to low voltage switching devices. More particularly, the present invention provides a system for voltage sampling/taping in the circuit breakers.

BACKGROUND AND THE PRIOR ART

A circuit breaker is a switch that automatically interrupts flow of electrical current when the rated current is exceeded due to an electrical overload or fault. Typically, a circuit breaker comprises housing, contacts enclosed within the housing, an operating mechanism to operate the contacts, and an arc chute. The operating mechanism of a circuit breaker primarily consists of two springs, a main spring (or a closing spring) and an opening spring (or a return spring). The main spring is used for closing operation, wherein the spring is held in a charged condition by a closing latch. On releasing the closing latch, the spring releases energy, and this turns ON the circuit breaker. The closing spring generates required driving force to close the circuit breaker and charge the opening spring, and energy needed for the vital opening operation is stored in the opening spring when the circuit breaker is in closed position.

With the increase in demand for electricity and the diversification of electrical equipment, electrical equipment protection functions are maturing. The supply voltage is abnormal, if not timely recovery or cut off, when the duration is longer; often will cause damage to electrical equipment, severe and even endanger personal safety. In order to solve the problems caused by abnormal voltage, low-voltage molded case circuit breaker can be through the use of over-voltage and low-voltage protection module or device to detect the abnormal voltage, the voltage of the main circuit, compared with a predetermined value that is too high or too low plastic shell breaker breaking achieve lower line load and equipment protection purposes.
Existing over-voltage protection module products, usually need access to N-phase, mainly for the four-pole circuit breakers, for the three-pole circuit breaker is often not applicable to a certain extent limit • Over voltage protection module on the MCCB range of applications. Over-voltage protection of existing products in the main circuit voltage detection • signal, some taken from the circuit breaker on the line side, when a long time in the case of over-voltage can cause low • voltage protection module part of the electronic circuit damage, when the molded case circuit breaker failure caused the body off phase, these products cannot detect the fault.

Some main circuit voltage detection signal from the load side of the circuit breaker, the circuit breaker due to some fault of the rear, Over voltage protection module electronic circuit will lose power and stop working, and thus cannot indicate that low overvoltage action or actions, and over-current protection fault cannot distinguish between the action, investigation and analysis of system failure would cause some difficulty. A power measurement on a power switch, for example for a power-consuming analysis is required, voltage tap. So far an external device outside the circuit breaker has been employed for this purpose. In order to carry out the energy measurement in the switch itself, but also an internal voltage tap the switch is necessary. If voltage tap is integrated in the circuit breaker itself may be omitted so that an external module. The tap of such a high voltage as it is applied to a primary conductor of a circuit breaker requires a reduction of the voltage by means of voltage dividers to a level acceptable for the measuring electronics. To carry the high voltage signal via interconnects, cables, adapters, and contacts can pollution, high temperatures, leading to possible leakage paths and disturbing influence of electronics by electrical or electromagnetic effects. One difficulty in these circumstances is to create sufficient space for the necessary additional elements in switch housing and to ensure a reliable contact to the primary conductor.

CN202696109 U: disclosed an over-voltage and low-voltage protection device which comprises a power supply circuit, a voltage sampling circuit, a microprocessor circuit, a fault inquiry circuit and an output circuit, wherein the power supply circuit and the voltage sampling circuit take electricity on a load side of a major loop disconnector; the power supply circuit is connected with the voltage sampling circuit, the microprocessor circuit, the fault inquiry circuit and the output circuit to supply power; and the voltage sampling circuit is connected with the microprocessor circuit which is connected with the fault inquiry circuit and the output circuit connected to the major loop disconnector. The over-voltage and low-voltage protection device has the advantages of being capable of avoiding a breakdown of an electronic circuit due to a long-time overvoltage and detecting broken equality caused by a breakdown of a disconnector body, suitable for a tripolar disconnectors and a quadrupole disconnectors, flexible and convenient, convenient to mount, capable of expanding functions of a disconnector in the form of an accessory, and free from changing the structure of the disconnector body; meanwhile, after the disconnector is disconnected due to over-voltage protection or low-voltage protection, the device can provide an outage fault inquiry function and brings convenience to troubleshooting of a power utilization system. In the above cited document provides a voltage sampling for MCCB but may not provide the voltage tapping method.

EP2590199 disclosed a power switch has a switch housing comprising a contact for tapping off a voltage to a primary conductor. A leaf spring is biased against the surface of the primary conductor. A voltage divider is arranged on circuit board, for reducing the picked-up voltage of the primary conductor. The voltage divider is connected with spring element via a conductor track. The above cited prior art document provides voltage sampling for MCCB, arrangement for the voltage tapping which is different from present invention.

Voltage sensing contacts are generally not reliable and sometimes they lose the contacts if they are incorporated in the circuit breaker due to improper design, and may not give the accurate values because of more voltage drop at the contact junction. Contact with the continuously applied spring force is reliable, so it may require more space in the breakers having in market trend of compactness. So the improved design requirement arises for voltage sampling in the compact circuit breakers

Therefore, present invention overcome the disadvantages prevailing in the conventional art and prior arts, and provides a system for providing over-voltage protection to circuit breaker, so that abnormal conditions can be easily prevented and the downstream equipments can also be prevented from damages.

OBJECTS OF THE INVENTION

A basic object of the present invention is to overcome the disadvantages/ drawbacks of the known art.

Another object of the present invention is to provide a system for voltage sampling using a leaf spring contact for providing over-voltage protection to circuit breaker.

Another object of the present invention is to provide a system for over-voltage protection by an ease to the user in changing termination type for switching devices.

These and other advantages of the present invention will become readily apparent from the following detailed description read in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

In an aspect of the present invention, there is provided a system of voltage sampling for providing over-voltage protection to a circuit breaker, said system comprising:
a voltage module; a leaf spring contact; said leaf spring contact operatively connected to said voltage module and said voltage module operatively connected to a release assembly;
a microprocessor release operatively connected to said leaf spring contact;
a current transformer operatively connected in said release assembly;
wherein in said system, said leaf spring contact facilitate voltage tapping from said release assembly and said voltage module facilitate voltage tapping to an electronic processing unit and therefore providing an input to said microprocessor release for tripping said circuit breaker by generating a signal according to fault condition for protecting said circuit breaker from overload condition.

In another aspect of the present invention, a system of voltage sampling for providing over-voltage protection to a circuit breaker is disclosed. The system comprises of a voltage sampling circuit comprising a voltage module configured to tape a ground voltage from an electronic processing unit; a leaf spring contact with at least two ends; wherein one end of the leaf spring contact is communicably coupled with the voltage module and the other end of the leaf spring contact is communicably coupled with the microprocessor card; and the leaf spring contact is configured for tapping a voltage form a release assembly of the circuit breaker; and the electronic processing unit is configured to: receive the voltage form the release assembly in the form of a value and the ground voltage in the form of a value; compare the input voltages with one or more pre-defined values of voltage to detect change in values; and thereby issue, if change in values detected, a trip signal to breaker and provide over-voltage protection.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The following drawings are illustrative of particular examples for enabling methods of the present invention, are descriptive of some of the methods, and are not intended to limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description.

Figure 1 illustrates the voltage module PCB with the leaf spring contact and output wires

Figure 2 illustrates the voltage module PCB assembly with the insulating shield

Figure 3 illustrates the voltage module PCB assembly with the insulating shield, when Leaf spring contact in free position.

Figure 4 illustrates the exploded view (sectioned) of microprocessor release.

Figure 5 illustrates the exploded view (sectioned) of microprocessor release with voltage PCB assembled in housing.

Figure 6 illustrates the exploded view (sectioned) of microprocessor release –sensor being is assembled in the release housing.

Figure 7 illustrates the section view of complete microprocessor release assembly.

Figure 8 illustrates the section view when leaf spring contact in compressed position.

Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.

Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

Accordingly, present invention provides the reliable contact for voltage sampling in a compact space. It is also easy to assemble with the simple arrangement. Leaf spring contacts can be located at any location in the breaker for voltage tap. Material of the leaf spring can be any metal suitable to design. Plating on a leaf spring can be either gold or silver. Assembly sequence of the components explained above can be different from shown.

The invention provide an easy to install, easy to troubleshoot power system failure, and three, four-pole molded case circuit breakers can be applied over-voltage protection devices.

The present invention relates to the over-voltage protection devices, the power supply circuit and the voltage sampling circuit breaker load side to take power in the rear of the circuit breaker due to over-voltage protection, over voltage protection device off, thereby to avoid over-voltage electronic circuit protection device inside prolonged overvoltage damage, and can detect failure of the circuit breaker body due to the same problem of breaking. Over voltage protection device to take a three-phase line voltage is not connected to N-phase, both for three-pole circuit breaker, can also be used for four-pole circuit breakers, flexible and easy to expand the circuit breaker attachment functionality, simple installation, without changing the circuit The main body structure, while in the low-voltage protection • overvoltage or leaving the circuit breaker off, power failure to provide query capabilities to facilitate troubleshooting electrical system failure.

Voltage sampling circuit is comprised of a silver/gold plated or non plated leaf spring contact for tapping a voltage form the release side of the circuit breaker and Voltage module tapes ground from electronic processing unit and sends o/p to the same for further process such as deriving voltage level, communication with customer. Leaf spring contacts which are the parts of microprocessor release can be connected to the terminal (current carrying path) at any points in the release. They continuously apply spring force on the contact due to spring force of the leaf spring. Leaf spring contacts are generally plated by gold/silver material to reduce the voltage drop at the contacts, which will voltage measurements close to the accurate values. Leaf spring contacts are also compact in the size and can be accommodated in the compact breaker easily without creating a space crunch. One end of the leaf springs are soldered to the voltage module circuit and o/p of this circuit will provide signal to the microprocessor card. Differential values are being compared to the ref values and microprocessor release generates the signal according to the type of the fault. So the abnormal conditions can be easily prevented and the downstream equipments can also be prevented from damages.

Referring to the figure 1 voltage module (2) card has been shown with the leaf spring contact (3) and o/p cables (1). Leaf spring (3) and o/p cables (1) are soldered on the voltage module (2) circuit board (voltage divider). Leaf spring is either gold or silver plated for reducing the voltage drop at the contact and accurate measurement.

Voltage module with the insulating cover (4) is shown in the figure 2. Insulating shield (4) insulate the voltage module (2) circuit board from the current carrying conductor (11) and the leaf spring (3). It ensures the only one joint (5) between the leaf spring (3) and voltage module (2) circuit board is the soldered one, which allows more insulated space on board to place the components/resistors and reduces the size of the circuit board.

Figure 3 shows the voltage module (2) assembly in the sectioned view. Here the leaf spring (3) in no load condition and leaf spring joint with the circuit board are indicated. Fig also depicts that insulating shield (4) is a barrier between live conductor and the circuit board.

Figure 4 shows the exploded view (sectioned) of a release assembly (8). Microprocessor circuit (9) board, Current Transformer (sensor), voltage module assembly, Release housing, closing cover (6) and front cover (10) are the different modules of the microprocessor release. Current transformer and voltage module (2) which measure the current and voltage respectively gives input to microprocessor release. In differential conditions microprocessor release generates the command to trip the breaker by means of FSD.

In figure 5, voltage module is assembled in the release housing through the sliding ribs. Sliding ribs ensure the fixed position of the voltage module in the release housing.

Referring to figure 6, it shows the current transformer getting assembly in the release housing. In the position of the current transformer shown in the figure .leaf spring is in no load –free position.

Figure 7 shows the complete assembly of the microprocessor release in a sectioned view. Different modules of the microprocessor release are mentioned in the figure. In this assembled position leaf spring contact is in a forced position and it will always exert force in the direction of the current carrying conductor, so the contact between the current carrying conductor and the leaf spring will be reliable. Detail view of area highlighted in figure is shown in figure 8.

Figure 8 represents the enlarged view of the marked section shown in figure 7. In enlarged view, it is clearly seen that leaf spring contact and current carrying conductor form a strong electrical joint due to the spring force excreted by the leaf spring.

In one implementnantion, a system of voltage sampling for providing over-voltage protection to a circuit breaker is disclosed. The system comprises of a voltage sampling circuit comprising a voltage module configured to tape a ground voltage from an electronic processing unit; a leaf spring contact with at least two ends; wherein one end of the leaf spring contact is communicably coupled with the voltage module and the other end of the leaf spring contact is communicably coupled with the microprocessor card; and the leaf spring contact is configured for tapping a voltage form a release assembly of the circuit breaker; and the electronic processing unit is configured to: receive the voltage form the release assembly in the form of a value and the ground voltage in the form of a value; compare the input voltages with one or more pre-defined values of voltage to detect change in values; and thereby issue, if change in values detected, a trip signal to breaker and provide over-voltage protection.

In one implementnantion, in the system, leaf spring contacts facilitate the voltage tapping from the respective conductors to voltage divider circuits/modules. Divider circuits will provide the signal to the electronic processing unit, which will eventually provide the tripping signal to the circuit breaker in any abnormal conditions to protect the entire electrical circuitry.

In one implementnantion, the leaf spring contacts are plated by a specific material selected from at least one of gold or silver.

In one implementnantion, the electronic processing unit comprises a microprocessor release configured to generate the trip signal if change in values detected.

In one implementnantion, the leaf spring contacts are plated using a material for reducing voltage drop at said contact.

In one implementnantion, the voltage module is assembled on a sliding rib of housing/release box for maintaining a fixed position of the voltage module in said release assembly.
In one implementnantion, the voltage module is insulated using an insulating shield from a current carrying conductor and said leaf spring contact for volume optimization of the voltage divider circuit.

In one implementnantion, the one of the novel features of the invention is that, it provides the reliable contact for voltage sampling in a compact space. It is also easy to assemble with the simple arrangement. Leaf spring contacts can be located at any location in the breaker for voltage tap. Material of the leaf spring can be any metal suitable to design. Plating on a leaf spring can be either gold or silver. Assembly sequence of the components explained above can be different from shown.

Although a system of voltage sampling for providing over-voltage protection to a circuit breaker is been described in language specific to structural features and/or methods, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or methods or devices described. Rather, the specific features are disclosed as examples of implementations of a system of voltage sampling for providing over-voltage protection to a circuit breaker.
,CLAIMS:1. A system of voltage sampling for providing over-voltage protection to a circuit breaker, said system comprising:
a voltage sampling circuit comprising a voltage module configured to tape a ground voltage from an electronic processing unit;
a leaf spring contact with at least two ends; wherein
one end of the leaf spring contact is communicably coupled with the voltage module and the other end of the leaf spring contact is communicably coupled with the microprocessor card; and
the leaf spring contact is configured for tapping a voltage form a release assembly of the circuit breaker; and
the electronic processing unit is configured to:
receive the voltage form the release assembly in the form of a value and the ground voltage in the form of a value;
compare the input voltages with one or more pre- defined values of voltage to detect change in values; and thereby
issue, if change in values detected, a trip signal to breaker and provide over-voltage protection.

2. The system as claimed in claim 1, wherein the leaf spring contacts are plated by a specific material selected from at least one of gold or silver.

3. The system as claimed in any one of the preceding claims, wherein the electronic processing unit comprises a microprocessor release configured to generate the trip signal if change in values detected.

4. The system as claimed in any one of the preceding claims, wherein the leaf spring contact are plated using a material for reducing voltage drop at said contact.

5. The system as claimed in any one of the preceding claims, wherein the voltage module is assembled on a sliding rib of housing for maintaining a fixed position of the voltage module in said release assembly.

6. The system as claimed in any one of the preceding claims, wherein the voltage module is insulated using a insulating shield from a current carrying conductor and said leaf spring contact for volume optimization of the voltage divider circuit.

7. The system as claimed in any one of the preceding claims, wherein said leaf spring contact connected to a current carrying terminal for continuously providing spring force on a contact of said circuit breaker.