DESC:FIELD OF INVENTION

The present invention relates to a real-time monitoring system. In particular, the present invention relates to a real-time neutral earth monitoring system for any equipment. More particularly, the present invention relates to a method for monitoring neutral earth condition in real-time.

BACKGROUND OF THE INVENTION

Generally, there is routine activity called periodic maintenance to check all the voltages or grounding/earth related issues in almost all the manufacturing industries. Very few voltmeters or apparatus are available in market which display such voltages, voltage fluctuations or grounding related issues. Sometimes, NEV (neutral earth voltage) must be checked during the preventive maintenance activity and if this NEV voltage is more than 1 Volt, often there are chances that some electronic card would fail. Moreover, if grounding is not properly done, there could be electrical noise generation in digital signals. This would lead to malfunctioning of the concerned machine. Sometimes, there is also a possibility of weak grounding or break in grounding/earth, which may lead to serious accidents even to the extent of electrocution of human beings. Some of the prior art documents have offered solutions to address the above issue.

PRIOR ART

US 20160306003 A1 discloses bad ground and reverse polarity detection for HVAC controls. It comprises HVAC control or comparator which is configured to receive a neutral signal at the analog input. It measures the voltage of a neutral signal with respect to earth ground. If the error is present in neutral to earth voltage compared to the first threshold voltage, then the error indicator provides a first indicator status indicative of a bad ground state. Further, if the voltage is above the second threshold voltage, then the error indicator provides a second indicator status of a reverse polarity state.
CA 2818183 C discloses an intelligent electronic device. It provides a restricted earth fault protection to the components of an electrical power delivery system using both an amplitude comparator and a phase angle comparator, which are further configured to independently detect the faults. Further, the amplitude comparator configured to receive the input and to selectively generate an amplitude comparator fault indicator based on the input with respect to an amplitude threshold.

CN 203504134 U discloses a current circuit breaking protection device. It comprises a converter, a current converter, a controller, and a current breaker. The controller comprises a comparator which has two inputs. When the detected voltage is less than the predetermined voltage, it does not output the detection signal further. If the detected voltage is greater than the predetermined voltage, the comparator outputs a trip signal. This trip signal is fetched to the circuit breaker, i.e. the relay.

DISADVANTAGES WITH THE PRIOR ART

The following are the disadvantages with the prior arts discussed above:

None of the abovementioned prior art documents fully solve the disadvantages associated with the real-time monitoring of the neutral earth as discussed above. For example, a system which could avoid or even eliminate electronic card failure in CNC machines.

Therefore, there is an existing need for a system and method for monitoring real-time neutral earth in real-time.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:
An object of the present invention is to provide a system for real-time monitoring of the neutral earth voltage of machineries.

Another object of the present invention is to provide a system for real-time voltage monitoring, which prevents any electrocution of the shop-personnel.

Still another object of the present invention is to provide a system for real-time voltage monitoring which eliminates an electronic card failure in CNC machines.

Yet another object of the present invention is to provide a system for real-time voltage monitoring, which detects and issues alerts about improper grounding.

A further object of the present invention is to provide a system for real-time voltage monitoring, which prevents electrical noise generation in the digital signals, which could cause malfunctioning of the machines.

A further object of the present invention is to provide a method for real-time monitoring of neutral earth voltage of machineries.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a system for real-time monitoring of the neutral earth condition of a machine/component connected thereto by detecting the difference between the neutral earth voltage (NEV) and a configured voltage predefined therefor and to indicate an improper neutral earth condition to the machine operator in order to take a remedial action to prevent any accident.
Typically, the system is configured as a Machine Care Earth Unit (MECU), comprising:

• a step-down transformer;

• a bridge rectifier to convert AC voltage to DC voltage;

• a button for setting the configured voltage;

• a dual 7-segment display (SSD) for displaying the neutral earth voltage (NEV) and the configured voltage respectively; and

• an integrated circuit (IC) having a controller for detecting in real-time, the voltage difference between the neutral earth voltage (NEV) and the voltage configured for the neutral and earth terminals of the machine/component;

wherein the IC is activated whenever the neutral earth voltage (NEV) exceeds the configured voltage.

Typically, the step-down transformer is used to step down the machine/component voltage, preferably from 220V or 230V AC to 5V AC.

Typically, the bridge rectifier is used to convert the AC voltage to DC voltage to be supplied to the controller.

Typically, the IC is configured as an audio and visual alarm about any detected improper neutral earth condition.

Typically, the IC comprises:

• a respective neutral voltage and earthing voltage points connected to a means for comparing in real-time the neutral earth voltage (NEV) with the configured voltage;

• a respective 7-segment display (SSD) for displaying the neutral earth voltage (NEV) and the configured voltage;

• a button connected to the comparing means and a programming means for setting the configured voltage;
• a relay to be switched on by the comparing means,

wherein the IC comprises a Micro/Millimeter-wave Monolithic Integrated Circuit (MIMIC).

Typically, the relay is activated for starting the MIMIC, whenever the neutral earth voltage (NEV) is detected higher than the configured voltage to start the MIMIC.

Typically, the MIMIC is configured to issue an alarm for alerting the machine operator about the presence of an improper neutral earth condition in order to take a remedial action to prevent any accident.

Typically, the alarm is sounded by means of a buzzer or a mixture of audible and visual indication.

In accordance with the present invention, there is also provided a method for real-time monitoring of the neutral earth condition of a machine/component connected thereto using the Machine Care Earth Unit (MECU) system, the method comprises the following method steps:

• connecting 220V/230V power supply and neutral thereof to the Machine Earth Care Unit (MECU) at input power;

• setting a predefined voltage Y configured by means of the programming means;

• stepping down the supply voltage from 220V/230V to 5V AC for supply to the controller;

• converting the AC into DC voltage by means of the rectifier;

• receiving the neutral earth voltage X from the machine and comparing the neutral earth voltage (NEV) X with the configured voltage Y;

• switching on a relay when the neutral earth voltage (NEV) X is detected to be higher than the configured voltage Y;

• starting the operation of said MIMIC for issuing an alarm by means of a buzzer or a mixture of audible and visual alarm about the presence of an improper neutral earth condition;

whereby the machine operator takes a remedial action to prevent any accident, such as electrocution of the personnel present in the vicinity of said machine/component.

DESCRIPTION OF THE INVENTION

The present invention relates to configuring and producing a system for monitoring grounding condition in real-time for making the machines safe in case of poor electrical grounding and thereby for eliminating the failure of sophisticated and often expensive electronic cards of the machines.

Most of the machine maintenance team check the condition of grounding only during the preventive maintenance and this is mostly done offline. Normally, the frequency of such checking this grounding condition is every 3 to 6 months. So, presently there is no system or method available for carrying out the monitoring of the grounding condition in real-time and for receiving the feedbacks thereof.

Whenever, a weak grounding or break in grounding occurs, the sophisticated electronic card components would fail and there is always an imminent risk to cause the electrocution of human being present in the vicinity of the concerned machine/components. In case, the machine grounding/earth is weak or disconnected, there could be a possibility of high voltage difference present between the neutral and grounding. Ideally speaking, neutral earth voltage (NEV) should be below 1 V.

The Machine Earth Care Unit (MECU) configured in accordance with the present invention basically consists of 5 main components, i.e. a 7-segment display, a voltage comparator IC, a relay and electronics component, electronics circuit board and MIMIC or audible/visual siren/alarm.

MECU has two terminals connected between the earth and neutral of the machine. This can be configured digitally between 0.05V and 4.0 V at any-time. The NEV can be easily read in real-time and the voltage can be configured accordingly. When the real-time voltage crosses this configured voltage, the MIMIC starts operating.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings, wherein:

Figure 1 shows a schematic block diagram of system for monitoring of neutral earth condition in real-time and configured according to the present invention.

Figure 2 shows a front view of the MECU of Figure 1.

Figure 3 shows a detailed circuit diagram of the MECU of Figure 1.

Figure 4 shows flow chart of the operation of MECU of Figure 1 while operating the concerned CNC machine.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, the system for monitoring of the neutral earth condition in real-time and configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention in any way.
Figure 1 shows a schematic block diagram of the system for monitoring of the neutral earth condition in real-time and configured in accordance with the present invention. It includes a Machine Care Earth Unit (MECU) 50 connected to the machine 10 requiring the neutral to earth voltage (NEV) thereof to be monitored in real-time. The MCU consists of a neutral phase 11 from the relevant CNC machine 10, a step-down transformer 12 to step down voltage from 220V or 230V AC to 5V AC, an earthing/ground connection 13, a bridge rectifier 14 to convert AC voltage to DC voltage, a neutral to earth voltage point 16, a dual display 24, 26 configured for indicating dynamic NEV voltage X and NEV voltage Y. All these components are connected to the comparator integrated circuit (IC) 20 in the manner depicted herein for the purpose of scanning and comparing the dynamic NEV Voltage X with the configured NEV voltage Y. A programming IC 32 is also provided for displayed dynamic voltage X and configured voltage Y. A push button 19 is provided for setting the NEV voltage Y. The comparator IC 20 is connected further to a MIMIC 30, which represents an audible and visual siren or buzzer alarm. The comparator IC 20 compares the set voltage value Y (settable between 0.5 to 1.0 V and continuously displayed on the first display 24 of MCU with the input neutral to earth voltage (NEV) X, which is displayed on the second display 26. If the value of NEV X is sensed by the comparator IC 20 to be greater than set voltage (i.e. X > Y), it signals the potential-free relay 28 of the MIMIC 30 to be switched on. MIMIC 30 sounds an alarm to alert the machine operator to take necessary remedial action and to look for the presence of weak grounding or break in grounding/earth in order to prevent the failure of sophisticated electronic card components of the machine. This eliminates any imminent risk of the occurrence of electrocution of the machine operator or other persons present in contact with the concerned machine/components. A reset button is also provided, which functions only if the dynamic NEV Voltage X is less than configured voltage Y.

Figure 2 shows a front view of the MECU 50 of Figure 1. It depicts NEV point 11, 13 and a configured voltage 12, both indicated by means of a 3-Digit seven segment display (SSD) each. A voltage configuration button 19 including four (4) NO-PUSH buttons “Enter”, “Up”, “Set” and “Down” is also provided. Here, the voltage is stepped down from 220V AC to 5V AC.

Figure 3 shows a detailed circuit diagram of Machine Earth Care Unit (MECU) 50 of Figure 1. MECU 50 includes a comparator IC 20 receiving input NEV voltages X sensed from points 11, 13. This input voltage X is then compared with the configured voltage Y received from the programing IC 32, which is also connected to a unit consisting of first and second displays 24, 26 and a configuration button 19 for setting the voltage Y for monitoring NEV voltage X. Once, the comparator 20 detects X being greater than set voltage Y, it issues a signal to a relay 28 and MIMIC 30 for raising an alarm to alert the machine operator to take remedial action as already discussed earlier.

Figure 4 shows a flow chart of the operation of the MECU 50 for operating a CNC machine 10. On switching on power at step 100, configuration voltage Y at step 200 is compared with the scanned NEV voltage X at step 300 and if it is detected at subsequent process step 400 that X > Y, the buzzer and an auxiliary relay is automatically switched on to control the operation of CNC machine 10. However, if the query whether X > Y asked at step 400 is answered in negative (NO), the process returns back to step 300 to continue comparing NEV voltage X with configured voltage Y in real-time, until an alarm is raised by the system 10 for real-time monitoring of the neutral earth condition and configured in accordance with the present invention.

WORKING of MECU

The working of the system for monitoring of the neutral earth condition in real-time and configured according to the present invention is described below:

• 230V AC and Neutral connected to MECU (Machine Earth Care Unit) 50 at input power.

• With help of a rectifier 14, AC voltage converted to DC and voltage steps down to 5 Volts DC to be supplied to the controller or comparator IC 32.

• Controller or comparator IC 32 compares the input neutral 11 and earth voltage 13 with the configured voltage Y.

• In case, the input neutral 11 and earth voltage 13 is greater than the configured voltage Y, the comparator IC 32 makes Relay 28 ON.

• This will start operation of the MIMIC 30 to sound a buzzer or a mixture of audible and visual alarm to alert the machine operator about high voltage.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The system for real-time monitoring of the neutral earth condition configured in accordance with the present invention has the following advantages:

• MECU (Machine Earth Care Unit) very simple, robust and very compact in construction.

• The voltage measurements are very precise, i.e. voltage is measured in mV and scanning time in milliseconds.

• The system is easy to configure and quite user friendly.

• Substantially enhances the safety of the machine and personnel thereabout is substantially.
• Offers a low-cost on-line system for voltage measurements in real-time.

• Offers a simple method for real-time monitoring and detection of neutral earth condition of machines/components.

In the previously detailed description, different features have been summarized for improving the conclusiveness of the representation in one or more examples. However, it should be understood that the above description is merely illustrative, but not limiting under any circumstances. It helps in covering all alternatives, modifications and equivalents of the different features and exemplary embodiments.

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. Many other examples are directly and immediately clear to the skilled person because of his/her professional knowledge in view of the above description.

These innumerable changes, variations, modifications, alterations may be made and/or integrations in terms of materials and method used may be devised to configure, manufacture and assemble various constituents, components, subassemblies and assemblies according to their size, shapes, orientations and interrelationships. Therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments.

The exemplary embodiments described in this specification are intended merely to provide an understanding of various manners in which this embodiment may be used and to further enable the skilled person in the relevant art to practice this invention. The description provided herein is purely by way of example and illustration.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps. In the claims and the description, the terms “containing” and “having” are used as linguistically neutral terminologies for the corresponding terms “comprising”.
The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention. Furthermore, the use of the term “one” shall not exclude the plurality of such features and components described.

Also, any reference herein to the terms ‘left’ or ‘right, ‘up’ or ‘down, or ‘top’ or ‘bottom’ are used as a matter of mere convenience and are determined by standing at the rear of the machine facing in its normal direction of travel.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

The various features and advantageous details are explained with reference to the non-limiting embodiment/s in the above description in accordance with the present invention. The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification.

Furthermore, the various components shown or described herein for any specific application of this invention can be widely known or used in the art by persons skilled in the art and each will likewise not therefore be discussed in significant detail. When referring to the figures, like parts are numbered the same in all of the figures. ,CLAIMS:We claim:

1. A system for real-time monitoring of the neutral earth condition of a machine/component connected thereto by detecting the difference between the neutral earth voltage (NEV) and a configured voltage predefined therefor and to indicate an improper neutral earth condition to the machine operator in order to take a remedial action to prevent any accident.

2. System for real-time monitoring of the neutral earth condition as claimed in claim 1, wherein said system is configured as a Machine Care Earth Unit (MECU), comprising:

• a step-down transformer;

• a bridge rectifier to convert AC voltage to DC voltage;

• a button for setting said configured voltage;

• a dual 7-segment display (SSD) for displaying said neutral earth voltage (NEV) and said configured voltage respectively; and

• an integrated circuit (IC) having a controller for detecting in real-time, the voltage difference between said neutral earth voltage (NEV) and said voltage configured for the neutral and earth terminals of said machine/component;

wherein said IC is activated whenever said neutral earth voltage (NEV) exceeds said configured voltage.

3. System as claimed in claim 2, wherein said step-down transformer is used to step down the machine/component voltage, preferably from 220V or 230V AC to 5V AC.

4. System as claimed in claim 3, wherein said bridge rectifier is used to convert said AC voltage to DC voltage to be supplied to said controller.

5. System as claimed in claim 2, wherein said IC is configured as an audio and visual alarm about any detected improper neutral earth condition.
6. System as claimed in claim 5, wherein said IC comprises:

• a respective neutral voltage and earthing voltage points connected to a means for comparing in real-time said neutral earth voltage (NEV) with said configured voltage;

• a respective 7-segment display (SSD) for displaying said neutral earth voltage (NEV) and said configured voltage;

• a button connected to said comparing means and a programming means for setting said configured voltage;

• a relay to be switched on by said comparing means,

wherein said IC comprises a Micro/Millimeter-wave Monolithic Integrated Circuit (MIMIC).

7. System as claimed in claim 6, wherein said relay is activated for starting said MIMIC, whenever said neutral earth voltage (NEV) is detected higher than said configured voltage to start said MIMIC.

8. System as claimed in claim 7, wherein said MIMIC is configured to issue an alarm for alerting the machine operator about the presence of an improper neutral earth condition in order to take a remedial action to prevent any accident.

9. System as claimed in claim 8, wherein said alarm is sounded by means of a buzzer or a mixture of audible and visual indication.

10. A method for real-time monitoring of the neutral earth condition of a machine/component connected thereto using the Machine Care Earth Unit (MECU) system as claimed in anyone of the claims 1 to 9, said method comprises the following method steps:

• connecting 220V/230V power supply and neutral thereof to said Machine Earth Care Unit (MECU) at input power;

• setting a predefined voltage Y configured by means of said programming means;

• stepping down the supply voltage from 220V/230V to 5V AC for supply to said controller;

• converting said AC into DC voltage by means of said rectifier;

• receiving the neutral earth voltage X from the machine and comparing said neutral earth voltage (NEV) X with said configured voltage Y;

• switching on a relay when said neutral earth voltage (NEV) X is detected to be higher than said configured voltage Y; and

• starting the operation of said MIMIC for issuing an alarm by means of a buzzer or a mixture of audible and visual alarm about the presence of an improper neutral earth condition;

whereby the machine operator takes a remedial action to prevent any accident, such as electrocution of the personnel present in the vicinity of said machine/component.

Dated: this 31st day of March 2017. SANJAY KESHARWANI
APPLICANT’S PATENT AGENT