Description:“A SYSTEM AND A METHOD FOR PROTECTING THE WELDING MACHINE FROM STRAY CURRENT FAILURES”
FIELD OF INVENTION
[0001] The present invention relates to a device for protecting welding machines from stray currents during welding. More particularly, a standalone device which can be integrated into any type of welding machine irrespective of its manufacturer, process technology or application.
BACKGROUND/PRIOR ART OF INVENTION
[0002] Steel alloys in various grades and sizes are used as raw materials by the heavy engineering sectors, particularly boiler manufacturers. Cutting, welding, cold and hot shaping, and other procedures are used to shape these steel alloys into final objects. The main application of welding is to fuse or unite different or similar pieces of metal. Pressurized water or steam is circulated inside hollow tubes manufactured of various alloy steel grades in thermal power plants, depending on the pressure and temperature the tubes must endure. Long serpentine coils or panels that make up the pressure portion components of a boiler are created by welding together alloy steel tubes, which are used as raw materials and come in different lengths. Depending on the requirements of the process, welding can be done manually, semi-automatically, or automatically. The procedures used in welding methodology are Gas Metal Arc Welding (GMAW/MIG), Gas Tungsten Arc Welding (GTAW/TIG), Submerged Arc Welding (SAW), and Manual Metal Arc Welding (MMAW). Each operation produces a welding arc between the parent metal and the welding electrode. When two conductors come into contact and are then kept apart by a tiny space of two to four millimeters such that the current flows through the air, an electric arc is created. The electric arc generates temperatures between 4000°C and 6000°C. The filler wire that is placed in the valley formed between the jobs that are being fused together is melted by this arc. For welding, the ends and edges of hollow tubes are butted together after being chamfered into grooves.
[0003] Aside from the processing technique they use, welding machines come in various sizes, forms, and capacities. These devices provide the electricity required for the arc welding procedure, which melts the electrode. Constant voltage and constant current power supplies are the most widely used power supply for welding. In arc welding, the voltage and current are closely correlated with the arc’s length and the quantity of heat input, respectively. Arc welding uses alternating current (A.C.) and direct current (D.C.). The inverter-type welding machine is the most widely utilized design due to developments in electronics technology. It transforms an A.C. power source into a lower useful output voltage, such as a 20V D.C. output from a 415V or 230V A.C. supply. Devices based on inverters convert power through a sequence of electronic parts. In contrast, a single, sizable transformer is the primary means of controlling the voltage in typical transformer-based devices. An inverter operates by raising the primary power supply’s frequency from 50Hz to 20,000–100,000Hz. Electronic switches—insulated-gate bipolar transistors, or IGBTs—are used for this purpose. They can quickly turn on and off the power—up to a millionth of a second. This method of regulating the power supply before it enters the transformer allows for a very considerable reduction in transformer size.
[0004] With a plethora of controls and parts to ensure the highest welding quality, modern welding machines are intricate electrical instruments. Because of this, they need to be protected and cared for. But because the devices are typically used in a variety of environmental settings, they need sufficient protection from their surroundings—both natural and man-made. The primary cause leading to breakdown or damage to these welding machines is stray currents. Stray currents refer to unintended or undesired and often small electrical currents that flow through unintended paths in a welding setup. These currents can occur due to improper grounding, poor insulation, high-frequency interference or other electrical faults in the welding system. They are challenging to monitor and control. Stray welding currents can be hazardous as they might cause electric shocks, damage electronic equipment, or lead to erratic welding performance. They can lead to issues such as electromagnetic interference (EMI), affecting nearby electronic devices and systems. This interference may manifest as noise or disruptions in sensitive equipment. Stray welding currents can pose safety risks to welders, equipment, and nearby individuals if not appropriately managed. They might cause electric shocks or affect the performance of the welding process, leading to poor-quality welds. Proper safety measures, such as maintaining good grounding of the welding equipment, adequate insulation, and using proper shielding techniques to minimize the effects of external high-frequency interference, are crucial to reduce stray welding currents and ensure a safe welding environment
[0005] The conventional method that is adopted has a few drawbacks which include
Conventional welding systems suffer from bulkiness, high power consumption, limited control, and maintenance demands. They struggle with arc stability, environmental sensitivity, and safety risks like electric shocks. Older models lack versatility, have inefficient power conversion, and incur long-term costs. These challenges highlight the need for more efficient, flexible, and safer welding technologies in modern industrial settings.
[0006] Therefore, it is quite evident that all of the above disclosures in the prior arts have drawbacks and thereby the method of present invention offers real-time monitoring and intervention, ensuring timely detection and mitigation of stray currents. It enhances safety by preventing damage to the welding machine and nearby equipment, regardless of technology or capacity, through automatic operation interruption and visual alerts. Thus, there is a pressing need to achieve the same.

OBJECTS OF THE INVENTION
[0007] Some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed herein below.
[0008] It is an object of the present subject matter to overcome the aforementioned and other drawbacks existing in the prior art systems and methods.
[0009] It is a principal object of the present subject matter to introduce a method and system for welding machines to mitigate failures caused by environmental stray currents during operation.
[0010] It is another significant object of the present subject matter to propose the method and system ensuring continuous operation of the device, with fast activation and ease of installation.
[0011] It is another significant object of the present subject matter to propose the method and system with imediate activation to safeguard welding machines from potential damage.
[0012] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taking into consideration with accompanied drawings in which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION
[0013] This summary is provided to introduce the concept that discloses a system and a method for protecting the welding machine from stray current failures. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor it is intended to be used to limit the scope of the claimed subject matter.

[0014] The present invention discloses a system and a method for protecting the welding machine from stray current failures. The system comprises of a cuboidal enclosure forming a protective housing assembly, a display unit integrated into the front face of the system, a control unit connected to the display unit for monitoring and operating the protection system, an alarm module connected to the control unit for providing feedback in case of abnormality, a reset switch connected to the control unit for resetting the system after exceeding tolerance levels, a terminal block connected to the control unit as an electrical interface connecting power and communication cables, a relay module connected to the control unit for controlling the welding machine based on monitored parameters, a potentiometer turn knob connected to the control unit serving as a present value input for the system, and an input power source derived from the welding machine for system operation.
[0015] To further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit the scope of the present subject matter.
[0016] 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 ACCOMPANYING DRAWINGS
[0017] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which
[0018] Fig. 1 illustrates the schematic diagram of a system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure;
[0019] Fig 2 illustrates the isometric view of a system for protecting the welding machine from stray current failures in accordance with the disclosure;
[0020] Fig 3 illustrates the front view of a system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure;
[0021] Fig 4 illustrates the flow chart for the operation of a system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure; and
[0022] Fig 5 illustrates the inverse time characteristic of the system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure.
[0023] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS
[0024] A few aspects of the present disclosure are explained in detail below with reference to the various figures. Example implementations are described to illustrate the disclosed subject matter, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a number of equivalent variations of the various features provided in the description that follows.
[0025] 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.
[0026] 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.
[0027] 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.
[0028] Various embodiments are further described herein with reference to the accompanying figures. It should be noted that the description and figures relate to exemplary embodiments and should not be construed as a limitation to the subject matter of the present disclosure. It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the subject matter of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the subject matter of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof. Yet further, for the sake of brevity, operation or working principles pertaining to the technical material that is known in the technical field of the present disclosure have not been described in detail so as not to unnecessarily obscure the present disclosure.
[0029] Fig. 1 illustrates the schematic diagram of a system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure. The invention relates to a system and a method for protecting the welding machine from stray current failures. The system(100)comprises of a cuboidal enclosure (1) forming a protective housing assembly, a display unit (2) integrated into the front face of the system(100), a control unit (6), connected to the display unit (2) for monitoring and operating the protection system, an alarm module (3) connected to the control unit (6) for providing feedback in case of abnormality, a reset switch (4), connected to the control unit (6) for resetting the system(100)after exceeding tolerance levels, a terminal block (7), connected to the control unit (6) as an electrical interface connecting power and communication cables, a relay module (9) connected to the control unit (6) for controlling the welding machine based on monitored parameters, a potentiometer turn knob (8) connected to the control unit (6) serving as a present value input for the system and an input power source (14) derived from the welding machine for system(100)operation. A plurality of feedback sensors, including a current sensor (12) for positive terminal monitoring and an additional current sensor (13) for negative terminal monitoring. A communication port (5) integrated into the front face of the system (100) for interaction with a welding machine.
[0030] The Cuboidal Enclosure (1) forms the protective housing assembly, providing physical protection to the internal components of the system (100). The display Unit (2) integrated into the system's front face, it allows for the visual monitoring of system status and parameters.
[0031] The control unit (6) is connected to the display unit (2), it serves as the central processing hub, monitoring and operating the protection system. It constantly evaluates current parameters during welding and provides feedback, including alarms or termination of operation, based on the severity of stray current inrush.
[0032] The alarm module (3) is connected to the control unit (6), it provides feedback in case of abnormalities. The alarm module (3) comprises a flashing LED light (10) for visual indication and a buzzer (11) for audio indication.
[0033] The reset switch (4) is connected to the control unit (6), it allows for manual resetting of the system after exceeding tolerance levels, ensuring system integrity and readiness. The terminal Block (7) is connected to the control unit (6), it serves as an electrical interface, connecting power and communication cables to the system.
[0034] The relay module (9) is connected to the control unit (6), it controls the welding machine based on monitored parameter activated by the control unit (6) when the stray current amplitude exceeds a present safety value, further providing a command to interrupt welding operations to safeguard the welding machine.
[0035] The potentiometer turn knob (8) is connected to the control unit
(6) serves as an input device for setting an allowable difference between welding current and return current. This compensates for measurement accuracy and processing timing discrepancies.
[0036] The input power source (14) is derived from the welding machine itself, it powers all components within the system (100), ensuring continuous operation without the need for external power sources.
[0037] The communication port (5) is integrated into the front face for interaction with a welding machine, facilitating data exchange and control commands between the system (100) and the welding machine.
[0038] The feedback sensors including a current sensor (12) for positive terminal monitoring and an additional current sensor (13) for negative terminal monitoring, enhancing system precision by providing real-time feedback on current parameters.
[0039] Fig 2 illustrates the isometric view of a system for protecting the welding machine from stray current failures in accordance with the disclosure. The system (100) comprises a metallic housing assembly in a cuboidal enclosure (1). The cubical enclosure (1) has a display screen on its front face, which forms the display Unit (2). An alarm in the form of a flashing light with a buzzer (3) is also provided for visual feedback to the operator in case of any abnormality. In case the protection device switches off the welding machine for exceeding tolerance levels of stray currents, the machine can be reset using the reset button (4) on the protection device. The system (100) interacts with the welding machine through a dedicated 9-pin communication port (5). The port (5) also provides the power supply required by the device for its operation.
[0040] Fig 3 illustrates the front view of a system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure. The control unit (6) runs the custom-made program for monitoring the stray currents during welding and controlling/protecting the welding machine from failure. The terminal block (7) acts as an electrical interface connecting power and communication cables between various elements and the control unit (6). The output cables of the 9-pin communication port (5) are also connected to the terminal block (7). The multi-turn potentiometer (8) provides the preset value input to the controller. The potentiometer (8) sets an allowable difference between the welding current and return current, which may occur due to the microcontroller’s measurement accuracy and processing timing, as the welding current will not be a uniform D.C. in nature. The relay module (9) acts as a switch to shut down the welding machine when the magnitude of stray currents exceeds the permissible value.
[0041] All the components in the device are powered by an input power source (14) from the welding machine itself. The source (14) powers all other components in the welding machine, like PCBs, sensors, switches, etc.
WORKING OF EMBODIEMENT
[0042] The method for protecting a welding machine from stray currents comprises of the following steps
• Monitoring the magnitudes of welding current (W.C.) and the return currency (R.C.)
• Setting a tolerance value (T) using a potentiometer turn knob (8)
• Resetting a counter value in case of abnormalities and adding a delay to ensure free flow of machine operation
• Checking the severity of stray current inrush in multiples of 15
• Activating an alarm module (3) for every instance the difference between W.C. and R.C. exceeds T
• Issuing a shutdown command to the welding machine through a relay module (9) when the counter value exceeds a predefined threshold
• Resetting the welding machine after rectifying the cause of stray currents using a reset button (4).
[0043] The severity of stray current inrush is measured by calculating the difference of W.C. from R.C. and T, i.e., WC-RC-T. The system (100) operates with an inverse time characteristic, shutting down the welding machine faster with an increase in the difference between the welding current and return current.
[0044] Fig 4 illustrates the flow chart for the operation of a system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure. The control unit (6) continuously monitors the welding current (W.C.) and return current (R.C.) magnitudes from the current sensors (12, 13) in the machine. The tolerance value (T) is set using the potentiometer (8). A counter value in the controller’s (6) program is used to increment in case of any abnormalities. As long as the difference between W.C. and R.C. is higher than the permissible tolerance, the control unit (6) keeps resetting the counter value and adds a delay of 300ms to ensure the free flow of machine operation. When the difference between W.C. and R.C. exceeds T, the control unit (6) checks the severity of stray current inrush in multiples of 15 (15, 30, 45, and 60). It operates with an inverse time characteristic, meaning the higher the difference between the welding current and the return current, the faster it will shut down the machine.
ADVANTAGES OF THE INVENTION
[0045] The proposed system and method have the following advantages over the contemporary system:
• Universal Compatibility: The protection system integrates seamlessly into any welding machine, irrespective of manufacturer, technology, or application, enhancing versatility.
• Continuous Monitoring: An intelligent controller continuously monitors welding and return currents, promptly detecting any abnormal deviations.
• Immediate Protection: Upon detecting stray currents exceeding permissible limits, the system immediately signals an interrupt command, halting machine operation to prevent damage and ensure personnel safety.
• Audiovisual Feedback: The system provides clear audiovisual alerts to operators, enhancing situational awareness and facilitating timely intervention.
• Ease of Operation: Featuring a user-friendly interface with a dedicated display, the system simplifies monitoring and fault management during welding processes.
• Reset Capability: Operators or trained personnel can easily reset the system after rectifying abnormalities, minimizing downtime and optimizing productivity.
• Protection against Various Faults: Safeguards welding machines from a broad spectrum of faults caused by stray currents, ensuring equipment integrity and welding process efficiency
TEST RESULT
[0046] Fig 5 illustrates the inverse time characteristic of the system for protecting the welding machine from stray current failures in accordance with an embodiment of the present disclosure. The time versus current curve depicting the characteristic is shown in Figure 5. The severity is measured by calculating the difference of W.C. from R.C. and T, that is, WC-RC-T. The counter is incremented each time with a predefined weight value according to the magnitude of the stray currents. The control unit (6) activates the alarm module (3) for every instance the difference between W.C. and R.C. exceeds T. The control unit (6) issues a shutdown command to the welding machine through the relay module (9) when the counter value exceeds 60. The welding machine can be reset with the reset button (4) after rectifying the cause of stray currents
[0047] The above description does not provide specific details of the manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.
[0048] Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[0049] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[0050] It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.
, Claims:We Claim:
1. A system (100) for protecting the welding machine from stray current failures, the system (100) comprising:
a cuboidal enclosure (1) forming a protective housing assembly;
a control unit (6), connected to a display unit (2) for monitoring and operating the protection system;
an alarm module (3) connected to the control unit (6) for providing feedback in case of abnormality;
a reset switch (4), connected to the control unit (6) for resetting the system (100) after exceeding tolerance levels;
a terminal block (7), connected to the control unit (6) as an electrical interface connecting power and communication cables;
a relay module (9) connected to the control unit (6) for controlling the welding machine based on monitored parameters;
a potentiometer turn knob (8) connected to the control unit (6) serving as a present value input for the system; and
an input power source (14) derived from the welding machine for system (100) operation.
2. The system (100) as claimed in the claim 1, wherein the display unit (2) integrated into the front face of the system (100).
3. The system (100) as claimed in the claim 1, wherein the alarm module (3) comprises a flashing LED light (10) for visual indication and a buzzer (11) for audio indication.
4. The system (100) as claimed in the claim 1, wherein a plurality of feedback sensors, including a current sensor (12) are provided for positive terminal monitoring and an additional current sensor (13) for negative terminal monitoring.
5. The system (100) as claimed in the claim 1, wherein a communication port (5) is integrated into the front face of the system (100) for interaction with a welding machine.
6. The system (100) as claimed in the claim 1, wherein the control unit (6) is configured to constantly monitor current parameters during welding and provide feedback, including alarms for termination of operation, based on the severity of stray current inrush.
7. The system (100) as claimed in the claim 1, wherein the relay module (9) is activated by the control unit (6) when the stray current amplitude exceeds a present safety value, and the relay module provides a command to interrupt welding operations to safeguard the welding machine.
8. The system (100) as claimed in the claim 1, wherein the potentiometer turn knob (8) sets an allowable difference between welding current and return current, compensating for microcontroller measurement accuracy and processing timing.
9. A method for protecting a welding machine from stray currents, the method comprising steps of:
-monitoring the magnitudes of welding current (W.C.) and the return current (R.C.);
-setting a tolerance value (T) using a potentiometer turn knob (8);
-resetting a counter value in case of abnormalities and adding a delay to ensure free flow of machine operation;
-checking the severity of stray current inrush in multiples of 15;
-activating an alarm module (3) for every instance the difference between W.C. and R.C. exceeds T;
-issuing a shutdown command to the welding machine through a relay module (9) when the counter value exceeds a predefined threshold; and
-resetting the welding machine after rectifying the cause of stray currents using a reset button (4).
10. The method as claimed in the claim 9, wherein the severity of stray current inrush is measured by determining the difference of W.C. from R.C. and T, i.e., WC-RC-T.

11. The method as claimed in the claim 9, wherein the system (100) operates with an inverse time characteristic, shutting down the welding machine faster with an increase in the difference between the welding current and return current.