Arc fault detection device for low voltage circuit breakers

Abstract

The application discloses an arc fault detection device for a low-voltage circuit breaker and relates to the technical field of low-voltage circuit breaker fault detection.The device comprises a workbench, wherein an elevated platform is installed on a reference plate of the workbench;an infrared temperature measurement probe is installed on a first supporting rod of a first support;an industrial frequency magnetic field measuring device is installed on a second supporting rod of a second support;first and second inclined surfaces are symmetrically arranged on the left and right sides of a third support;third and fourth supporting rods are respectively installed on the first and second inclined surfaces;first and second noise detection probes are respectively installed on the inner ends of the third and fourth supporting rods;and a fifth supporting rod is arranged between the third and fourth supporting rods, and a third noise detection probe is installed on the bottom end of the fifth supporting rod.The device eliminates the blind area of traditional single-point detection, can capture complete high-frequency noise spectrum radiated by various types of fault arcs in the circuit breaker without dead angles, ensures complete extraction of characteristic signals, and avoids misjudgment caused by signal attenuation or directionality omission.

Description

Technical Field

[0001] This invention relates to the field of low-voltage circuit breaker fault detection technology, and specifically discloses an arc fault detection device for low-voltage circuit breakers. Background Technology

[0002] Current circuit breakers operate based on current amplitude, and in some cases, they cannot detect fault arcs with small currents but highly concentrated energy and extremely high temperatures. These arcs can ignite surrounding flammable materials, causing damage to low-voltage lines and electrical equipment. To verify the reliability of low-voltage circuit breakers, arc fault detection is required before installation. Generally, arc fault detection technology uses high-frequency sensors and microprocessors to analyze the high-frequency noise, zero-wave characteristics, and random distortion of the current waveform, accurately distinguishing between harmless arcs generated during normal operation and dangerous fault arcs. If the arc fault detection fails to meet installation standards, the low-voltage circuit breaker needs to be replaced to improve the safety of the low-voltage power distribution system and protect personal and property safety.

[0003] In arc fault detection of low-voltage circuit breakers, the acquisition of high-frequency noise signals is a core component. Defects in this component will directly lead to a significant reduction in detection reliability. The essential characteristic of a fault arc is that its current waveform contains a large number of unique high-frequency noise components. Current detection equipment often employs a unidirectional noise acquisition device layout, which has a limited detection angle and makes it difficult to comprehensively capture the complete noise spectrum excited by all types and locations of arcs in the low-voltage circuit breaker, easily creating detection blind spots. Furthermore, some fault arcs occurring in locations opposite to the acquisition point or with severe shielding may experience severe attenuation or distortion of their high-frequency signals, leading to incomplete feature extraction and significantly increasing the risk of misjudgment. Summary of the Invention

[0004] To address the high risk of misjudgment in current arc fault detection processes for low-voltage circuit breakers, this invention provides an arc fault detection device for low-voltage circuit breakers.

[0005] To address the above problems, the present invention provides the following technical solution:

[0006] An arc fault detection device for a low-voltage circuit breaker includes a workbench with a reference plate fixedly mounted on it. An extension platform for placing the low-voltage circuit breaker is mounted on the reference plate. Multiple fastening clamps mounted on the reference plate are arranged around the extension platform to securely assemble the low-voltage circuit breaker with the extension platform. A first support and a second support are respectively arranged on both sides of the reference plate, both of which are securely connected to the workbench. A first support rod that moves obliquely is mounted on the first support rod, and an infrared temperature probe is fixedly mounted on the inner end of the first support rod. A second support rod that moves obliquely is mounted on the second support rod. A power frequency magnetic field measuring device is fixedly installed at the inner end of the reference plate; a third bracket is provided on the rear side of the reference plate, and a first inclined plane and a second inclined plane are symmetrically arranged on both sides of the third bracket. A third support rod and a fourth support rod that move obliquely are respectively installed on the first inclined plane and the second inclined plane. A first noise detection probe and a second noise detection probe are fixedly installed at the inner ends of the third support rod and the fourth support rod, respectively. A fifth support rod that moves vertically is provided between the third support rod and the fourth support rod. A third noise detection probe is fixedly installed at the bottom end of the fifth support rod. The first noise detection probe, the second noise detection probe and the third noise detection probe are all used to detect the fault noise of the low voltage circuit breaker.

[0007] Preferably, two reference corner blocks are fixedly installed on the work platform, a reference plate is arranged between the two reference corner blocks, two handles are fixedly installed on the reference plate, multiple support columns are fixedly installed at the bottom of the elevation platform, the bottom ends of the support columns are fastened to the reference plate, an installation plate is fixedly installed on the elevation platform, and a slot for fixing a low-voltage circuit breaker is provided in the installation plate; a power supply assembly is fixedly installed on the reference plate, and the power supply assembly is electrically connected to the low-voltage circuit breaker.

[0008] Preferably, multiple limiting plates are fixedly installed around the raised platform, and multiple vertically arranged first cylinders are fixedly installed on the reference plate. The fastening clamp includes a first foot plate and a second foot plate. The first foot plate and the second foot plate are arranged vertically and are both fastened to the piston rod of the first cylinder. The included angle between the first foot plate, the second foot plate and the piston rod is °.

[0009] Preferably, the first bracket is vertically arranged, and a first inclined plate is fixedly installed on the top of the first bracket. A second cylinder and a first rod seat are fixedly installed on the first inclined plate. The first support rod and the piston rod of the second cylinder are arranged in parallel. The piston rods of the first support rod and the second cylinder are both slidably engaged with the first rod seat. The tail of the infrared temperature measuring probe is fastened to the first support rod and the piston rod of the second cylinder. The probe part of the tail of the infrared temperature measuring probe faces the reference plate.

[0010] Preferably, the second bracket is arranged at an angle, and a third cylinder is fixedly installed on the inner side of the second bracket. The second support rod is arranged parallel to the piston rod of the third cylinder, and the second support rod and the piston rod of the third cylinder are fastened together by a first connecting plate. The probe of the power frequency magnetic field measuring device faces the reference plate.

[0011] Preferably, a first cylinder seat and a second cylinder seat are respectively fixedly installed on the first inclined surface and the second inclined surface, and a fourth cylinder and a fifth cylinder are respectively fixedly installed in the first cylinder seat and the second cylinder seat; the third support rod is arranged parallel to the piston rod of the fourth cylinder, and the third support rod and the piston rod of the fourth cylinder are fastened together by a second connecting plate, and the second connecting plate is fastened together with a first noise detection probe; the fourth support rod is arranged parallel to the piston rod of the fifth cylinder, and the fourth support rod and the piston rod of the fifth cylinder are fastened together by a third connecting plate, and the third connecting plate is fastened together with a second noise detection probe.

[0012] Preferably, a third cylinder seat is fixedly installed on the inner side of the top of the third bracket, a sixth cylinder is fixedly installed inside the third cylinder seat, the fifth support rod is arranged parallel to the piston rod of the sixth cylinder, the fifth support rod and the piston rod of the sixth cylinder are fastened together by a fourth connecting plate, and the fourth connecting plate is fastened together with the third noise detection probe.

[0013] Preferably, a horizontally arranged fourth cylinder seat is fixedly installed on the second inclined surface, a seventh cylinder is fixedly installed inside the fourth cylinder seat, a sixth support rod arranged parallel to the piston rod of the seventh cylinder is slidably installed inside the fourth cylinder seat, the sixth support rod and the piston rod of the seventh cylinder are fastened together by a fifth connecting plate, and a fourth noise detection probe is fixedly installed on the inner side of the fifth connecting plate.

[0014] Preferably, a fence frame is fixedly installed on the work platform. The fence frames are arranged around the first support, the second support, and the third support. Two manual doors are installed on the rear side of the fence frame, and an observation window is provided on the front side of the fence frame. An plexiglass can be fixedly installed inside the observation window.

[0015] Preferably, a PLC main control box, start / stop button, emergency stop button, parameter knob, and reset button are fixedly installed on the front side of the fence frame; a display is fixedly installed on the side of the fence frame; and an alarm flasher is fixedly installed on the top of the fence frame.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. This invention sets up a high-frequency noise sensor array by setting up a first, second, third, and fourth noise detection probe arranged at multiple angles. Each noise detection probe is driven by its own independent cylinder, which can precisely control its relative distance and angle with the low-voltage circuit breaker under test. The above-mentioned multi-directional spatial layout eliminates the blind spots of traditional single-point detection and can capture the complete high-frequency noise spectrum radiated by various types of fault arcs at various locations inside the circuit breaker without dead angles. This ensures the complete extraction of characteristic signals and avoids misjudgment caused by signal attenuation or directional omission from the hardware source.

[0018] 2. This invention utilizes an inclined power frequency magnetic field measuring device and a radially movable infrared temperature probe to form a multi-physical quantity collaborative sensing layer. This layer can provide evidence for high-frequency noise diagnosis from two dimensions: current waveform distortion and temperature rise characteristics. Furthermore, it achieves cross-validation by fusing multiple parameters of current, electromagnetic, and temperature. All the aforementioned sensing data are centrally collected and analyzed by intelligent algorithms in a PLC control box, greatly improving the system's anti-interference capability and decision reliability.

[0019] 3. By setting up a closed-loop fence and card slot, this invention ensures the consistency of the test environment and the stability of the device under test, further reducing the measurement error introduced by external interference. This forms a high-precision closed-loop detection system, significantly reducing false alarm and missed alarm rates, and providing a comprehensive and highly reliable assessment guarantee for the safety of low-voltage circuit breakers. Attached Figure Description

[0020] To more clearly illustrate the technical solution of the present invention, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall device structure of the present invention. Figure 1 ;

[0022] Figure 2 This is a schematic diagram of the overall device structure of the present invention. Figure 2 ;

[0023] Figure 3 This is a schematic diagram of the installation structure of the first bracket, the second bracket, and the third bracket of the present invention;

[0024] Figure 4 This is a schematic diagram of the mounting structure of the mounting plate and the first cylinder of the present invention;

[0025] Figure 5 This is a schematic diagram of the infrared temperature probe installation structure of the present invention;

[0026] Figure 6 This is a schematic diagram of the installation structure of the power frequency magnetic field measuring device of the present invention;

[0027] Figure 7 This is a schematic diagram of the installation structure of the first noise detection probe, the second noise detection probe, the third noise detection probe, and the fourth noise detection probe of the present invention.

[0028] Figure 8 This is a schematic diagram of the installation structure of the PLC main control box of the present invention;

[0029] In the diagram: 1. Workbench, 2. Base plate, 3. Elevating platform, 4. First support, 5. Second support, 6. First support rod, 7. Infrared temperature probe, 8. Second support rod, 9. Power frequency magnetic field measuring device, 10. Third support, 11. First inclined plane, 12. Second inclined plane, 13. Third support rod, 14. Fourth support rod, 15. First noise detection probe, 16. Second noise detection probe, 17. Fifth support rod, 18. Third noise detection probe, 19. Base corner block, 20. Handle, 21. Support column, 22. Mounting plate, 23. Slot, 24. Power assembly, 25. Limiting plate, 26. First cylinder, 27. First foot plate, 28. Second foot plate, 29. First inclined plate, 3 0. Second cylinder, 31. First rod holder, 32. Third cylinder, 33. First connecting plate, 34. First cylinder holder, 35. Second cylinder holder, 36. Fourth cylinder, 37. Fifth cylinder, 38. Second connecting plate, 39. Third connecting plate, 40. Third cylinder holder, 41. Sixth cylinder, 42. Fourth connecting plate, 43. Fourth cylinder holder, 44. Seventh cylinder, 45. Sixth support rod, 46. Fifth connecting plate, 47. Fourth noise detection probe, 48. Fence frame, 49. Hand-operated door, 50. Observation window, 51. PLC main control box, 52. Start / stop button, 53. Emergency stop button, 54. Parameter knob, 55. Reset button, 56. Display, 57. Warning flasher. Detailed Implementation

[0030] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0031] This specific embodiment provides an arc fault detection device for low-voltage circuit breakers, such as... Figures 1-8As shown, the device includes a workbench 1 with multiple casters at its bottom for easy movement. The workbench 1 has a cavity for storing power supplies and control equipment, and also facilitates wiring. A horizontal plate is mounted above the workbench 1, serving as the arc fault detection base for the device. A closed enclosure 48 is fixedly installed on the workbench 1, surrounding the horizontal plate. Two pull-out doors 49 are installed at the rear of the enclosure 48, allowing operators to easily place the low-voltage circuit breaker into it. An observation window 50 is located at the front of the enclosure 48, with a piece of plexiglass fixedly installed inside, allowing operators to observe the arc fault detection process of the low-voltage circuit breaker in real time.

[0032] A reference plate 2 is fixedly installed on the horizontal plate of the workbench 1. Reference corner blocks 19 are provided on both sides of the reference plate 2, and both reference corner blocks 19 are firmly connected to the horizontal plate of the workbench 1, thereby further fixing the installation position of the reference plate 2 and improving its stability. Two symmetrically arranged handles 20 are fixedly installed on the reference plate 2, facilitating the operator to place the reference plate 2 into the guardrail frame 48. Multiple support columns 21 are fixedly installed on the reference plate 2, and a raising platform 3 is installed above the support columns 21, creating a gap between the raising platform 3 and the reference plate 2. An installation plate 22 is fixedly installed on the raising platform 3, and multiple limiting plates 25 are fixedly installed around the raising platform 3, which can be used to further fix the installation plate 22. A slot 23 is provided inside the installation plate 22, the contour of which is adapted to the shape of the low-voltage circuit breaker, thereby fixing the low-voltage circuit breaker on the installation plate 22. A power supply assembly 24 is fixedly installed on the reference plate 2. The power supply assembly 24 can be electrically connected to the low-voltage circuit breaker, thereby providing the low-voltage circuit breaker with real-time power supply.

[0033] The reference plate 2 is fixedly mounted with multiple vertically arranged first cylinders 26, which are arranged around the riser platform 3. The piston rods of the first cylinders 26 are fastened to first foot plates 27 and second foot plates 28. The first foot plates 27 and second foot plates 28 are arranged vertically and simultaneously fastened to the piston rods of the first cylinders 26. The first foot plates 27 and second foot plates 28 together form a fastening clamp, facilitating the fastening assembly of the low-voltage circuit breaker to the riser platform 3 and improving the stability of the low-voltage circuit breaker during arc fault detection. The included angle between the first foot plates 27 and second foot plates 28 is 90°.

[0034] A first bracket 4 and a second bracket 5 are respectively provided on the left and right sides of the reference plate 2. The bottom of the first bracket 4 is fastened to the horizontal plate of the workbench 1. The first bracket 4 is vertically arranged, and a first inclined plate 29 is fixedly installed on the top of the first bracket 4. A second cylinder 30 and a first rod seat 31 are fixedly installed on the first inclined plate 29. The piston rod end of the second cylinder 30 faces the reference plate 2. A first support rod 6 is slidably installed in the first rod seat 31. The first support rod 6 is arranged parallel to the piston rod of the second cylinder 30. The piston rod of the second cylinder 30 is slidably engaged with the first rod seat 31. An infrared temperature probe 7 is fastened together to the first support rod 6 and the piston rod of the second cylinder 30. The probe end of the infrared temperature probe 7 faces the reference plate 2, which facilitates real-time detection of the internal and external temperatures of the low-voltage circuit breaker during arc fault detection, providing accurate temperature parameters for arc fault detection.

[0035] The second bracket 5 is arranged at an angle. A third cylinder 32 is fixedly installed on the inner side of the second bracket 5. A second support rod 8 is slidably installed inside the second bracket 5. The second support rod 8 is arranged parallel to the piston rod of the third cylinder 32. The piston rod of the third cylinder 32 is slidably engaged with the second bracket 5. The second support rod 8 and the piston rod of the third cylinder 32 are fastened together by a first connecting plate 33. A power frequency magnetic field measuring device 9 is fixedly installed on the first connecting plate 33. The probe of the power frequency magnetic field measuring device 9 faces the reference plate 2. The power frequency magnetic field measuring device 9 can accurately capture the zero-current phenomenon unique to fault arcs. By collecting and analyzing the harmonic components of the fundamental current, it can effectively distinguish between the interference generated by normal equipment switching and the harmonics of real faults, thereby significantly improving the anti-interference capability of the detection algorithm, reducing misjudgments, and ensuring the accuracy and reliability of arc fault judgment.

[0036] A third support 10 is provided on the rear side of the reference plate 2. A first inclined surface 11 and a second inclined surface 12 are symmetrically arranged on the left and right sides of the third support 10. A first cylinder seat 34 and a second cylinder seat 35 are respectively fixedly installed on the first inclined surface 11 and the second inclined surface 12, arranged symmetrically. A fourth cylinder 36 and a fifth cylinder 37 are respectively fixedly installed inside the first cylinder seat 34 and the second cylinder seat 35; the piston rod ends of the fourth cylinder 36 and the fifth cylinder 37 both face the reference plate 2. A third support rod 13 is slidably installed inside the first cylinder seat 34. The third support rod 13 is arranged parallel to the piston rod of the fourth cylinder 36, and the third support rod 13 and the piston rod of the fourth cylinder 36 are fastened together by a second connecting plate 38. A first noise detection probe 15 is fixedly installed on the second connecting plate 38. A fourth support rod 14 is slidably installed inside the second cylinder seat 35. The fourth support rod 14 is arranged parallel to the piston rod of the fifth cylinder 37. The fourth support rod 14 and the piston rod of the fifth cylinder 37 are fastened together by a third connecting plate 39. A second noise detection probe 16 is fixedly installed on the third connecting plate 39. The detection heads of both the first noise detection probe 15 and the second noise detection probe 16 face the reference plate 2.

[0037] A third cylinder seat 40 is fixedly installed on the inner side of the top of the third support 10. A fifth support rod 17 is slidably installed inside the third cylinder seat 40. The fifth support rod 17 is arranged vertically. A sixth cylinder 41 is fixedly installed inside the third cylinder seat 40. The piston rods of the fifth support rod 17 and the sixth cylinder 41 are arranged parallel to each other. The fifth support rod 17 and the piston rods of the sixth cylinder 41 are fastened together by a fourth connecting plate 42. A third noise detection probe 18 is fixedly installed at the bottom of the fourth connecting plate 42. The detection head of the third noise detection probe 18 faces the reference plate 2.

[0038] A fourth cylinder seat 43 is fixedly installed on the second inclined plane 12. A seventh cylinder 44 is fixedly installed inside the fourth cylinder seat 43. A sixth support rod 45, which is parallel to the piston rod of the seventh cylinder 44, is slidably installed inside the fourth cylinder seat 43. The sixth support rod 45 and the piston rod of the seventh cylinder 44 are fastened together by a fifth connecting plate 46. A fourth noise detection probe 47 is fixedly installed on the inner side of the fifth connecting plate 46. The fourth noise detection probe 47 faces the reference plate 2.

[0039] In addition, a PLC main control box 51, a start / stop button 52, an emergency stop button 53, a parameter knob 54, and a reset button 55 are fixedly installed on the front side of the fence frame 48. All of these components are arranged above the observation window 50. The PLC main control box 51 collects and integrates data from all lower-level components via a communication network, including the status and alarm information of the low-voltage circuit breaker. The start / stop button 52, emergency stop button 53, parameter knob 54, and reset button 55 facilitate operator control of the arc fault detection progress. A display 56 is fixedly installed on the side of the fence frame 48, which displays various detection parameters of the entire device in real time. A warning flasher 57 is fixedly installed on the top of the fence frame 48, which releases a warning signal when the low-voltage circuit breaker detection fails to meet the standard, thus providing a warning to the operator.

[0040] The working principle of this invention is as follows:

[0041] Operators can place the low-voltage circuit breaker in the slot 23 of the mounting plate 22 and send it into the slot from the rear of the fence frame 48 through the handle 20. By controlling the first cylinder 26, the first foot plate 27 and the second foot plate 28 are used to fix the low-voltage circuit breaker, so that the low-voltage circuit breaker is stably placed on the reference plate 2.

[0042] When operators perform arc fault detection on a low-voltage circuit breaker, they connect the power supply assembly 24 to the low-voltage circuit breaker to energize it. Operators can adjust the energizing voltage of the low-voltage circuit breaker using the parameter knob 54. After the low-voltage circuit breaker is energized, the infrared temperature probe 7 can detect the internal and external temperatures of the circuit breaker in real time. Operators can further adjust the distance between the infrared temperature probe 7 and the low-voltage circuit breaker by controlling the second cylinder 30 to output more reliable temperature parameters. The first noise detection probe 15, the second noise detection probe 16, and the third noise detection probe 18 can detect noise from the low-voltage circuit breaker from multiple angles. The distances between these probes and the low-voltage circuit breaker are adjusted by controlling the fourth cylinder 36, the fifth cylinder 37, and the sixth cylinder 41, respectively, making the extracted noise parameters more reliable. Operators can use these noise parameters to determine whether an arc fault has occurred in the low-voltage circuit breaker.

[0043] Meanwhile, the power frequency magnetic field measuring instrument 9 can accurately capture the unique zero-current phenomenon of fault arc. By collecting and analyzing the harmonic components of the fundamental current, it can effectively distinguish between the interference generated by normal equipment switching and the harmonics of real faults. Combined with the noise parameters detected by various noise detection probes, it can accurately determine whether there is a fault in the low-voltage circuit breaker, thereby improving the accuracy and reliability of arc fault judgment.

[0044] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An arc fault detection device for low-voltage circuit breakers, comprising a workbench (1), characterized in that, A reference plate (2) is fixedly installed on the workbench (1). An elevation platform (3) for placing a low-voltage circuit breaker is installed on the reference plate (2). Multiple fastening clamps installed on the reference plate (2) are provided around the elevation platform (3). The fastening clamps are used to fasten the low-voltage circuit breaker to the elevation platform (3). A first bracket (4) and a second bracket (5) are respectively provided on both sides of the reference plate (2). The first bracket (4) and the second bracket (5) are both fastened to the workbench (1). A first support rod (6) that moves obliquely is provided on the first support rod (4). An infrared temperature probe (7) is fixedly installed on the inner end of the first support rod (6). A second support rod (8) that moves obliquely is provided on the second support rod (5). A power frequency magnetic field measuring instrument (9) is fixedly installed on the inner end of the second support rod (8). The reference plate ( 2) A third support (10) is provided on the rear side. A first inclined plane (11) and a second inclined plane (12) are symmetrically arranged on both sides of the third support (10). A third support rod (13) and a fourth support rod (14) that move obliquely are respectively installed on the first inclined plane (11) and the second inclined plane (12). A first noise detection probe (15) and a second noise detection probe (16) are respectively fixedly installed at the inner ends of the third support rod (13) and the fourth support rod (14). A fifth support rod (17) that moves vertically is provided between the third support rod (13) and the fourth support rod (14). A third noise detection probe (18) is fixedly installed at the bottom end of the fifth support rod (17). The first noise detection probe (15), the second noise detection probe (16), and the third noise detection probe (18) are all used to detect the fault noise of the low-voltage circuit breaker.

2. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, Two reference corner blocks (19) are fixedly installed on the workbench (1). The reference plate (2) is arranged between the two reference corner blocks (19). Two handles (20) are fixedly installed on the reference plate (2). Multiple support columns (21) are fixedly installed at the bottom of the elevation platform (3). The bottom end of the support column (21) is tightly connected to the reference plate (2). An installation plate (22) is fixedly installed on the elevation platform (3). A slot (23) for fixing a low-voltage circuit breaker is provided in the installation plate (22). A power supply assembly (24) is fixedly installed on the reference plate (2). The power supply assembly (24) is electrically connected to the low-voltage circuit breaker.

3. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, Multiple limiting plates (25) are fixedly installed around the raised platform (3). Multiple vertically arranged first cylinders (26) are fixedly installed on the reference plate (2). The fastening fixture includes a first foot plate (27) and a second foot plate (28). The first foot plate (27) and the second foot plate (28) are arranged vertically and are both fastened to the piston rod of the first cylinder (26). The included angle between the first foot plate (27) and the second foot plate (28) is 90°.

4. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, The first bracket (4) is vertically set. A first inclined plate (29) is fixedly installed on the top of the first bracket (4). A second cylinder (30) and a first rod seat (31) are fixedly installed on the first inclined plate (29). The first support rod (6) and the piston rod of the second cylinder (30) are arranged in parallel. The piston rods of the first support rod (6) and the second cylinder (30) are both slidably engaged with the first rod seat (31). The tail of the infrared temperature probe (7) is tightly connected to the piston rods of the first support rod (6) and the second cylinder (30). The probe part of the tail of the infrared temperature probe (7) faces the reference plate (2).

5. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, The second bracket (5) is arranged at an angle. A third cylinder (32) is fixedly installed on the inner side of the second bracket (5). The second support rod (8) is arranged parallel to the piston rod of the third cylinder (32). The second support rod (8) and the piston rod of the third cylinder (32) are fastened together by the first connecting plate (33). The probe of the power frequency magnetic field measuring instrument (9) faces the reference plate (2).

6. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, The first inclined surface (11) and the second inclined surface (12) are respectively fixedly installed with inclined first cylinder seat (34) and second cylinder seat (35), and the first cylinder seat (34) and the second cylinder seat (35) are respectively fixedly installed with fourth cylinder (36) and fifth cylinder (37); the third support rod (13) is arranged parallel to the piston rod of the fourth cylinder (36), and the third support rod (13) and the piston rod of the fourth cylinder (36) are fastened together by the second connecting plate (38), and the second connecting plate (38) is fastened together with the first noise detection probe (15); the fourth support rod (14) is arranged parallel to the piston rod of the fifth cylinder (37), and the fourth support rod (14) and the piston rod of the fifth cylinder (37) are fastened together by the third connecting plate (39), and the third connecting plate (39) is fastened together with the second noise detection probe (16).

7. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, The third cylinder seat (40) is fixedly installed on the inner side of the top of the third bracket (10). The sixth cylinder (41) is fixedly installed inside the third cylinder seat (40). The fifth support rod (17) is arranged parallel to the piston rod of the sixth cylinder (41). The fifth support rod (17) and the piston rod of the sixth cylinder (41) are fastened together by the fourth connecting plate (42). The fourth connecting plate (42) is fastened together with the third noise detection probe (18).

8. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, A horizontally arranged fourth cylinder seat (43) is fixedly installed on the second inclined plane (12). A seventh cylinder (44) is fixedly installed inside the fourth cylinder seat (43). A sixth support rod (45) arranged parallel to the piston rod of the seventh cylinder (44) is slidably installed inside the fourth cylinder seat (43). The sixth support rod (45) and the piston rod of the seventh cylinder (44) are fastened together by a fifth connecting plate (46). A fourth noise detection probe (47) is fixedly installed on the inner side of the fifth connecting plate (46).

9. The arc fault detection device for low-voltage circuit breakers according to claim 1, characterized in that, The workbench (1) is fixedly installed with a fence frame (48). The fence frames (48) are arranged around the first support (4), the second support (5), and the third support (10). Two hand-operated doors (49) are installed on the rear side of the fence frame (48). An observation window (50) is provided on the front side of the fence frame (48). An organic glass can be fixedly installed inside the observation window (50).

10. The arc fault detection device for low-voltage circuit breakers according to claim 9, characterized in that, The front side of the fence frame (48) is fixedly equipped with a PLC main control box (51), a start / stop button (52), an emergency stop button (53), a parameter knob (54), and a reset button (55). The side of the fence frame (48) is fixedly equipped with a display (56), and the top of the fence frame (48) is fixedly equipped with a warning flasher (57).

Images