AC residual current monitoring device

Abstract

According to the AC residual current monitoring device designed by the utility model, when the internal temperature of the shell rises, the air bag expands and becomes large, the sliding piece is pushed to drive the contact block to abut against the electromagnetic button, the electromagnetic button starts the motor, the nut drives the connecting piece and the plugging piece to move downwards, the two heat dissipation openings can be opened, and then the fan is started in a matched manner; when the AC residual current monitoring device does not need to be used, the internal temperature of the shell is reduced at the moment, similarly, the air bag can be shrunk, the contact block is separated from the electromagnetic button, the electromagnetic button enables the motor driving shaft to rotate reversely at the moment, and the heat dissipation effect can be achieved. Therefore, external dust can be prevented from entering the shell, and the service life of the AC residual current monitoring device can be prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of current monitoring, in particular to an AC residual current monitoring device. Background Art

[0002] In order to avoid the problems of fire accidents such as low-voltage AC residual current high-resistance grounding and overload that may cause fire accidents in station equipment and cable trenches, low-voltage AC power supply systems in power plants and substations are usually equipped with low-voltage AC residual current monitoring devices to improve the safety of the operation of the main equipment in the station. The AC residual current monitoring device can also be widely used in AC power supply in power distribution sites such as construction and real estate, rail transit, steel industry, and chemical industry, and can also be used with an integrated power supply monitoring system.

[0003] However, in order to quickly dissipate the heat generated by the internal components of the existing AC residual current monitoring device, a fan is usually installed inside the AC residual current monitoring device, and then the heat is dissipated through the heat dissipation holes. Although this has a certain heat dissipation effect, since the heat dissipation holes are open, a large amount of dust will penetrate into the AC residual current monitoring device when it is not in use, which may accelerate the aging rate of the internal components.

[0004] In view of this, an AC residual current monitoring device is provided to overcome the above-mentioned defects. Utility Model Content

[0005] In order to solve the above technical problems, the utility model proposes an AC residual current monitoring device, and its technical solution is: it includes a shell, the front side of the shell is connected to a front cover, the front side of the front cover is inlaid with a display screen, a monitoring element is arranged in the shell, the monitoring element is electrically connected to the display screen, two heat dissipation ports are opened on one side of the shell, a fan is arranged in one of the heat dissipation ports, a mounting frame is fixedly installed in the shell, a threaded screw is rotatably arranged in the mounting frame, a nut is threadedly sleeved on the threaded screw, a sealing piece is connected to one side of the nut, the sealing piece cooperates with the heat dissipation port, and a motor is arranged at the bottom of the mounting frame, and the motor is transmission connected to one end of the threaded screw.

[0006] Furthermore, a connecting piece is fixedly mounted on one side of the nut, and the other end of the connecting piece is fixedly connected to the blocking piece.

[0007] Furthermore, a sliding piece is slidably arranged in the shell, an airbag is arranged in the shell, the airbag abuts against the sliding piece, a contact block and a return spring are arranged at the bottom of the sliding piece, an electromagnetic button is arranged in the shell, the contact block cooperates with and abuts against the electromagnetic button, and the electromagnetic button is electrically connected to the motor.

[0008] Furthermore, a slide rail is provided in the shell, the slide is slidably connected in the slide rail, the airbag is installed in the slide rail, the electromagnetic button is installed on the inner wall of the slide rail, and both ends of the return spring are fixedly connected to the slide and the inner wall of the slide rail respectively.

[0009] Furthermore, a guide rod is inserted into the slide, and both ends of the guide rod are fixedly installed in the slide rail, which can limit the sliding of the slide and avoid the movement deviation problem of the slide.

[0010] Furthermore, filters are fixedly installed in the two heat dissipation ports, which can block external dust when the AC residual current monitoring device is running and dissipating heat, and can further slow down the aging rate of internal components of the AC residual current monitoring device.

[0011] Furthermore, the monitoring element includes a main monitoring unit and a mutual inductor. The main monitoring unit, the mutual inductor and the display screen are electrically connected. The main monitoring unit includes an acquisition chipset, a 485 bus, a CAN communication module, a power supply module, a storage chip and a relay. Through the coordinated monitoring of the main monitoring unit and the mutual inductor, the residual current, switch status and other information under the condition of AC high-resistance grounding can be collected in real time, and the real-time monitoring, alarm, diagnosis, data recording, human-computer interaction and other functions of the insulation status of the AC circuit can be realized, which can greatly improve the efficiency of operation and maintenance and reduce the risk of fire hazards. The reliability of residual current detection is an important condition to ensure the normal operation of the system.

[0012] Furthermore, the four corners of the front side of the front cover are all threadedly inserted with positioning screws, and the ends of the positioning screws pass through the front cover and extend into the shell, so as to facilitate the repair or maintenance of the monitoring element.

[0013] The utility model has the following beneficial effects:

[0014] The AC residual current monitoring device designed by the utility model has an airbag that expands and becomes larger when the temperature inside the shell increases, and at the same time pushes the sliding piece to drive the contact block to abut against the electromagnetic button. At this time, the electromagnetic button turns on the motor, causing the nut to drive the connecting piece and the sealing piece to move downward, so that the two heat dissipation ports can be opened, and then the fan is turned on to discharge the heat inside the shell, thereby achieving the effect of rapid heat dissipation. When the AC residual current monitoring device is not needed, the temperature inside the shell decreases, and similarly the airbag can be reduced in size and the contact block can be separated from the electromagnetic button. At this time, the electromagnetic button reverses the motor drive shaft, so that the sealing piece can abut against the heat dissipation port and seal it, thereby preventing external dust from entering the shell, which helps to extend the service life of the AC residual current monitoring device.

[0015] The AC residual current monitoring device designed in this utility model can collect the residual current, switch status and other information in real time under the condition of AC high-resistance grounding through the coordinated monitoring of the main monitoring unit and the mutual inductor, and realize the real-time monitoring, alarm, diagnosis, data recording, human-computer interaction and other functions of the insulation status of the AC circuit, which can greatly improve the efficiency of operation and maintenance and reduce the risk of fire hazards. The reliability of residual current detection is an important condition to ensure the normal operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the exterior of the utility model;

[0017] Figure 2 It is a three-dimensional structural schematic diagram of the internal half-section of the utility model;

[0018] Figure 3 For this utility model Figure 2 The enlarged view of point A in the middle;

[0019] Figure 4 The circuit diagram of the utility model when it is working;

[0020] Figure 5 It is a flow chart when the utility model is implemented.

[0021] As shown in the figure, 1. Shell; 2. Front cover; 3. Display screen; 4. Monitoring element; 5. Heat dissipation port; 6. Fan; 7. Mounting bracket; 8. Threaded screw; 9. Nut; 10. Sealing piece; 11. Motor; 12. Connector; 13. Slide rail; 14. Slide; 15. Airbag; 16. Contact block; 17. Solenoid button; 18. Reset spring; 19. Guide rod; 20. Filter; 21. Positioning screw. DETAILED DESCRIPTION

[0022] Reference Figure 1-5 The utility model provides an AC residual current monitoring device: comprising a shell 1, a front cover 2 is connected to the front side of the shell 1, a display screen 3 is inlaid on the front side of the front cover 2, a monitoring element 4 is arranged in the shell 1, and the monitoring element 4 is electrically connected to the display screen 3, two heat dissipation ports 5 are provided on one side of the shell 1, a fan 6 is arranged in one of the heat dissipation ports 5, a mounting frame 7 is fixedly installed in the shell 1, a threaded screw 8 is rotatably arranged in the mounting frame 7, a nut 9 is threadedly sleeved on the threaded screw 8, a blocking piece 10 is connected to one side of the nut 9, and the blocking piece 10 is matched with the heat dissipation port 5, a motor 11 is arranged at the bottom of the mounting frame 7, and the motor 11 is drivingly connected to one end of the threaded screw 8;

[0023] A connecting piece 12 is fixedly installed on one side of the nut 9, and the other end of the connecting piece 12 is fixedly connected to the blocking piece 10. A sliding piece 14 is slidably arranged in the shell 1, and an airbag 15 is arranged in the shell 1. The airbag 15 abuts against the sliding piece 14. A contact block 16 and a reset spring 18 are arranged at the bottom of the sliding piece 14. An electromagnetic button 17 is arranged in the shell 1, and the contact block 16 and the electromagnetic button 17 cooperate and abut against each other. The electromagnetic button 17 is electrically connected to the motor 11. A slide rail 13 is opened in the shell 1, and the slide 14 is slidably connected in the slide rail 13. The airbag 15 is installed in the slide rail 13, and the electromagnetic button 17 is installed on the inner wall of the slide rail 13. The two ends of the reset spring 18 are respectively fixedly connected to the slide 14 and the inner wall of the slide rail 13.

[0024] In specific implementation, during the use of the AC residual current monitoring device, the long-term operation of the monitoring element 4 generates more heat. At this time, as the temperature inside the shell 1 becomes higher and higher, the airbag 15 expands and becomes larger due to the increase in temperature. At the same time, the airbag 15 pushes the slide 14 to move downward and compresses the reset spring 18. When the contact block 16 abuts against the electromagnetic button 17, the electromagnetic button 17 sends an electrical signal to the motor 11 to activate it. At this time, the threaded screw 8 rotates, causing the nut 9 to drive the connecting piece 12 and the blocking piece 10 to move downward, and the two The heat dissipation port 5 is opened, and then the fan 6 is turned on, so that the fan 6 discharges the heat inside the shell 1 to achieve the effect of rapid heat dissipation. When the AC residual current monitoring device is not in use, the temperature inside the shell 1 is reduced. Similarly, the airbag 15 can be shrunk, so that the contact block 16 is disengaged from the electromagnetic button 17, so that the electromagnetic button 17 sends an electrical signal to the motor 11 and reverses the drive shaft of the motor 11, so that the blocking member 10 can be abutted against the heat dissipation port 5 and block it, which can prevent external dust from entering the shell 1, and help to extend the service life of the AC residual current monitoring device.

[0025] A guide rod 19 is inserted into the slide 14, and both ends of the guide rod 19 are fixedly mounted in the slide rail 13. The sliding of the slide 14 can be limited to avoid the slide 14 from moving and deviating.

[0026] The two heat dissipation openings 5 ​​are both fixedly installed with filter screens 20. When the AC residual current monitoring device is running and dissipating heat, external dust can be blocked, and the aging rate of the internal components of the AC residual current monitoring device can be further slowed down.

[0027] The monitoring element 4 includes a main monitoring unit and a mutual inductor. The main monitoring unit, the mutual inductor and the display screen 3 are electrically connected. The main monitoring unit includes an acquisition chipset, a 485 bus, a CAN communication module, a power supply module, a storage chip and a relay.

[0028] During specific implementation, the AC power supply equipment to be monitored is electrically connected to the AC residual current monitoring device. Subsequently, through the coordinated monitoring of the main monitoring unit and the transformer, the residual current, switch status and other information under AC high-resistance grounding conditions can be collected in real time, and the real-time monitoring, alarm, diagnosis, data recording, human-computer interaction and other functions of the insulation status of the AC circuit can be realized, which can greatly improve the efficiency of operation and maintenance and reduce the risk of fire hazards. The reliability of residual current detection is an important condition to ensure the normal operation of the system.

[0029] In addition, the detection device is equipped with AC circuit single-phase current collection and residual current calculation technology, and can sample and calculate the A, B, C three-phase currents and the N-phase neutral current in the AC circuit. Under normal circumstances, the vector sum of the three-phase currents is equal to the current flowing through the N line in magnitude and opposite in direction, and they cancel each other out. If the line insulation deteriorates or other reasons cause a phase line to generate a ground current at a certain point, then a current proportional to the residual current will be induced in the coil of the current transformer, and its numerical value reflects the current leakage in the distribution line and electrical equipment. By calculating the size of the residual current, the data is analyzed and processed, and displayed in real time on the monitoring screen or an alarm is given in a timely manner in a fault state, and the data information can be sent to other monitoring devices via the CAN bus or 485 bus;

[0030] The system has perfect monitoring functions and highly intelligent design, which can realize local and remote monitoring of all parameters of each component of the system. The main monitoring quantities are: each phase current of the AC system loop, residual current, switch quantity, etc. The system can automatically detect abnormal residual current in the AC loop and monitor the operating status of the system in real time. The monitoring system is equipped with a standard RS-232 / 485 interface and adopts the standard communication protocol of the Ministry of Electric Power, which is convenient for access to the automation system, provides open protocols, facilitates networking, and simply realizes "four remotes" and unattended operation.

[0031] The main monitoring unit supports 485, 232, and CAN bus communication protocols. The collected data and alarm information of the device can be transmitted to other monitoring units or the background of the integrated power supply in a timely manner, making the integrated power supply monitoring system more complete, the model more reasonable, and the interface between each layer clearer. Advanced digital logic technology is used to complete information collection while realizing intelligent management of information. The AC residual current monitoring device unit has a high degree of functional integration, which reduces the complexity of system design and production on the one hand, and greatly reduces costs on the other.

[0032] As a further implementation of the above technical solution: the four corners of the front side of the front cover 2 are all threaded with positioning screws 21, and the ends of the positioning screws 21 penetrate the front cover 2 and extend into the housing 1. It is convenient to repair or maintain the monitoring element 4.

[0033] Working principle:

[0034] When using the utility model, the AC power supply equipment to be monitored is electrically connected to the AC residual current monitoring device, and then through the coordinated monitoring of the main monitoring unit and the mutual inductor, the residual current, switch status and other information under the AC high-resistance grounding condition can be collected in real time, and the real-time monitoring, alarm, diagnosis, data recording, human-computer interaction and other functions of the insulation status of the AC circuit can be realized, which can greatly improve the efficiency of operation and maintenance and reduce the risk of fire hazards. The reliability of residual current detection is an important condition to ensure the normal operation of the system. In addition, during the use of the AC residual current monitoring device, due to the long-term operation of the monitoring element 4, more heat will be generated. At this time, as the temperature inside the shell 1 becomes higher and higher, the airbag 15 expands and becomes larger due to the increase in temperature. At the same time, the airbag 15 will push the slide 14 to move downward along the direction set by the guide rod 19 and press The reset spring 18 is retracted. When the contact block 16 is against the electromagnetic button 17, the electromagnetic button 17 sends an electrical signal to the motor 11 to activate it. At this time, the threaded screw 8 rotates, so that the nut 9 drives the connecting piece 12 and the blocking piece 10 to move downward, so that the two heat dissipation ports 5 can be opened, and then the fan 6 is turned on to discharge the heat inside the shell 1, thereby achieving a rapid heat dissipation effect. When the AC residual current monitoring device is not needed, the internal temperature of the shell 1 is reduced. Similarly, the airbag 15 can be reduced, so that the contact block 16 is disengaged from the electromagnetic button 17, so that the electromagnetic button 17 sends an electrical signal to the motor 11 and reverses the drive shaft of the motor 11, so that the blocking piece 10 can be against the heat dissipation port 5 and block it, thereby preventing external dust from entering the shell 1, which helps to extend the service life of the AC residual current monitoring device.

[0035] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An AC residual current monitoring device, comprising a housing (1), characterized in that: The front side of the shell (1) is connected to a front cover (2), and a display screen (3) is embedded on the front side of the front cover (2). A monitoring element (4) is arranged in the shell (1), and the monitoring element (4) is electrically connected to the display screen (3). Two heat dissipation ports (5) are provided on one side of the shell (1), and a fan (6) is arranged in one of the heat dissipation ports (5). A mounting frame (7) is fixedly installed in the shell (1), and a threaded screw (8) is rotatably arranged in the mounting frame (7). A nut (9) is threadedly sleeved on the threaded screw (8), and a blocking member (10) is connected to one side of the nut (9), and the blocking member (10) is matched with the heat dissipation port (5) to abut against each other. A motor (11) is arranged at the bottom of the mounting frame (7), and the motor (11) is drivingly connected to one end of the threaded screw (8).

2. The AC residual current monitoring device according to claim 1, characterized in that: A connecting piece (12) is fixedly mounted on one side of the nut (9), and the other end of the connecting piece (12) is fixedly connected to the blocking piece (10).

3. The AC residual current monitoring device according to claim 1, characterized in that: A slide member (14) is slidably arranged in the shell (1), an air bag (15) is arranged in the shell (1), the air bag (15) abuts against the slide member (14), a contact block (16) and a return spring (18) are arranged at the bottom of the slide member (14), an electromagnetic button (17) is arranged in the shell (1), the contact block (16) and the electromagnetic button (17) cooperate and abut against each other, and the electromagnetic button (17) is electrically connected to the motor (11).

4. The AC residual current monitoring device according to claim 3, characterized in that: A slide rail (13) is provided in the housing (1), the slide member (14) is slidably connected in the slide rail (13), the air bag (15) is installed in the slide rail (13), the electromagnetic button (17) is installed on the inner wall of the slide rail (13), and the two ends of the return spring (18) are fixedly connected to the slide member (14) and the inner wall of the slide rail (13), respectively.

5. The AC residual current monitoring device according to claim 4, characterized in that: A guide rod (19) is inserted into the slide member (14), and both ends of the guide rod (19) are fixedly mounted in the slide rail (13).

6. The AC residual current monitoring device according to claim 1, characterized in that: Filter screens (20) are fixedly installed in the two heat dissipation openings (5).

7. The AC residual current monitoring device according to claim 1, characterized in that: The monitoring element (4) comprises a main monitoring unit and a mutual inductor. The main monitoring unit, the mutual inductor and the display screen (3) are electrically connected. The main monitoring unit comprises an acquisition chipset, a 485 bus, a CAN communication module, a power supply module, a storage chip and a relay.

8. The AC residual current monitoring device according to claim 1, characterized in that: The four corners of the front side of the front cover (2) are all threadedly inserted with positioning screws (21), and the ends of the positioning screws (21) penetrate the front cover (2) and extend into the housing (1).

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