An automatic leakage current monitoring device
By integrating an automatic monitoring device with a leakage protection module, automatic monitoring and fault classification early warning of leakage circuit breakers are realized, which solves the problem of timely detection of leakage problems, improves safety and reliability, and avoids the risks caused by human negligence.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHENGZHOU ELECTRIC POWER COLLEGE
- Filing Date
- 2025-08-28
- Publication Date
- 2026-07-31
AI Technical Summary
Existing residual current circuit breakers lack automatic monitoring devices, which makes it impossible to detect leakage problems in time, potentially leading to safety accidents such as electric shock and electrical fires.
An automatic monitoring device integrating a leakage current protection module was designed, including a control circuit board, a motor drive module, a mechanical linkage mechanism, a zero-sequence current transformer, a three-color indicator light, and a mechanical lock mechanism. It realizes automatic monitoring and fault classification early warning. Through current threshold and timed triggering functions, it automatically completes the trip-detection-closing cycle to avoid human oversight.
It achieves automatic monitoring without human intervention, improves the reliability of leakage protection, reduces the risk of electric shock and electrical fire, and eliminates the risk of misoperation through three-color indicator lights and mechanical locking mechanism.
Smart Images
Figure CN224582227U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of air switch technology, and in particular to an automatic leakage current monitoring device. Background Technology
[0002] The intelligent air switch integrates multiple functional modules, including a voltage and current acquisition module, a motor drive module, a mechanical linkage mechanism, a controller, and a communication interface. This integrated design enables the modules to work collaboratively, achieving real-time monitoring and intelligent control of electrical circuits. However, in existing technology, residual current circuit breakers (RCCBs) do not have automatic monitoring devices. They require manual operation by pressing the test button on the RCCB once a month. When the RCCB is powered on, pressing the test button will trip the RCCB and disconnect the power, causing the leakage current indicator to pop up. This indicates that the RCCB is working properly. If the leakage current indicator button can be pressed back down and the circuit can be closed, it can be used normally. If the leakage current indicator does not pop up, it indicates a leakage in the electrical circuit. If the RCCB is not tested manually on a regular basis due to the lack of an automatic monitoring device, or if the leakage current indicator does not pop up during testing and the leakage problem is not investigated, the RCCB may fail or potential leakage problems may go undetected, potentially leading to electric shock, electrical fires, and other safety accidents. Utility Model Content
[0003] The purpose of this invention is to solve the problems existing in the prior art by proposing an automatic leakage current monitoring device.
[0004] To achieve the above objectives, the present invention adopts the following technical solution: an automatic leakage current monitoring device, comprising a housing and a leakage current protection module disposed within the housing, the leakage current protection module integrating an automatic monitoring system, the automatic monitoring system comprising a control circuit board, a motor drive module, a mechanical linkage mechanism, a zero-sequence current transformer, a three-color indicator light, a mechanical lock mechanism, and a voltage and current acquisition module, the control circuit board being installed inside the upper part of the housing and integrating an MCU controller and a communication interface, the voltage and current acquisition module being disposed below the control circuit board, and the motor drive module being fixed to the inner wall of the housing and connected to the control circuit board via a PWM signal line; The mechanical linkage mechanism is installed on the right side of the motor drive module. The mechanical linkage mechanism includes a trip unit and a contact linkage assembly. The zero-sequence current transformer is sleeved on the main circuit output terminal and is electrically connected to the control circuit board. The three-color indicator light is embedded on the upper front of the housing. The three-color indicator light includes a red fault light, a yellow warning light, and a green running light, which are electrically connected to the control circuit board respectively. The mechanical lock mechanism is installed below the operating handle. The mechanical lock mechanism includes a locking rod and a drive electromagnet. The locking rod and the operating handle are in a vertical limiting relationship.
[0005] Preferably, a leakage current indicator pop-up mechanism is installed at the end of the mechanical linkage mechanism. The leakage current indicator pop-up mechanism is located in the center of the front of the housing and is triggered synchronously with the tripping action of the operating handle.
[0006] Preferably, the control circuit board has a built-in current threshold trigger unit and a timing trigger unit. The current threshold trigger unit receives the real-time current signal from the voltage and current acquisition module. The current threshold trigger unit and the timing trigger unit control the motor drive module to operate. The timing trigger unit triggers the motor drive module to operate on a cycle of 15-90 days.
[0007] Preferably, the locking rod of the mechanical lock mechanism cooperates with the limiting groove of the operating handle. When the control circuit board detects a fault in an internal component, it drives the electromagnet to move the locking rod into the limiting groove and lock the operating handle.
[0008] Preferably, the zero-sequence current transformer is connected to the control circuit board via a shielded cable, and a metal shield is installed on the outside of the motor drive module, with a grounding resistance ≤1Ω.
[0009] Preferably, a test button is mounted on the surface of the housing.
[0010] Compared with the prior art, the advantages and positive effects of this utility model are as follows: 1. This utility model integrates a voltage and current acquisition module, a control circuit board, and a motor drive module to achieve automatic monitoring without human intervention, replacing the traditional manual operation of pressing the test button monthly. When the line current reaches a preset threshold or is triggered by a timed cycle, the control circuit board drives the motor to activate the mechanical linkage mechanism to complete the trip-detection-closing cycle. The zero-sequence current transformer simultaneously verifies the effectiveness of the protection function, avoiding protection failures due to human error and improving monitoring reliability.
[0011] 2. In this utility model, a fault classification early warning and misoperation protection system is constructed through the linkage design of the three-color indicator light and the mechanical lock mechanism. When a circuit leakage is detected, the leakage indicator pops up and the yellow warning light illuminates, and the mechanical lock semi-locks the operating handle to prevent accidental closing. If internal components are damaged, the red fault light remains on and the mechanical lock is forcibly locked. Through the vertical limiting structure of the locking rod and the operating handle limit groove, the circuit is forcibly disconnected, eliminating the hidden danger of "false normality" and effectively reducing the risk of electric shock and electrical fire. Attached Figure Description
[0012] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 This is a flowchart illustrating the present invention.
[0013] Legend: 1. Housing; 2. Three-color indicator light; 3. Test button; 4. Operating handle; 5. Mechanical lock mechanism; 6. Control circuit board; 7. Voltage and current acquisition module; 8. Motor drive module; 9. Mechanical linkage mechanism; 10. Zero-sequence current transformer; 11. Leakage indicator pop-up mechanism. Detailed Implementation
[0014] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.
[0015] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.
[0016] Example 1: As Figures 1-3 As shown, this utility model provides an automatic leakage current monitoring device, including a housing 1 and a leakage current protection module disposed inside the housing 1. The leakage current protection module integrates an automatic monitoring system. The automatic monitoring system includes a control circuit board 6, a motor drive module 8, a mechanical linkage mechanism 9, a zero-sequence current transformer 10, a three-color indicator light 2, a mechanical lock mechanism 5, and a voltage and current acquisition module 7. The control circuit board 6 is installed inside the upper part of the housing 1 and integrates an MCU controller and a communication interface. The voltage and current acquisition module 7 is disposed below the control circuit board 6. The motor drive module 8 is fixed to the inner wall of the housing 1 and is connected to the control circuit board 6 through a PWM signal line. The mechanical linkage mechanism 9 is installed on the right side of the motor drive module 8. The mechanical linkage mechanism 9 includes a trip unit and a contact linkage assembly. The zero-sequence current transformer 10 is sleeved on the main circuit output terminal and is electrically connected to the control circuit board 6. The three-color indicator light 2 is embedded on the upper front of the housing 1. The three-color indicator light 2 includes a red fault light, a yellow warning light, and a green running light, which are electrically connected to the control circuit board 6 respectively. The mechanical lock mechanism 5 is installed below the operating handle 4. The mechanical lock mechanism 5 includes a locking rod and a driving electromagnet. The locking rod and the operating handle 4 are in a vertical limiting relationship. The zero-sequence current transformer 10 is connected to the control circuit board 6 through a shielded cable. A metal shield is set on the outside of the motor drive module 8. The grounding resistance is ≤1Ω. A test button 3 is installed on the surface of the housing 1.
[0017] The specific settings and functions of this embodiment are described below. The outer shell 1 is made of ABS engineering plastic with a thickness of 3mm. A three-color indicator light 2 is embedded in the upper front, a leakage current indicator pop-up mechanism 11 is set in the middle, and an operating handle 4 and a mechanical lock mechanism 5 are located below. A test button 3 is exposed on the right side.
[0018] The control circuit board 6 is fixed to the upper inner wall of the housing 1 with screws. It integrates an STM32F103 chip and an RS485 communication interface. The voltage and current acquisition module 7 is installed parallel below it and is connected to the live and neutral wires of the main circuit through shielded cables. The acquisition accuracy is ±0.5%FS. The motor drive module 8 is fixed to the inner left side of the housing 1. It adopts a DC12V stepper motor driver and is connected to the control circuit board 6 through a PWM signal line. The output shaft extends to the right to the mechanical linkage mechanism 9. The mechanical linkage mechanism 9 includes a metal trip unit and a spring contact assembly. The left end is connected to the output shaft of the motor drive module 8 by a key, and the right end is linked to the leakage current indicator pop-out mechanism 11. When the trip unit is activated, the leakage current indicator pop-out mechanism 11 pops forward 5mm.
[0019] The zero-sequence current transformer 10 is installed at the main circuit output terminal with a rated current of 32A. It is located in the middle of the housing 1 and transmits the leakage signal to the control circuit board 6 through the shielded cable. The grounding resistance of the shielding layer is 0.8Ω. The mechanical locking mechanism 5 is installed directly below the operating handle 4. The driving electromagnet 13 is fixed to the bottom plate of the housing through the bracket. The locking rod 12 is vertically upward and aligned with the limit groove 14 at the bottom of the operating handle 4. Under normal conditions, the distance between the locking rod and the limit groove is 2mm.
[0020] When the control circuit board 6 detects that the line current exceeds the preset threshold (e.g., 25A) for 100ms via the voltage and current acquisition module 7, the current threshold trigger unit outputs a high-level signal to the motor drive module 8. The motor drive module 8 drives the stepper motor to rotate, causing the mechanical linkage mechanism 9 to trip. The operating handle 4 jumps to the "OFF" position, and at the same time, the leakage current indicator pop-up mechanism 11 pops out, the yellow warning light illuminates, and the zero-sequence current transformer 10 detects the leakage current signal during tripping. If the signal is normal and there is no actual leakage current, the control circuit board 6 drives the motor to reverse after 500ms, the mechanical linkage mechanism 9 resets and closes, the green running light stays on, and the leakage current indicator pop-up mechanism 11 retracts. If the zero-sequence current transformer 10 does not detect the expected signal after tripping, such as due to internal component damage, the control circuit board 6 drives the electromagnet 13 of the mechanical lock mechanism 5 to engage, the locking rod 12 inserts into the limit slot 14, locks the operating handle 4, and the red fault light stays on.
[0021] Example 2: Figure 1 and Figure 2As shown, a leakage current indicator pop-up mechanism 11 is installed at the end of the mechanical linkage mechanism 9. The leakage current indicator pop-up mechanism 11 is located in the center of the front of the housing and is triggered synchronously with the tripping action of the operating handle 4. The control circuit board 6 has a built-in current threshold trigger unit and a timer trigger unit. The current threshold trigger unit receives the real-time current signal from the voltage and current acquisition module 7. The current threshold trigger unit and the timer trigger unit control the motor drive module 8 to operate. The timer trigger unit triggers the motor drive module 8 to operate according to a 15-90 day cycle. The locking rod of the mechanical lock mechanism 5 cooperates with the limit groove of the operating handle 4. When the control circuit board 6 detects a fault in the internal components, it drives the electromagnet to drive the locking rod to insert into the limit groove and lock the operating handle 4.
[0022] The overall implementation achieves the following effects: the control circuit board 6 has a built-in timer module, which is configured by the host computer to have a timing period of 30 days, and performs automatic testing at 2:00 AM every day; the current threshold trigger unit has a preset threshold of 50A; a 0.5mm thick metal shield is added to the outside of the motor drive module 8, and the grounding terminal is connected to the grounding post of the outer shell 1 through a wire with a grounding resistance of 0.5Ω to avoid electromagnetic interference; the zero-sequence current transformer 10 is a 1000:1 model, which is installed at the output terminal of the three-phase four-wire main circuit; the signal cable is a twisted pair shielded cable, and a 10nF filter capacitor is connected in parallel with the input terminal of the control circuit board 6.
[0023] The locking rod 12 of the mechanical lock mechanism 5 is designed to be 15mm long and can withstand 18N of operating resistance after being inserted into the limit slot 14. The yellow warning light adopts a flashing mode of 1 time / second. When the circuit leaks electricity, it flashes continuously until the fault is cleared. At 2:00 a.m. on the preset time period of 30 days, the timer trigger unit of the control circuit board 6 is activated and sends a pulse signal to the motor drive module 8.
[0024] The motor drive module 8 drives the mechanical linkage mechanism 9 to perform a trip action, the leakage current indicator pop-up mechanism 11 pops up, and the yellow warning light illuminates; at the same time, the zero-sequence current transformer 10 detects the leakage current signal. If the trip response is normal, the leakage current indicator pops up and the transformer signal is normal, the control circuit board 6 closes the circuit after 500ms, the green running light stays on, and the leakage current indicator pop-up mechanism 11 resets; if the leakage current indicator does not pop up after the trip, it is determined to be an internal component failure, the red fault light stays on, and the mechanical lock mechanism 5 locks the operating handle 4.
[0025] This device was installed in a lighting circuit of a shopping mall, with a timing cycle set to 30 days. During testing, the connection between the zero-sequence current transformer 10 and the control circuit board 6 was manually disconnected to simulate a transformer failure. After the timing test was triggered, the device tripped, but the leakage current indicator did not pop up. The control circuit board 6 detected the abnormal signal and immediately activated the mechanical lock mechanism 5 to lock the operating handle 4. The red fault light remained on. At this time, the manual operating handle 4 could not be closed until the transformer connection was repaired and the mechanical lock unlock button 5 was pressed with a special tool to unlock it.
[0026] The above are merely preferred embodiments of this utility model and are not intended to limit the utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from the technical solution of this utility model shall still fall within the protection scope of this utility model.
Claims
1. An electric leakage automatic monitoring device, comprising a shell (1) and an electric leakage protection module arranged in the shell (1), characterized in that: The leakage protection module integrates an automatic monitoring system, which includes a control circuit board (6), a motor drive module (8), a mechanical linkage mechanism (9), a zero-sequence current transformer (10), a three-color indicator light (2), a mechanical lock mechanism (5), and a voltage and current acquisition module (7). The control circuit board (6) is installed inside the upper part of the housing (1) and integrates an MCU controller and a communication interface. The voltage and current acquisition module (7) is located below the control circuit board (6). The motor drive module (8) is fixed to the inner wall of the housing (1) and is connected to the control circuit board (6) through a PWM signal line. The mechanical linkage mechanism (9) is installed on the right side of the motor drive module (8). The mechanical linkage mechanism (9) includes a trip unit and a contact linkage assembly. The zero-sequence current transformer (10) is sleeved on the main circuit output terminal. The zero-sequence current transformer (10) is electrically connected to the control circuit board (6). The three-color indicator light (2) is embedded on the front top of the housing (1). The three-color indicator light (2) includes a red fault light, a yellow warning light, and a green running light, which are electrically connected to the control circuit board (6) respectively. The mechanical lock mechanism (5) is installed below the operating handle (4). The mechanical lock mechanism (5) includes a locking rod and a driving electromagnet. The locking rod and the operating handle (4) are in a vertical limiting relationship.
2. The electric leakage automatic monitoring device according to claim 1, characterized in that: The mechanical linkage mechanism (9) is equipped with a leakage current indicator pop-out mechanism (11). The leakage current indicator pop-out mechanism (11) is located in the middle of the front of the housing and is triggered synchronously with the tripping action of the operating handle (4).
3. The automatic leakage current monitoring device according to claim 1, characterized in that: The control circuit board (6) has a built-in current threshold trigger unit and a timing trigger unit. The current threshold trigger unit receives the real-time current signal from the voltage and current acquisition module (7). The current threshold trigger unit and the timing trigger unit control the motor drive module (8) to operate. The timing trigger unit triggers the motor drive module (8) to operate according to a 15-90 day cycle.
4. The automatic leakage current monitoring device according to claim 1, characterized in that: The locking rod of the mechanical lock mechanism (5) cooperates with the limiting groove of the operating handle (4). When the control circuit board (6) detects a fault in the internal components, it drives the electromagnet to insert the locking rod into the limiting groove and lock the operating handle (4).
5. The automatic leakage current monitoring device according to claim 1, characterized in that: The zero-sequence current transformer (10) is connected to the control circuit board (6) by a shielded cable. The motor drive module (8) is equipped with a metal shield and the grounding resistance is ≤1Ω.
6. The automatic leakage current monitoring device according to claim 1, characterized in that: A test button (3) is installed on the surface of the outer casing (1).