A control circuit for a leakage protection switch device with automatic reset and self-checking function

Abstract

The present invention discloses a control circuit for an automatic reset and self-checking leakage protection switch device, comprising a power supply end, an output end and an MCU control circuit. A live wire, a neutral wire and a ground wire between the power supply end and the output end are connected to a switch that can automatically reset and energize after being attracted by a coil. The MCU control circuit is connected to a power supply anti-shake detection circuit and a coil high-current attraction circuit for outputting a large current to energize the coil and attract the switch. The power supply end is connected to a coil low-current attraction circuit for outputting a small current to maintain the coil energized and attracted. The coil is connected to an LN line leakage and self-checking control circuit for respectively detecting faults of the coil, a thyristor, a detection chip and a current transformer. The LN line leakage and self-checking control circuit is connected to a self-checking fault alarm circuit for fault alarm prompts. The present invention realizes automatic resetting and energization after power failure, manual resetting before energization after pressing a test switch or after leakage, and alarm after automatic fault detection at regular intervals, thereby avoiding accidents.

Description

[Technical field]

[0001] The invention relates to a control circuit of an electric leakage protection switch device which automatically resets and has a self-checking function. [Background Technology]

[0002] The leakage protection switch devices currently on the domestic market, such as leakage protection plugs, generally have the following defects:

[0003] 1. After the input power is disconnected, the switch of the control circuit cannot be automatically disconnected and remains in the connected state.

[0004] 2. When the key components of the control circuit are damaged, the leakage protection function of the control circuit will fail, which may easily cause leakage accidents.

[0005] 3. When the user presses the test switch or reconnects the input power after a leakage accident occurs, the switch is still in the connected state, causing the switch to connect to the power supply, causing damage to the load electrical appliances and leading to a safety accident.

[0006] 4. When the leakage protection plug is in poor contact with the socket, the voltage waveform of the input power supply is not a sine wave, which will also damage the load electrical appliances and shorten the service life of the load electrical appliances.

[0007] 5. The standby power of the leakage protection plug is high, which consumes too much electricity and is not in line with the concept of green and environmentally friendly electricity use.

[0008] 6. The control circuit and structure of the leakage protection plug are complex, the production efficiency is low, the product cost is high, and it is not conducive to market promotion. [Summary of the invention]

[0009] The present invention overcomes the deficiencies of the above-mentioned technologies and provides a control circuit for a leakage protection switch device which is automatically reset and has a self-checking function.

[0010] The technical solution adopted by the present invention to solve its technical problem is:

[0011] A control circuit for an earth leakage protection switch device with automatic reset and self-checking function, characterized in that it includes a power supply terminal 1 connected to an input power supply, an output terminal 4 connected to a load, and an MCU control circuit 6, wherein the live wire, the neutral wire, and the ground wire between the power supply terminal 1 and the output terminal 4 are connected to a switch 2 that can automatically reset and energize after being attracted by a coil 3, and the MCU control circuit 6 is connected to a power supply anti-shake detection circuit 5 for detecting the positive and negative periodic voltage waveforms of the input power supply, and a circuit for outputting a large current when the power supply anti-shake detection circuit 5 detects that the input power supply voltage waveform is a sine wave within a preset time. The coil 3 is energized to attract the coil high-current attraction circuit 7 of the switch 2. The power supply end 1 is connected to the coil low-current attraction circuit 8 that maintains the coil 3 energized and attracted after the coil 3 attracts the switch 2. The coil 3 is connected to the LN line leakage and self-detection control circuit 11 that performs fault detection on the coil 3 and the thyristor 22 respectively and performs fault self-detection on the detection chip U1 and the current transformer ZCT1. The LN line leakage and self-detection control circuit 11 is connected to the self-detection fault alarm circuit 21 that alarms when the LN line leakage and self-detection control circuit 11 detects a fault.

[0012] The control circuit of the leakage protection switch device with automatic reset and self-test function as described above is characterized in that the MCU control circuit 6 is also connected to an MCU leakage signal detection circuit 10, and the MCU leakage signal detection circuit 10 is connected to an LN line leakage and self-test control circuit 11 for detecting the live wire or neutral wire leakage signal of the output terminal 4 and a PE line fault current detection control circuit 12 for detecting the ground wire leakage signal of the output terminal 4. When the LN line leakage and self-test control circuit 11 or the PE line fault current detection control circuit 12 detects a leakage signal, the MCU leakage signal detection circuit 10 outputs the leakage signal to the MCU control circuit 6 and controls the thyristor 22 to be turned on, so that the coil 3 is de-energized and the switch 2 is not attracted.

[0013] The control circuit of the leakage protection switch device with automatic reset and self-test function as described above is characterized in that the MCU control circuit 6 is connected to an over-temperature detection circuit 17 for detecting the temperature of the live wire or neutral wire pin, and an over-temperature protection control circuit 9 for outputting an analog leakage signal when the pin temperature exceeds a set temperature; the live wire of the output end 4 is connected to a TEST simulated leakage circuit 15 for outputting an analog leakage signal for manual testing; when the LN line leakage and self-test control circuit 11 detects the simulated leakage signal of the over-temperature protection control circuit 9 or the TEST simulated leakage circuit 15, the MCU leakage signal detection circuit 10 outputs the simulated leakage signal to the MCU control circuit 6 and controls the thyristor 22 to be turned on, so that the coil 3 is de-energized and the switch 2 is not attracted.

[0014] The control circuit of the leakage protection switch device with automatic reset and self-test function as described above is characterized in that a grounding abnormality prompt circuit 13 that illuminates when the ground wire is energized is connected between the neutral wire and the ground wire of the power supply terminal 1, a power indicator circuit 14 that illuminates when the live wire of the output terminal 4 is energized is connected between the live wire of the output terminal 4 and the neutral wire of the power supply terminal 1, the MCU control circuit 6 is powered by an MCU control power supply RC step-down circuit 16, the MCU control circuit 6 is connected to a power-on reset circuit 18 for manual reset, a TEST and leakage alarm indication circuit 19 that illuminates when leakage occurs, and the LN line leakage and self-test control circuit 11 and the PE line fault current detection control circuit 12 are powered by a leakage control power supply RC step-down circuit 20.

[0015] The control circuit of the leakage protection switch device with automatic reset and self-test function as described above is characterized in that the power supply anti-shake detection circuit 5 includes a transistor Q2, the emitter of the transistor Q2 is electrically connected to the neutral line of the power supply terminal 1, the base of the transistor Q2 is electrically connected to one end of the resistor R34 and one end of the resistor R35, the other end of the resistor R35 is electrically connected to one end of the resistor R36, the other end of the resistor R36 is electrically connected to the live wire of the power supply terminal 1, the other end of the resistor R34 is electrically connected to the neutral line of the power supply terminal 1, and the collector of the transistor Q2 is electrically connected to pin P00 of the MCU control circuit 6.

[0016] The control circuit of the leakage protection switch device with automatic reset and self-test function as described above is characterized in that the coil high current pickup circuit 7 includes a control chip U2, the pin LED+ of the control chip U2 is electrically connected to one end of the resistor R7, the other end of the resistor R7 is electrically connected to the pin P01 of the MCU control circuit 6, the pin LED- of the control chip U2 is electrically connected to the neutral line of the power supply terminal 1, the pin Terminal1 of the control chip U2 is electrically connected to one end of the coil 3, the pin Terminal2 of the control chip U2 is electrically connected to the negative electrode of the diode D9, the positive electrode of the diode D9 is electrically connected to one end of the resistor R3, the other end of the resistor R3 is electrically connected to the live wire of the power supply terminal 1, and the other end of the coil 3 is electrically connected to the neutral line of the power supply terminal 1.

[0017] The control circuit of the leakage protection switch device with automatic reset and self-test function as described above is characterized in that the small current pickup circuit 8 includes a resistor R1A, one end of the resistor R1A is electrically connected to one end of the resistor R1B, the other end of the resistor R1B is electrically connected to one end of the capacitor C1 and the live wire of the power supply terminal 1, the other end of the resistor R1A is electrically connected to the other end of the capacitor C1, the negative electrode of the diode D5, and the positive electrode of the diode D7, the positive electrode of the diode D5 is electrically connected to the neutral wire of the power supply terminal 1, the negative electrode of the polarity capacitor C6, and one end of the coil 3, and the negative electrode of the diode D7 is electrically connected to the positive electrode of the polarity capacitor C6 and the other end of the coil 3.

[0018] The above-mentioned automatic reset and self-test function leakage protection switch device control circuit is characterized in that the MCU leakage signal detection circuit 10 includes a transistor Q4, the collector of the transistor Q4 is electrically connected to one end of the resistor R8 and the pin P02 of the MCU control circuit 6, the other end of the resistor R8 is electrically connected to the pin VDD of the MCU control circuit 6, the emitter of the transistor Q4 is electrically connected to one end of the capacitor C8 and the neutral line of the power supply terminal 1, the base of the transistor Q4 is electrically connected to the other end of the capacitor C8 and one end of the resistor R9, and the other end of the resistor R9 is electrically connected to the VDD pin of the MCU control circuit 6. One end of the resistor R10 is electrically connected to the output end of the dual-way switching diode Q3, one input end of the dual-way switching diode Q3 is electrically connected to the resistor R19, the resistor R19 is electrically connected to the pin TRIG of the detection chip U1, the other input end of the dual-way switching diode Q3 is electrically connected to the pin SCR of the detection chip U1E, the other end of the resistor R10 is electrically connected to one end of the capacitor C9 and the control electrode of the thyristor 22, the other end of the capacitor C9 is electrically connected to the neutral line of the power supply terminal 1 and the negative electrode of the thyristor 22, and the positive electrode of the thyristor 22 is electrically connected to one end of the coil 3.

[0019] The above-mentioned automatic reset and self-test function leakage protection switch device control circuit is characterized in that the LN line leakage and self-test control circuit 11 includes a detection chip U1, the pin VDDRC of the detection chip U1 is electrically connected to the pin VDD of the MCU control circuit 6 and one end of the capacitor C17, the pin STP of the detection chip U1 is electrically connected to the other end of the capacitor C17 and one end of the resistor R22, the other end of the resistor R22 is electrically connected to the collector of the transistor Q6, the emitter of the transistor Q6 is electrically connected to the neutral line of the power supply 1, the pin CFRC of the detection chip U1 is electrically connected to one end of the capacitor C16, and the other end of the capacitor C16 is electrically connected to the neutral line of the power supply 1. The pin TRIG of the detection chip U1 is electrically connected to one end of the resistor R19 and the cathode of the diode D12. The pin FOUT of the detection chip U1 is electrically connected to the anode of the diode D12, one end of the resistor R20, and one input end of the dual-way switch diode Q5. The other end of the resistor R20 is electrically connected to the base of the transistor Q6. The other input end of the dual-way switch diode Q5 is electrically connected to the pin P05 of the MCU control circuit 6. The output end of the dual-way switch diode Q5 is electrically connected to one end of the resistor R21. The pin EOL of the detection chip U1 is electrically connected to one end of the resistor R27. The other end of the resistor R27 is electrically connected to the anode of the light-emitting diode D13. The cathode of the light-emitting diode D13 is electrically connected to the neutral line of the power supply terminal 1, the pin VDDST of the detection chip U1 is electrically connected to one end of the resistor R6 and one end of the capacitor C10, and the other end of the capacitor C10 is electrically connected to the neutral line of the power supply terminal 1, the pin STIN of the detection chip U1 is electrically connected to one end of the resistor R26 and the positive electrode of the diode D14, and the other end of the resistor R26 is electrically connected to the negative electrode of the diode D14, one end of the coil 3, and the positive electrode of the thyristor 22, the pin GNDST of the detection chip U1 is electrically connected to the pin GNDRC of the detection chip U1 and the neutral line of the power supply terminal 1, and the pin RCT2 of the detection chip U1 is electrically connected to one end of the capacitor C18. , one end of the resistor R25 is electrically connected, the other end of the resistor R25 is electrically connected to one end of the resistor R23 and one end of the current transformer ZCT1, the other end of the current transformer ZCT1 is electrically connected to the other end of the resistor R23 and one end of the resistor R24, the other end of the resistor R24 is electrically connected to the other end of the capacitor C18 and the pin RCT1 of the detection chip U1, the live wire and the neutral wire of the output terminal 4, the connecting line between the emitter of the transistor Q1 of the over-temperature protection control circuit 9 and the neutral wire of the power supply terminal 1, and the connecting line between the test switch TEST of the TEST simulated leakage circuit 15 and the live wire of the output terminal 4 all pass through the center of the current transformer ZCT1.The PE line fault current detection control circuit 12 includes a detection chip U1E, wherein the pin Neutral of the detection chip U1E is electrically connected to one end of the capacitor C13 and the neutral line of the power supply terminal 1, the pin Line of the detection chip U1E is electrically connected to one end of the resistor R6 and one end of the capacitor C10, the pin VREF of the detection chip U1E is electrically connected to the other end of the capacitor C13, one end of the capacitor C14, one end of the resistor R29, and one end of the current transformer ZCT2, the other end of the current transformer ZCT2 is electrically connected to the other end of the resistor R29, the other end of the capacitor C14, and one end of the resistor R30, the other end of the resistor R30 is electrically connected to one end of the capacitor C15, one end of the resistor R28, and the pin VFB of the detection chip U1E, the pin AmpOUT of the detection chip U1E is electrically connected to the other end of the capacitor C15 and the other end of the resistor R28, and the ground wire of the output terminal 4 passes through the center of the current transformer ZCT2.

[0020] The above-mentioned automatic reset and self-test function leakage protection switch device control circuit is characterized in that the over-temperature detection circuit 17 includes a thermistor R13, one end of the thermistor R13 is electrically connected to the neutral line of the power supply terminal 1 and one end of the capacitor C5, the other end of the thermistor R13 is electrically connected to one end of the resistor R14 and one end of the resistor R15, the other end of the resistor R14 is electrically connected to the pin VDD of the MCU control circuit 6, the other end of the resistor R15 is electrically connected to the pin P03 of the MCU control circuit 6 and the other end of the capacitor C5, the over-temperature protection control circuit 9 includes a transistor Q1, the collector of the transistor Q1 is electrically connected to one end of the resistor R33B, and the resistor R The other end of 33B is electrically connected to one end of the resistor R33A, the other end of the resistor R33A is electrically connected to the cathode of the diode D8, the anode of the diode D8 is electrically connected to the live wire of the power supply terminal 1, the emitter of the transistor Q1 is electrically connected to the neutral wire of the power supply terminal 1, the base of the transistor Q1 is electrically connected to one end of the resistor R21, the TEST simulated leakage circuit 15 includes a test switch TEST, one end of the test switch TEST is electrically connected to the live wire of the output terminal 4, the other end of the test switch TEST is electrically connected to one end of the resistor R32B, the other end of the resistor R32B is electrically connected to one end of the resistor R32A, and the other end of the resistor R32A is electrically connected to the neutral wire of the power supply terminal 1.

[0021] The beneficial effects of the present invention are:

[0022] 1. After the present invention is powered on, the positive and negative periodic voltage waveforms of the input power supply are first detected. When the input power supply voltage waveform is a sine wave, the control circuit closes the switch to connect the power supply, and the load electrical appliance connected to the output end is energized and works; when the input power is disconnected, the switch of the control circuit can be automatically disconnected.

[0023] 2. When the input power is disconnected and then powered on, the control circuit can be automatically reset without manual operation.

[0024] 3. The present invention can automatically detect whether the functions of the coil, thyristor, detection chip, and current transformer fail at regular intervals. When the functions of the coil, thyristor, detection chip, and current transformer fail, a fault alarm prompt can be issued to the user in a timely manner, reminding the user to manually disconnect the power supply, replace the leakage protection switch device in time, check for safety hazards, and avoid major safety accidents.

[0025] 4. When the user actively presses the test switch or a leakage accident occurs, the input power can be immediately disconnected and an alarm prompt is issued. The reset switch must be manually pressed to reset the power.

[0026] 5. When the voltage waveform of the input power supply is not a sine wave, for example, the leakage protection plug is in poor contact with the socket, the control circuit can actively disconnect the power supply to avoid damage to the load electrical appliances and extend the service life of the load electrical appliances.

[0027] 6. When the temperature of the live or neutral wire pin exceeds the set temperature, the control circuit can actively disconnect the input power. When the pin temperature drops below the set temperature, the control circuit can automatically connect the power.

[0028] 7. The power supply of the control circuit adopts a resistance-capacitance step-down circuit, which can reduce the heat generated during operation and the power loss during standby, which is green and environmentally friendly.

[0029] 8. The present invention has a simple structure, is easy to implement, has good practicality, and can greatly improve safety in use. [Brief Description of the Drawings]

[0030] Figure 1 is a control circuit logic diagram of the present invention;

[0031] Figure 2 This is a schematic diagram of the control circuit of the present invention. [Specific implementation method]

[0032] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings:

[0033] like Figure 1-2As shown, a control circuit for an automatic reset and self-testing leakage protection switch device is characterized in that it includes a power supply terminal 1 connected to an input power supply, an output terminal 4 connected to a load, and an MCU control circuit 6. The live wire, neutral wire, and ground wire between the power supply terminal 1 and the output terminal 4 are connected to a switch 2 that can automatically reset and energize after being attracted by a coil 3. The MCU control circuit 6 is connected to a power supply anti-shake detection circuit 5 for detecting the positive and negative periodic voltage waveforms of the input power supply, and is used for the power supply anti-shake detection circuit 5 to output a large current when it detects that the input power supply voltage waveform is a sine wave within a preset time. A high-current coil pickup circuit 7 is provided for energizing the coil 3 and closing the switch 2. The power supply end 1 is connected to a low-current coil pickup circuit 8 for maintaining the coil 3 energized and closed after the coil 3 closes the switch 2. The coil 3 is connected to an LN line leakage and self-detection control circuit 11 for respectively detecting faults of the coil 3 and the thyristor 22 and performing self-detection of faults on the detection chip U1 and the current transformer ZCT1. The LN line leakage and self-detection control circuit 11 is connected to a self-detection fault alarm circuit 21 for issuing an alarm when the LN line leakage and self-detection control circuit 11 detects a fault.

[0034] When power is first applied, the power supply anti-shake detection circuit 5 processes the input power voltage waveform and outputs the processed input power voltage waveform to the MCU control circuit 6. Within a preset time of 2 seconds, if the voltage waveform is a sine wave, the MCU control circuit 6 outputs a high level to the coil high-current pickup circuit 7. The high level lasts for less than 50 milliseconds, driving the coil high-current pickup circuit 7 to output a high current, energizing the coil 3 and attracting the switch 2. The low-current pickup circuit 8 can output a low current to the coil 3, maintaining the coil 3 energized and attracting the switch 2, causing the switch 2 to reset and power on. When the input power is disconnected, the entire control circuit shuts down, the coil 3 loses current, and the switch 2 stops being attracted, turning it off. When power is applied again, the control circuit repeats the above process, thus achieving the function of automatically disconnecting the switch after disconnecting the input power and automatically resetting and powering it on when the input power is reconnected, without manual operation. If the input power voltage waveform is not a sine wave, such as when the leakage protection plug is in poor contact with the socket, the control circuit actively disconnects the power supply, preventing damage to the load electrical equipment and extending the service life of the load electrical equipment. The above-mentioned preset time of 2 seconds and high-level duration of 50 milliseconds are values of an embodiment of this case, and the preset time and high-level duration can be set to other values according to actual applications.

[0035] When the LN line leakage and self-test control circuit 11 is powered on for the first time, it starts self-testing after a first self-test delay time of 2 seconds. The voltage cycle of the input power supply is used as the power frequency cycle, and the pin FOUT of the detection chip U1 outputs an analog fault excitation signal in the negative half power frequency cycle. When the positive half power frequency cycle of the input signal of the pin STIN of the detection chip U1 is a high level and the negative half power frequency cycle is a low level, the self-test module of the detection chip U1 determines that the functions of the coil 3, the thyristor 22, the leakage protection module of the detection chip U1, and the current transformer ZCT1 are all normal. Then the self-test module of the detection chip U1 performs the above self-test process once every 11 minutes of the regular self-test cycle. During the initial self-test or regular cycle self-test, if the input signal at pin STIN of detection chip U1 remains high or low, the self-test module of detection chip U1 will perform three consecutive repeated self-tests within the next three power frequency cycles. If the input signal at pin STIN of detection chip U1 remains high or low, the self-test module of detection chip U1 will determine that one of coil 3, thyristor 22, leakage protection module of detection chip U1, or current transformer ZCT1 is damaged. At this time, pin EOL of detection chip U1 will output a fault alarm signal, driving self-test fault alarm circuit 21 to illuminate and issue an alarm. The aforementioned 2-second initial self-test delay, 11-minute regular self-test cycle, 3 power frequency cycles, and 3 repeated self-tests are values for one embodiment of this case, and the initial self-test delay, regular self-test cycle, number of power frequency cycles for repeated self-test, and number of repeated self-tests can be set to other values based on actual application.

[0036] like Figure 1-2 As shown, the MCU control circuit 6 is further connected to an MCU leakage signal detection circuit 10. The MCU leakage signal detection circuit 10 is connected to an LN line leakage and self-test control circuit 11 for detecting live or neutral line leakage signals at the output terminal 4, and a PE line fault current detection control circuit 12 for detecting ground line leakage signals at the output terminal 4. When the LN line leakage and self-test control circuit 11 or the PE line fault current detection control circuit 12 detects a leakage signal, the MCU leakage signal detection circuit 10 outputs the leakage signal to the MCU control circuit 6 and controls the thyristor 22 to conduct, thereby de-energizing the coil 3 and preventing the switch 2 from being attracted. When no leakage occurs, neither the LN line leakage and self-test control circuit 11 nor the PE line fault current detection control circuit 12 detects a leakage signal, and the MCU leakage signal detection circuit 10 does not output a leakage signal to the MCU control circuit 6. The MCU leakage signal detection circuit 10 controls the thyristor 22 to be turned off, maintaining the coil 3 energized and attracting the switch 2.

[0037] like Figure 1-2As shown, the MCU control circuit 6 is connected to an over-temperature detection circuit 17 for detecting the temperature of the live or neutral pins, and an over-temperature protection control circuit 9 for outputting a simulated leakage signal when the pin temperature exceeds a set temperature. The live wire of the output terminal 4 is connected to a TEST simulated leakage circuit 15 for outputting a simulated leakage signal during manual testing. When the LN line leakage and self-test control circuit 11 detects a simulated leakage signal from the over-temperature protection control circuit 9 or the TEST simulated leakage circuit 15, the MCU leakage signal detection circuit 10 outputs the simulated leakage signal to the MCU control circuit 6 and controls the thyristor 22 to conduct, de-energizing the coil 3 and preventing the switch 2 from being engaged. When the pin temperature is below the set temperature or the user does not press the test switch TEST, the over-temperature protection control circuit 9 and the TEST simulated leakage circuit 15 do not output the simulated leakage signal, and the MCU leakage signal detection circuit 10 does not output the simulated leakage signal to the MCU control circuit 6. The MCU leakage signal detection circuit 10 controls the thyristor 22 to be turned off, maintaining the power supply to the coil 3 and engaging the switch 2.

[0038] When the LN line leakage and self-test control circuit 11 or the PE line fault current detection control circuit 12 detects a leakage signal, the MCU leakage signal detection circuit 10 transmits the received leakage signal to the MCU control circuit 6 and simultaneously controls the thyristor 22 to conduct, de-energizing coil 3 and preventing switch 2 from closing. Switch 2 disconnects the input power. The MCU control circuit 6 then controls the TEST button and the leakage alarm circuit 19 to illuminate, sounding an alarm. After the user investigates and addresses the leakage incident, the leakage signal disappears, and the MCU leakage signal detection circuit 10 controls the thyristor 22 to open. The user must manually press the reset switch RESET of the power-on reset circuit 18. Upon receiving the reset signal from the power-on reset circuit 18, the MCU control circuit 6 outputs a high level, driving the high-current pickup circuit 7 to output a high current, energizing coil 3 and closing switch 2. The low-current pickup circuit 8 then outputs a low current to maintain coil 3 energized, closing switch 2. The MCU control circuit 6 then controls the TEST button and the leakage alarm circuit 19 to de-illuminate, completing the reset and power-on process. When neither the LN line leakage and self-test control circuit 11 nor the PE line fault current detection control circuit 12 detects a leakage signal, the MCU leakage signal detection circuit 10 will not output a leakage signal to the MCU control circuit 6. The MCU leakage signal detection circuit 10 controls the thyristor 22 to disconnect, maintaining the coil 3 energized to close the switch 2.

[0039] like Figure 1-2As shown, a grounding anomaly indication circuit 13 is connected between the neutral and ground wires of the power supply terminal 1. It illuminates when the ground wire is energized, and remains OFF when the ground wire of the power supply terminal 1 is properly grounded. A power indicator circuit 14 is connected between the live wire of the output terminal 4 and the neutral wire of the power supply terminal 1. It illuminates when the live wire of the output terminal 4 is energized, and remains OFF when the live wire of the output terminal 4 is de-energized. The MCU control circuit 6 is connected to a test circuit and a leakage alarm indication circuit 19, which illuminate when leakage occurs. These circuits remain OFF when leakage does not occur. The MCU control circuit 6 is connected to a power-on reset circuit 18 for manual reset. After troubleshooting a leakage event, the user presses the reset switch RESET to reset the circuit. The MCU control circuit 6 is powered by an MCU control power supply RC step-down circuit 16. The LN line leakage and self-test control circuit 11 and the PE line fault current detection control circuit 12 are powered by a leakage control power supply RC step-down circuit 20. The coil low-current pickup circuit 8, the MCU control power supply RC step-down circuit 16, and the leakage control power supply RC step-down circuit 20 all adopt RC step-down circuits, which are beneficial to reducing heat generation during operation and power loss during standby, and are green and environmentally friendly.

[0040] like Figure 2 As shown, the specific structure of the power supply anti-shake detection circuit 5 is as follows: the power supply anti-shake detection circuit 5 includes a transistor Q2, the emitter of the transistor Q2 is electrically connected to the neutral line of the power supply terminal 1, the base of the transistor Q2 is electrically connected to one end of a resistor R34 and one end of a resistor R35, the other end of the resistor R35 is electrically connected to one end of a resistor R36, the other end of the resistor R36 is electrically connected to the live line of the power supply terminal 1, the other end of the resistor R34 is electrically connected to the neutral line of the power supply terminal 1, and the collector of the transistor Q2 is electrically connected to pin P00 of the MCU control circuit 6. The power supply anti-shake detection circuit 5 can process the voltage waveform of the input power supply in real time and output the processed input power supply voltage waveform to the MCU control circuit 6 so that the voltage waveform meets the electrical input requirements of pin P00 of the MCU control circuit 6.

[0041] like Figure 2As shown, the specific structure of the coil high-current pickup circuit 7 is as follows: the coil high-current pickup circuit 7 includes a control chip U2, a pin LED+ of the control chip U2 electrically connected to one end of a resistor R7, the other end of the resistor R7 electrically connected to a pin P01 of the MCU control circuit 6, a pin LED- of the control chip U2 electrically connected to the neutral line of the power supply terminal 1, a pin Terminal1 of the control chip U2 electrically connected to one end of the coil 3, a pin Terminal2 of the control chip U2 electrically connected to the cathode of a diode D9, a positive electrode of the diode D9 electrically connected to one end of a resistor R3, the other end of the resistor R3 electrically connected to the live line of the power supply terminal 1, and the other end of the coil 3 electrically connected to the neutral line of the power supply terminal 1. The coil high-current pickup circuit 7 can receive the high level output by the MCU control circuit 6 and output a high current while the high level lasts, causing the coil 3 to complete the action of attracting the switch 2 under the drive of the high current. When the MCU control circuit 6 stops outputting a high level to the coil high-current pickup circuit 7, the coil high-current pickup circuit 7 no longer outputs a high current to the coil 3, and the coil low-current pickup circuit 8 outputs a low current to keep the coil 3 energized and the switch 2 closed. This prevents the coil high-current pickup circuit 7 from outputting a high current for a long time, consuming too much power and increasing heat generation, thereby reducing power loss during standby mode and being environmentally friendly.

[0042] like Figure 2 As shown, the specific structure of the coil low-current pickup circuit 8 is as follows: the coil low-current pickup circuit 8 includes a resistor R1A, one end of which is electrically connected to one end of a resistor R1B. The other end of the resistor R1B is electrically connected to one end of a capacitor C1 and the live wire of the power supply terminal 1. The other end of the resistor R1A is electrically connected to the other end of the capacitor C1, the cathode of a diode D5, and the anode of a diode D7. The anode of the diode D5 is electrically connected to the neutral wire of the power supply terminal 1, the cathode of the polarity capacitor C6, and one end of the coil 3. The cathode of the diode D7 is electrically connected to the anode of the polarity capacitor C6 and the other end of the coil 3. After the coil 3 completes the action of pulling in the switch 2, the coil low-current pickup circuit 8 outputs a low current to keep the coil 3 energized and the switch 2 engaged. The coil low-current pickup circuit 8 adopts the structure of a resistor-capacitor step-down circuit, with a low output current. This ensures that the coil 3 is energized for a long time, while also reducing heat generation during operation and power loss during standby mode, thus achieving environmental protection.

[0043] like Figure 2As shown, the specific structure of the MCU leakage signal detection circuit 10 is as follows: the MCU leakage signal detection circuit 10 includes a transistor Q4, the collector of the transistor Q4 is electrically connected to one end of the resistor R8 and the pin P02 of the MCU control circuit 6, the other end of the resistor R8 is electrically connected to the pin VDD of the MCU control circuit 6, the emitter of the transistor Q4 is electrically connected to one end of the capacitor C8 and the neutral line of the power supply terminal 1, the base of the transistor Q4 is electrically connected to the other end of the capacitor C8 and one end of the resistor R9, and the other end of the resistor R9 is electrically connected to the pin VDD of the resistor R10. One end of the dual-way switching diode Q3 is electrically connected to the output end of the dual-way switching diode Q3, one input end of the dual-way switching diode Q3 is electrically connected to the resistor R19, the resistor R19 is electrically connected to the pin TRIG of the detection chip U1, the other input end of the dual-way switching diode Q3 is electrically connected to the pin SCR of the detection chip U1E, the other end of the resistor R10 is electrically connected to one end of the capacitor C9 and the control electrode of the thyristor 22, the other end of the capacitor C9 is electrically connected to the neutral line of the power supply terminal 1 and the negative electrode of the thyristor 22, and the positive electrode of the thyristor 22 is electrically connected to one end of the coil 3.

[0044] like Figure 2As shown, the specific structure of the LN line leakage and self-test control circuit 11 is as follows: the LN line leakage and self-test control circuit 11 includes a detection chip U1, a pin VDDRC of the detection chip U1 is electrically connected to the pin VDD of the MCU control circuit 6 and one end of the capacitor C17, a pin STP of the detection chip U1 is electrically connected to the other end of the capacitor C17 and one end of the resistor R22, the other end of the resistor R22 is electrically connected to the collector of the transistor Q6, the emitter of the transistor Q6 is electrically connected to the neutral line of the power supply 1, a pin CFRC of the detection chip U1 is electrically connected to one end of the capacitor C16, the other end of the capacitor C16 is electrically connected to the neutral line of the power supply 1, and the detection chip The pin TRIG of U1 is electrically connected to one end of the resistor R19 and the cathode of the diode D12. The pin FOUT of the detection chip U1 is electrically connected to the anode of the diode D12, one end of the resistor R20, and one input end of the dual-way switch diode Q5. The other end of the resistor R20 is electrically connected to the base of the transistor Q6. The other input end of the dual-way switch diode Q5 is electrically connected to the pin P05 of the MCU control circuit 6. The output end of the dual-way switch diode Q5 is electrically connected to one end of the resistor R21. The pin EOL of the detection chip U1 is electrically connected to one end of the resistor R27. The other end of the resistor R27 is electrically connected to the anode of the light-emitting diode D13. The negative electrode of D13 is electrically connected to the neutral line of the power supply terminal 1, the pin VDDST of the detection chip U1 is electrically connected to one end of the resistor R6 and one end of the capacitor C10, the other end of the capacitor C10 is electrically connected to the neutral line of the power supply terminal 1, the pin STIN of the detection chip U1 is electrically connected to one end of the resistor R26 and the positive electrode of the diode D14, the other end of the resistor R26 is electrically connected to the negative electrode of the diode D14, one end of the coil 3, and the positive electrode of the thyristor 22, the pin GNDST of the detection chip U1 is electrically connected to the pin GNDRC of the detection chip U1 and the neutral line of the power supply terminal 1, the pin RCT2 of the detection chip U1 is electrically connected to one end of the capacitor C18, the resistor One end of R25 is electrically connected, the other end of the resistor R25 is electrically connected to one end of the resistor R23 and one end of the current transformer ZCT1, the other end of the current transformer ZCT1 is electrically connected to the other end of the resistor R23 and one end of the resistor R24, the other end of the resistor R24 is electrically connected to the other end of the capacitor C18 and the pin RCT1 of the detection chip U1, the live wire and the neutral wire of the output terminal 4, the connecting line between the emitter of the transistor Q1 of the over-temperature protection control circuit 9 and the neutral wire of the power supply terminal 1, and the connecting line between the test switch TEST of the TEST simulated leakage circuit 15 and the live wire of the output terminal 4 all pass through the center of the current transformer ZCT1.When the live wire or the neutral wire of the output terminal 4 leaks, the current transformer ZCT1 generates an induced current, and the pin TRIG of the detection chip U1 outputs a leakage signal to the MCU leakage signal detection circuit 10 .

[0045] During self-test, the pin FOUT of the detection chip U1 outputs an analog fault excitation signal in the negative half-power frequency cycle to turn on the over-temperature protection control circuit 9, the current transformer ZCT1 generates an induced current, and the pin TRIG of the detection chip U1 outputs a leakage signal to the MCU leakage signal detection circuit 10. At the same time, the detection chip U1 detects the input signal status of the pin STIN in real time. When the input signal state of the pin STIN of the detection chip U1 is a high level in the positive half-power frequency cycle and a low level in the negative half-power frequency cycle, the self-test module of the detection chip U1 determines that the functions of the coil 3, the thyristor 22, the leakage protection module of the detection chip U1, and the current transformer ZCT1 are all normal, the pin EOL of the detection chip U1 does not output a fault alarm signal, and the self-test fault alarm circuit 21 does not light up; when the input signal of the pin STIN of the detection chip U1 is a continuous high level signal or a low level signal, the self-test module of the detection chip U1 determines that one of the coil 3, the thyristor 22, the leakage protection module of the detection chip U1, and the current transformer ZCT1 is damaged, the pin EOL of the detection chip U1 outputs a fault alarm signal to drive the self-test fault alarm circuit 21 to light up, and issues an alarm prompt.

[0046] like Figure 2 As shown, the specific structure of the PE line fault current detection control circuit 12 is as follows: the PE line fault current detection control circuit 12 includes a detection chip U1E, the pin Neutral of the detection chip U1E is electrically connected to one end of the capacitor C13 and the neutral line of the power supply terminal 1, the pin Line of the detection chip U1E is electrically connected to one end of the resistor R6 and one end of the capacitor C10, the pin VREF of the detection chip U1E is electrically connected to the other end of the capacitor C13, one end of the capacitor C14, one end of the resistor R29, and the current One end of the current transformer ZCT2 is electrically connected, and the other end of the current transformer ZCT2 is electrically connected to the other end of the resistor R29, the other end of the capacitor C14, and one end of the resistor R30. The other end of the resistor R30 is electrically connected to one end of the capacitor C15, one end of the resistor R28, and the pin VFB of the detection chip U1E. The pin AmpOUT of the detection chip U1E is electrically connected to the other end of the capacitor C15 and the other end of the resistor R28. The ground wire of the output terminal 4 passes through the center of the current transformer ZCT2. When the ground wire of the output terminal 4 fails and becomes energized, the current transformer ZCT2 generates an induced current, and the detection chip U1E outputs a leakage signal to the MCU leakage signal detection circuit 10.

[0047] like Figure 2As shown, the specific structure of the over-temperature detection circuit 17 is as follows: the over-temperature detection circuit 17 includes a thermistor R13, one end of the thermistor R13 is electrically connected to the neutral line of the power supply terminal 1 and one end of the capacitor C5, the other end of the thermistor R13 is electrically connected to one end of the resistor R14 and one end of the resistor R15, the other end of the resistor R14 is electrically connected to the pin VDD of the MCU control circuit 6, and the other end of the resistor R15 is electrically connected to the pin P03 of the MCU control circuit 6 and the other end of the capacitor C5. The specific structure of the over-temperature protection control circuit 9 is as follows: the over-temperature protection control circuit 9 includes a transistor Q1, the collector of the transistor Q1 is electrically connected to one end of the resistor R33B, the other end of the resistor R33B is electrically connected to one end of the resistor R33A, the other end of the resistor R33A is electrically connected to the negative electrode of the diode D8, the positive electrode of the diode D8 is electrically connected to the live wire of the power supply terminal 1, the emitter of the transistor Q1 is electrically connected to the neutral wire of the power supply terminal 1, and the base of the transistor Q1 is electrically connected to one end of the resistor R21.

[0048] Overtemperature detection circuit 17 transmits the detected live or neutral pin temperature to MCU control circuit 6. When the pin temperature exceeds the set temperature, MCU control circuit 6 turns on overtemperature protection control circuit 9, generating an induced current in current transformer ZCT1. Pin TRIG of detection chip U1 outputs a leakage signal to MCU leakage signal detection circuit 10. MCU leakage signal detection circuit 10 transmits the received leakage signal to MCU control circuit 6 and simultaneously turns on thyristor 22, de-energizing coil 3 and preventing switch 2 from closing. Switch 2 disconnects the input power. When the pin temperature falls below the set temperature, MCU control circuit 6 turns off overtemperature protection control circuit 9, eliminating the leakage signal. MCU leakage signal detection circuit 10 turns off thyristor 22, and MCU control circuit 6 outputs a high level, driving high-current coil pickup circuit 7 to output a high current, energizing coil 3 and closing switch 2. Low-current coil pickup circuit 8 then outputs a low current to maintain coil 3 energized, closing switch 2, and connecting switch 2 to the input power. When the input power voltage waveform is non-sinusoidal, the MCU control circuit 6 can activate the over-temperature protection control circuit 9 to generate a simulated leakage signal, actively disconnecting the input power supply to prevent damage to the load devices and extend their service life. The LN line leakage and self-test control circuit 11 outputs a simulated fault excitation signal to activate the over-temperature protection control circuit 9 and generate a simulated leakage signal. The LN line leakage and self-test control circuit 11 then detects the proper functioning of the coil 3, thyristor 22, the leakage protection module of the detection chip U1, and the current transformer ZCT1 by monitoring the input signal status of the STIN pin.

[0049] like Figure 2As shown, the specific structure of the TEST simulated leakage circuit 15 is as follows: the TEST simulated leakage circuit 15 includes a test switch TEST, one end of the test switch TEST is electrically connected to the live wire of the output terminal 4, the other end of the test switch TEST is electrically connected to one end of the resistor R32B, the other end of the resistor R32B is electrically connected to one end of the resistor R32A, and the other end of the resistor R32A is electrically connected to the neutral wire of the power supply terminal 1. When the user presses the test switch TEST, the TEST simulated leakage circuit 15 is turned on, the current transformer ZCT1 generates an induced current, and the detection chip U1 outputs a leakage signal to the MCU leakage signal detection circuit 10. The MCU leakage signal detection circuit 10 transmits the received leakage signal to the MCU control circuit 6 and simultaneously controls the thyristor 22 to turn on, so that the coil 3 is de-energized and the switch 2 is not attracted. The switch 2 disconnects the input power supply, and the MCU control circuit 6 controls the TEST key and the leakage alarm prompt circuit 19 to illuminate, issuing an alarm prompt. The user must manually press the reset switch RESET of the power-on reset circuit 18. After receiving the reset signal of the power-on reset circuit 18, the MCU control circuit 6 outputs a high level to drive the coil high-current attraction circuit 7 to output a large current so that the coil 3 is energized and the switch 2 is attracted. The coil low-current attraction circuit 8 outputs a small current to maintain the coil 3 energized and the switch 2 is attracted. The MCU control circuit 6 controls the TEST button and the leakage alarm prompt circuit 19 to not light up, completing the reset and power on.

Claims

1. A control circuit for a leakage protection switch device with automatic reset and self-test function, characterized by: The invention comprises a power supply terminal (1) connected to an input power supply, an output terminal (4) connected to a load, and an MCU control circuit (6); a live wire, a neutral wire, and a ground wire between the power supply terminal (1) and the output terminal (4) are connected to a switch (2) that can automatically reset and energize after being attracted by a coil (3); the MCU control circuit (6) is connected to a power supply anti-shake detection circuit (5) for detecting the positive and negative periodic voltage waveforms of the input power supply, and a coil large current for the power supply anti-shake detection circuit (5) to output a large current to energize the coil (3) and attract the switch (2) when the input power supply voltage waveform is detected to be a sine wave within a preset time. A current pickup circuit (7), wherein the power supply end (1) is connected to a coil low current pickup circuit (8) for maintaining the coil (3) energized and attracted after the coil (3) attracts the switch (2); the coil (3) is connected to an LN line leakage and self-detection control circuit (11) for respectively detecting faults of the coil (3) and the thyristor (22) and performing fault self-detection on the detection chip U1 and the current transformer ZCT1; the LN line leakage and self-detection control circuit (11) is connected to a self-detection fault alarm circuit (21) for alarming when the LN line leakage and self-detection control circuit (11) detects a fault; The MCU control circuit (6) is further connected to an MCU leakage signal detection circuit (10), and the MCU leakage signal detection circuit (10) is connected to an LN line leakage and self-checking control circuit (11) for detecting a live line or neutral line leakage signal of the output end (4), and a PE line fault current detection control circuit (12) for detecting a ground line leakage signal of the output end (4). When the LN line leakage and self-checking control circuit (11) or the PE line fault current detection control circuit (12) detects a leakage signal, the MCU leakage signal detection circuit (10) outputs the leakage signal to the MCU control circuit (6) and controls the thyristor (22) to conduct, so that the coil (3) is de-energized and the switch (2) is not attracted. The MCU control circuit (6) is connected to an over-temperature detection circuit (17) for detecting the temperature of the live or neutral pins, and an over-temperature protection control circuit (9) for outputting a simulated leakage signal when the pin temperature exceeds a set temperature. The live wire of the output end (4) is connected to a TEST simulated leakage circuit (15) for outputting a simulated leakage signal for manual testing. When the LN line leakage and self-checking control circuit (11) detects the simulated leakage signal of the over-temperature protection control circuit (9) or the TEST simulated leakage circuit (15), the MCU leakage signal detection circuit (10) outputs the simulated leakage signal to the MCU control circuit (6) and controls the thyristor (22) to conduct, so that the coil (3) is de-energized and the switch (2) is not attracted. A grounding abnormality prompt circuit (13) that emits light when the ground wire is energized is connected between the neutral wire and the ground wire of the power supply end (1); a power indicator circuit (14) that emits light when the live wire of the output end (4) is energized is connected between the live wire of the output end (4) and the neutral wire of the power supply end (1); the MCU control circuit (6) is powered by an MCU control power supply resistance-capacitance step-down circuit (16); the MCU control circuit (6) is connected to a power-on reset circuit (18) for manual reset, a TEST circuit for emitting light when leakage occurs, and a leakage alarm indicator circuit (19); the LN line leakage and self-test control circuit (11) and the PE line fault current detection control circuit (12) are powered by a leakage control power supply resistance-capacitance step-down circuit (20).

2. The control circuit of a leakage protection switch device with automatic reset and self-test function according to claim 1, characterized in that: The power supply anti-shake detection circuit (5) includes a transistor Q2, the emitter of the transistor Q2 is electrically connected to the neutral line of the power supply end (1), the base of the transistor Q2 is electrically connected to one end of a resistor R34 and one end of a resistor R35, the other end of the resistor R35 is electrically connected to one end of a resistor R36, the other end of the resistor R36 is electrically connected to the live line of the power supply end (1), the other end of the resistor R34 is electrically connected to the neutral line of the power supply end (1), and the collector of the transistor Q2 is electrically connected to pin P00 of the MCU control circuit (6).

3. The control circuit of the leakage protection switch device with automatic reset and self-checking function according to claim 1, characterized in that: The coil high current pickup circuit (7) includes a control chip U2, a pin LED+ of the control chip U2 is electrically connected to one end of a resistor R7, the other end of the resistor R7 is electrically connected to a pin P01 of the MCU control circuit (6), a pin LED- of the control chip U2 is electrically connected to the neutral line of the power supply end (1), a pin Terminal1 of the control chip U2 is electrically connected to one end of the coil (3), a pin Terminal2 of the control chip U2 is electrically connected to the negative electrode of a diode D9, a positive electrode of the diode D9 is electrically connected to one end of a resistor R3, the other end of the resistor R3 is electrically connected to the live wire of the power supply end (1), and the other end of the coil (3) is electrically connected to the neutral line of the power supply end (1).

4. The control circuit of a leakage protection switch device with automatic reset and self-checking function according to claim 1, characterized in that: The small current pickup circuit (8) includes a resistor R1A, one end of the resistor R1A is electrically connected to one end of the resistor R1B, the other end of the resistor R1B is electrically connected to one end of the capacitor C1 and the live wire of the power supply terminal (1), the other end of the resistor R1A is electrically connected to the other end of the capacitor C1, the negative electrode of the diode D5, and the positive electrode of the diode D7, the positive electrode of the diode D5 is electrically connected to the neutral wire of the power supply terminal (1), the negative electrode of the polarity capacitor C6, and one end of the coil (3), and the negative electrode of the diode D7 is electrically connected to the positive electrode of the polarity capacitor C6 and the other end of the coil (3).

5. The control circuit of the leakage protection switch device with automatic reset and self-checking function according to claim 1, characterized in that: The MCU leakage signal detection circuit (10) includes a transistor Q4, the collector of the transistor Q4 is electrically connected to one end of a resistor R8 and a pin P02 of the MCU control circuit (6), the other end of the resistor R8 is electrically connected to a pin VDD of the MCU control circuit (6), the emitter of the transistor Q4 is electrically connected to one end of a capacitor C8 and a neutral line of the power supply terminal (1), the base of the transistor Q4 is electrically connected to the other end of the capacitor C8 and one end of a resistor R9, the other end of the resistor R9 is electrically connected to one end of a resistor R10 and the zero line of a dual-way switch diode Q3. The output end is electrically connected, one input end of the dual-way switch diode Q3 is electrically connected to the resistor R19, the resistor R19 is electrically connected to the pin TRIG of the detection chip U1, the other input end of the dual-way switch diode Q3 is electrically connected to the pin SCR of the detection chip U1E, the other end of the resistor R10 is electrically connected to one end of the capacitor C9 and the control electrode of the thyristor (22), the other end of the capacitor C9 is electrically connected to the zero line of the power supply end (1) and the negative electrode of the thyristor (22), and the positive electrode of the thyristor (22) is electrically connected to one end of the coil (3).

6. The control circuit of the leakage protection switch device with automatic reset and self-checking function according to claim 2, characterized in that: The LN line leakage and self-checking control circuit (11) includes a detection chip U1, a pin VDDRC of the detection chip U1 is electrically connected to a pin VDD of the MCU control circuit (6) and one end of a capacitor C17, a pin STP of the detection chip U1 is electrically connected to the other end of the capacitor C17 and one end of a resistor R22, the other end of the resistor R22 is electrically connected to the collector of the transistor Q6, the emitter of the transistor Q6 is electrically connected to the neutral line of the power supply terminal (1), a pin CFRC of the detection chip U1 is electrically connected to one end of the capacitor C16, the other end of the capacitor C16 is electrically connected to the neutral line of the power supply terminal (1), and a pin TRIG of the detection chip U1 is electrically connected to one end of the resistor R19. The pin FOUT of the detection chip U1 is electrically connected to the positive electrode of the diode D12, one end of the resistor R20, and one input end of the dual-way switch diode Q5. The other end of the resistor R20 is electrically connected to the base of the transistor Q6. The other input end of the dual-way switch diode Q5 is electrically connected to the pin P05 of the MCU control circuit (6). The output end of the dual-way switch diode Q5 is electrically connected to one end of the resistor R21. The pin EOL of the detection chip U1 is electrically connected to one end of the resistor R27. The other end of the resistor R27 is electrically connected to the positive electrode of the light-emitting diode D13. The negative electrode of the light-emitting diode D13 is electrically connected to the zero voltage of the power supply terminal (1). The pin VDDST of the detection chip U1 is electrically connected to one end of the resistor R6 and one end of the capacitor C10, and the other end of the capacitor C10 is electrically connected to the neutral line of the power supply terminal (1). The pin STIN of the detection chip U1 is electrically connected to one end of the resistor R26 and the positive electrode of the diode D14, and the other end of the resistor R26 is electrically connected to the negative electrode of the diode D14, one end of the coil (3), and the positive electrode of the thyristor (22). The pin GNDST of the detection chip U1 is electrically connected to the pin GNDRC of the detection chip U1 and the neutral line of the power supply terminal (1). The pin RCT2 of the detection chip U1 is electrically connected to one end of the capacitor C18 and one end of the resistor R25. The other end of the resistor R25 is electrically connected to one end of the resistor R23 and one end of the current transformer ZCT1, the other end of the current transformer ZCT1 is electrically connected to the other end of the resistor R23 and one end of the resistor R24, the other end of the resistor R24 is electrically connected to the other end of the capacitor C18 and the pin RCT1 of the detection chip U1, the live wire and the neutral wire of the output terminal (4), the connecting wire between the emitter of the transistor Q1 of the over-temperature protection control circuit (9) and the neutral wire of the power supply terminal (1), and the connecting wire between the test switch (TEST) of the TEST simulated leakage circuit (15) and the live wire of the output terminal (4) all pass through the center of the current transformer ZCT1;The PE line fault current detection control circuit (12) includes a detection chip U1E, a pin Neutral of the detection chip U1E is electrically connected to one end of the capacitor C13 and the neutral line of the power supply end (1), a pin Line of the detection chip U1E is electrically connected to one end of the resistor R6 and one end of the capacitor C10, a pin VREF of the detection chip U1E is electrically connected to the other end of the capacitor C13, one end of the capacitor C14, one end of the resistor R29, and one end of the current transformer ZCT2, the other end of the current transformer ZCT2 is electrically connected to the other end of the resistor R29, the other end of the capacitor C14, and one end of the resistor R30, the other end of the resistor R30 is electrically connected to one end of the capacitor C15, one end of the resistor R28, and a pin VFB of the detection chip U1E, a pin AmpOUT of the detection chip U1E is electrically connected to the other end of the capacitor C15 and the other end of the resistor R28, and the ground wire of the output end (4) passes through the center of the current transformer ZCT2. ; 7. The control circuit of a leakage protection switch device with automatic reset and self-checking function according to claim 1, characterized in that: The over-temperature detection circuit (17) includes a thermistor R13, one end of the thermistor R13 is electrically connected to the zero line of the power supply end (1) and one end of the capacitor C5, the other end of the thermistor R13 is electrically connected to one end of the resistor R14 and one end of the resistor R15, the other end of the resistor R14 is electrically connected to the pin VDD of the MCU control circuit (6), the other end of the resistor R15 is electrically connected to the pin P03 of the MCU control circuit (6) and the other end of the capacitor C5, the over-temperature protection control circuit (9) includes a transistor Q1, the collector of the transistor Q1 is electrically connected to one end of the resistor R33B, the other end of the resistor R33B is electrically connected to one end of the resistor R33A, The other end of the resistor R33A is electrically connected to the negative electrode of the diode D8, the positive electrode of the diode D8 is electrically connected to the live wire of the power supply end (1), the emitter of the transistor Q1 is electrically connected to the neutral wire of the power supply end (1), the base of the transistor Q1 is electrically connected to one end of the resistor R21, and the TEST simulated leakage circuit (15) includes a test switch (TEST), one end of the test switch (TEST) is electrically connected to the live wire of the output end (4), the other end of the test switch (TEST) is electrically connected to one end of the resistor R32B, the other end of the resistor R32B is electrically connected to one end of the resistor R32A, and the other end of the resistor R32A is electrically connected to the neutral wire of the power supply end (1).

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