Protective device and distribution box with the same

Abstract

An embodiment of the present invention discloses a protection device and a distribution box with the protection device, the protection device comprising: a signal detection circuit, used to detect a first voltage between a common grounding point and a starting point of a local ground wire, a second voltage between the common grounding point and an end point of the local ground wire, and a third voltage between the starting point of the ground wire and the end point of the local ground wire; and a controller, electrically connected to the signal detection circuit and the leakage protection circuit, respectively; when any one of the ratio of a first difference to an average value of a first voltage detected and obtained within a preset time period before the current moment, the ratio of a second difference to an average value of a second voltage detected and obtained within a preset time period before the current moment, and the ratio of a third difference to an average value of a third voltage detected and obtained within a preset time period before the current moment is greater than a preset ratio threshold, the controller outputs a trigger signal to the leakage protection circuit to trigger the leakage protection circuit to disconnect.

Description

Technical Field

[0001] The invention relates to the field of power protection, and in particular to a protection device and a distribution box having the protection device. Background Art

[0002] Common protection devices for electrical equipment include overcurrent protectors and leakage protectors. Overcurrent protectors are used to limit current to prevent overload and heat generation of wires in electrical equipment, while leakage protectors are used to detect leakage to protect users. However, the above current limiting and leakage detection strategies only play a certain protective role. Summary of the invention

[0003] In view of the above technical problems, an embodiment of the present invention provides a protection device and a distribution box having the protection device.

[0004] A first aspect of an embodiment of the present invention provides a protection device for a distribution box, the distribution box comprising a leakage protection circuit and a local ground wire, the leakage protection circuit is used to access the live wire and the neutral wire of the mains to access the power supply, and the local ground wire is connected in series with the public ground wire; the protection device comprises:

[0005] A signal detection circuit, used to detect a first voltage between a common ground point and a starting point of a local ground line, a second voltage between the common ground point and an end point of the local ground line, and a third voltage between the starting point of the local ground line and an end point of the local ground line; and

[0006] A controller, electrically connected to the signal detection circuit and the leakage protection circuit respectively;

[0007] When any one of the ratio of the first difference to the average value of the first voltage detected and obtained within the preset time period before the current moment, the ratio of the second difference to the average value of the second voltage detected and obtained within the preset time period before the current moment, and the ratio of the third difference to the average value of the third voltage detected and obtained within the preset time period before the current moment is greater than a preset ratio threshold, the controller outputs a trigger signal to the leakage protection circuit to trigger the leakage protection circuit to disconnect;

[0008] Wherein, the first difference is the difference between the first voltage detected at the current moment and the average value of the first voltage detected within a preset time period before the current moment;

[0009] The second difference is a difference between the second voltage detected at the current moment and an average value of the second voltage detected within a preset time period before the current moment;

[0010] The third difference is a difference between the third voltage detected at the current moment and an average value of the third voltage detected within a preset time period before the current moment.

[0011] Optionally, the signal detection circuit includes at least three comparators;

[0012] A non-inverting input terminal of one of the at least three comparators is used to connect the common ground point and one of the local ground line starting points, and an inverting input terminal is used to connect the common ground point and the other of the local ground line starting points;

[0013] A non-inverting input terminal of one of the at least three comparators is used to connect the common ground point and one of the local ground line terminals, and an inverting input terminal is used to connect the common ground point and the other of the local ground line terminals;

[0014] And the non-inverting input terminal of at least one of the three comparators is used to connect to one of the local ground starting point and the local ground end point, and the inverting input terminal is used to connect to the other of the local ground starting point and the local ground end point.

[0015] Optionally, the number of the comparators is 6, including a first comparator, a second comparator, a third comparator, a fourth comparator, a fifth comparator and a sixth comparator;

[0016] Wherein, the non-inverting input terminal of the first comparator is used to connect to the common ground point, and the inverting input terminal is used to connect to the starting point of the local ground line;

[0017] The non-inverting input terminal of the second comparator is used to connect to the common ground point, and the inverting input terminal is used to connect to the local ground terminal;

[0018] The non-inverting input terminal of the third comparator is used to connect to the starting point of the local ground line, and the inverting input terminal is used to connect to the end point of the local ground line;

[0019] The non-inverting input terminal of the fourth comparator is used to connect to the starting point of the local ground line, and the inverting input terminal is used to connect to the common ground point;

[0020] The non-inverting input terminal of the fifth comparator is used to connect to the local ground terminal, and the inverting input terminal is used to connect to the common ground point;

[0021] The non-inverting input terminal of the sixth comparator is used to connect to the end point of the local ground line, and the inverting input terminal is used to connect to the starting point of the local ground line.

[0022] Optionally, the controller includes a single chip microcomputer.

[0023] Optionally, the protection device further comprises a test button electrically connected between the local ground wire starting point and the local ground wire end point to disconnect or connect the electrical connection between the local ground wire starting point and the local ground wire end point;

[0024] When the test button is disconnected, the electrical connection between the local ground wire starting point and the local ground wire end point is disconnected, and the controller is used to obtain the state of the leakage protection circuit to determine whether the leakage protection circuit is turned on.

[0025] Optionally, the protection device further includes a load, and a ground wire of the load is connected in series with a starting point of the local ground wire or an end point of the local ground wire.

[0026] A second aspect of an embodiment of the present invention provides a distribution box, the distribution box comprising:

[0027] The leakage protection circuit is used to connect the live wire and the neutral wire of the mains to access the power supply;

[0028] a local ground wire connected in series with the common ground wire; and

[0029] The protection device described in the first aspect of the embodiment of the present invention.

[0030] Optionally, the common ground wire and the local ground wire are connected in series via a water-immersion touchless protector.

[0031] Optionally, the leakage protection circuit includes a leakage protector and a leakage switch connected in series, the leakage protector is used to access the live wire and the neutral wire of the mains, and the leakage protection switch is electrically connected to the controller of the protection device.

[0032] Optionally, the leakage switch is a leakage air switch.

[0033] In the technical solution provided by the embodiment of the present invention, a signal detection circuit is used to monitor in real time a first voltage between a common grounding point and a starting point of a local ground wire, a second voltage between a common grounding point and an end point of a local ground wire, and a third voltage between a starting point of a local ground wire and an end point of a local ground wire. When any one of the first voltage, the second voltage and the third voltage changes greatly, the controller controls the leakage protection circuit to disconnect, thereby cutting off the power supply, thereby further ensuring the safety of electricity use. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of a protection device in one embodiment of the present invention;

[0035] Figure 2 It is a structural schematic diagram of a distribution box in one embodiment of the present invention;

[0036] Figure 3 is a circuit diagram of a protection device in one embodiment of the present invention;

[0037] Figure 4A A schematic diagram of correct load connection of a protection device in one embodiment of the present invention;

[0038] Figure 4B A schematic diagram of a load miswiring for a protection device;

[0039] Figure 4C This is another load miswiring diagram for the protection device.

[0040] Reference numerals:

[0041] 100: leakage protection circuit; 110: leakage protector; 120: leakage switch;

[0042] 200: local ground line; 210: starting point of local ground line; 220: end point of local ground line;

[0043] 300: protection device; 310: signal detection circuit; 311: comparator; R1: first resistor; R2: second resistor; 320: controller; 330: test button; 340: load;

[0044] 400: Water immersion non-touch protector. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0046] It should be noted that the following embodiments can be combined if there is no conflict.

[0047] Figure 1 is a schematic diagram of the structure of a protection device in an embodiment of the present invention, Figure 2 The protection device of the embodiment of the present invention can be used in a distribution box or other distribution devices.

[0048] Please combine Figure 1 and Figure 2The distribution box of the embodiment of the present invention may include a leakage protection circuit 100 and a local ground wire 200, wherein the leakage protection circuit 100 is used to access the live wire and the neutral wire of the mains to access the power supply and supply power to the distribution box. In this embodiment, the local ground wire 200 is connected in series with the public ground wire. It should be noted that the public ground wire refers to the ground wire introduced by the power company, and the local ground wire 200 refers to the ground wire added to the distribution box. The local wire is used to absorb excess charge when the distribution box leaks. The local ground wire 200 and the public ground wire can be copper wires with a diameter of 6 mm and a length of at least 20 meters, but are not limited to this. The voltage of the mains power in this embodiment can be 110V or 220V.

[0049] Please combine again Figure 1 and Figure 2 The protection device 300 of the embodiment of the present invention may include a signal detection circuit 310 and a controller 320 , wherein the controller 320 is electrically connected to the signal detection circuit 310 and the leakage protection circuit 100 , respectively.

[0050] In this embodiment, the signal detection circuit 310 is used to detect a first voltage between the common ground point and the local ground starting point 210 , a second voltage between the common ground point and the local ground end point 220 , and a third voltage between the local ground starting point 210 and the local ground end point 220 .

[0051] The controller 320 is used to output a trigger signal to the leakage protection circuit 100 to trigger the leakage protection circuit 100 to disconnect when any of the ratio of the first difference to the average value of the first voltage detected and obtained within the preset time period before the current moment, the ratio of the second difference to the average value of the second voltage detected and obtained within the preset time period before the current moment, and the third difference to the average value of the third voltage detected and obtained within the preset time period before the current moment is greater than a preset ratio threshold. Among them, the first difference is the difference between the first voltage detected and obtained at the current moment and the average value of the first voltage detected and obtained within the preset time period before the current moment; the second difference is the difference between the second voltage detected and obtained at the current moment and the average value of the second voltage detected and obtained within the preset time period before the current moment; the third difference is the difference between the third voltage detected and obtained at the current moment and the average value of the third voltage detected and obtained within the preset time period before the current moment.

[0052] The size of the preset ratio threshold can be set as needed. For example, the preset ratio threshold can be 3%. When any ratio exceeds the preset ratio threshold, it means that any one of the first voltage, the second voltage and the third voltage has changed significantly, the common grounding point, the local ground wire starting point 210 and the local ground wire end point 220 may not share a common ground, and there are risks such as leakage and overcurrent in the line. The protection device 300 of the embodiment of the present invention monitors the first voltage between the common grounding point and the local ground wire starting point 210, the second voltage between the common grounding point and the local ground wire end point 220, and the third voltage between the local ground wire starting point 210 and the local ground wire end point 220 in real time through the signal detection circuit 310. When any one of the first voltage, the second voltage and the third voltage changes significantly, the controller 320 controls the leakage protection circuit 100 to disconnect, thereby cutting off the power supply (i.e., cutting off the power supply of the distribution box), thereby further ensuring the safety of electricity use.

[0053] In other embodiments, the controller 320 is used to output a trigger signal to the leakage protection circuit 100 to trigger the leakage protection circuit 100 to disconnect when the ratio of the first difference to the average value of the first voltage detected in the preset time period before the current moment is greater than the first preset ratio threshold, and / or the ratio of the second difference to the average value of the second voltage detected in the preset time period before the current moment is greater than the second preset ratio threshold, and / or the third difference to the average value of the third voltage detected in the preset time period before the current moment is greater than the third preset ratio threshold. In this embodiment, some of the first preset ratio threshold, the second preset ratio threshold, and the third preset ratio threshold are not equal. It can be understood that the size of the first preset ratio threshold, the second preset ratio threshold, and the third preset ratio threshold can be set as needed.

[0054] The size of the preset time period can also be set as needed, for example, the size of the preset time period can be 1 second, or other. For example, the controller 320 samples once every 1 millisecond to obtain the first voltage, the second voltage and the third voltage, and calculates the average of the data sampled in the previous second every second.

[0055] In certain embodiments, see Figure 3 The signal detection circuit 310 includes comparators 311, and the number of the comparators 311 is at least three.

[0056] In this embodiment, the non-inverting input terminal of one of the at least three comparators 311 is used to connect the common ground point and one of the local ground starting points 210, and the inverting input terminal is used to connect the common ground point and the other of the local ground starting points 210; the non-inverting input terminal of one of the at least three comparators 311 is used to connect the common ground point and one of the local ground end points 220, and the inverting input terminal is used to connect the common ground point and the other of the local ground end points 220; and the non-inverting input terminal of one of the at least three comparators 311 is used to connect the local ground starting point 210 and one of the local ground end points 220, and the inverting input terminal is used to connect the local ground starting point 210 and the other of the local ground end points 220.

[0057] For example, please see again Figure 3 In some embodiments, the number of comparators 311 is 6, including a first comparator, a second comparator, a third comparator, a fourth comparator, a fifth comparator and a sixth comparator. Among them, the non-inverting input terminal of the first comparator is used to connect to the common ground point, and the inverting input terminal is used to connect to the local ground line starting point 210; the non-inverting input terminal of the second comparator is used to connect to the common ground point, and the inverting input terminal is used to connect to the local ground line end point 220; the non-inverting input terminal of the third comparator is used to connect to the local ground line starting point 210, and the inverting input terminal is used to connect to the local ground line end point 220; the non-inverting input terminal of the fourth comparator is used to connect to the local ground line starting point 210, and the inverting input terminal is used to connect to the common ground point; the non-inverting input terminal of the fifth comparator is used to connect to the local ground line end point 220, and the inverting input terminal is used to connect to the common ground point; the non-inverting input terminal of the sixth comparator is used to connect to the local ground line end point 220, and the inverting input terminal is used to connect to the local ground line starting point 210. In this embodiment, the common ground point, the local ground starting point 210 and the local ground end point 220 are combined in pairs and input into a comparator 311. Since the voltage level of the common ground point, the local ground starting point 210 and the local ground end point 220 in the pairwise combination is uncertain, the positive and negative directions are swapped and combined again.

[0058] For example, in some embodiments, the number of comparators 311 is 3, including a seventh comparator, an eighth comparator, and a ninth comparator. The non-inverting input terminal of the seventh comparator is used to connect to a common ground point, and the inverting input terminal is used to connect to the local ground starting point 210, or the non-inverting input terminal of the seventh comparator is used to connect to the local ground starting point 210, and the inverting input terminal is used to connect to the common ground point. The non-inverting input terminal of the eighth comparator is used to connect to a common ground point, and the inverting input terminal is used to connect to the local ground end point 220, or the non-inverting input terminal of the eighth comparator is used to connect to the local ground end point 220, and the inverting input terminal is used to connect to the common ground point. The non-inverting input terminal of the ninth comparator is used to connect to the local ground starting point 210, and the inverting input terminal is used to connect to the local ground end point 220. Optionally, the non-inverting input terminal of one of the comparators 311, another comparator 311, or the ninth comparator is used to connect to the local ground end point 220, and the inverting input terminal is used to connect to the local ground starting point 210. This embodiment is applicable to the case where the voltages of the common ground point, the local ground line starting point 210 and the local ground line end point 220 are known. Specifically, the non-inverting input terminal of the seventh comparator is used to connect the larger voltage between the common ground point and the local ground line starting point 210, and the inverting input terminal is used to connect the smaller voltage between the common ground point and the local ground line starting point 210. The non-inverting input terminal of the eighth comparator is used to connect the larger voltage between the common ground point and the local ground line end point 220, and the inverting input terminal is used to connect the smaller voltage between the common ground point and the local ground line end point 220. The non-inverting input terminal of the ninth comparator is used to connect the larger voltage between the local ground line starting point 210 and the local ground line end point 220, and the inverting input terminal is used to connect the smaller voltage between the local ground line starting point 210 and the local ground line end point 220.

[0059] It is understandable that the number of the comparators 311 may also be other numerical values ​​greater than 3. In addition, the embodiment of the present application does not specifically limit the type of the comparator 311. Optionally, the comparator 311 is a differential amplifier.

[0060] Optionally, see again Figure 3, the non-inverting input terminal of one of the at least three comparators 311 is connected to the common ground point and one of the local ground starting points 210 via the first resistor R1, and the inverting input terminal is connected to the common ground point and the other of the local ground starting points 210 via the first resistor R1; the non-inverting input terminal of one of the at least three comparators 311 is connected to the common ground point and one of the local ground end points 220 via the first resistor R1, and the inverting input terminal is connected to the common ground point and the other of the local ground end points 220 via the first resistor R1; and the non-inverting input terminal of one of the at least three comparators 311 is connected to the local ground starting point 210 and one of the local ground end points 220 via the first resistor R1, and the inverting input terminal is connected to the local ground starting point 210 and the other of the local ground end points 220 via the first resistor R1.

[0061] Further, please see again Figure 3 A second resistor R2 is also connected in series between the non-inverting input terminal and the inverting input terminal of each comparator 311.

[0062] The resistance values ​​of the first resistor R1 and the second resistor R2 can be selected as needed. For example, the resistance value of the first resistor R1 is 100 megohms, and the resistance value of the second resistor R2 is 1 megohm.

[0063] Optionally, the controller 320 includes a single-chip microcomputer, such as an ARM (Advanced RISC Machines, RISC microprocessor), an AVR (RISC reduced instruction set high-speed 8-bit single-chip microcomputer) or the like; of course, the controller 320 may also include a dedicated chip or other device capable of processing and transmitting data, such as an ASIC (Application Specific Integrated Circuit, application-specific integrated circuit) chip, or a programmable device such as an FPGA (Field-Programmable Gate Array, field programmable gate array), a CPLD (Complex Programmable Logic Device, complex programmable logic device) or the like.

[0064] See also Figure 2 The leakage protection circuit 100 may include a leakage protector 110 and a leakage switch 120 connected in series, wherein the leakage protector 110 is used to access the live wire and the neutral wire of the mains, and the leakage protection switch is electrically connected to the controller 320 of the protection device 300 .

[0065] Please see again Figure 2The protection device 300 may also include a test button 330, which is electrically connected between the local ground starting point 210 and the local ground end point 220 to disconnect or connect the electrical connection between the local ground starting point 210 and the local ground end point 220; and the test button 330 is also electrically connected to the leakage switch 120. When the test button 330 is disconnected, the electrical connection between the local ground starting point 210 and the local ground end point 220 is disconnected, and the controller 320 is used to obtain the state of the leakage protection circuit 100 (i.e., the state of the leakage switch 120) to determine whether the leakage protection circuit 100 is turned on. The test button 330 can be used to check whether the test button 330 triggers the leakage protection circuit 100 to turn off when the electrical connection between the local ground starting point 210 and the local ground end point 220 is disconnected, as a normal check.

[0066] Please combine Figure 2 and Figure 4A The protection device 300 may also include a load 340, the ground wire of the load 340 is connected in series with the local ground wire starting point 210 or the end point of the local ground wire 200, so that if the ground wire of any load 340 is disconnected, it can be immediately discovered. That is, the ground wire of each load 340 is connected in series from the local ground wire starting point 210. Figure 4B (T-connection) and Figure 4C (Split-line connection) is an incorrect connection method. Figures 4A-4C The load 340 in the embodiment of the present application may include any load, and may also include a connector such as a socket that can connect any load.

[0067] In the embodiments of the present invention, see Figure 2 One end of the test button 330 is connected to one end of the ground wire of the load 340 to realize the connection between the test button 330 and the local ground wire starting point 210; the other end of the test button 330 is connected to the other end of the ground wire of the load 340 to realize the connection between the test button 330 and the local ground wire end point 220.

[0068] The present invention also provides a distribution box, see Figure 2 The distribution box includes a leakage protection circuit 100, a local ground wire 200 and the protection device 300 of the above embodiment. The leakage protection circuit 100 is used to access the live wire and the neutral wire of the mains to access the power supply. The local ground wire 200 is connected in series with the public ground wire.

[0069] Optionally, the public ground wire is connected in series with the local ground wire 200 through a water-immersion non-touch protector 400. Figure 2 The common ground wire is connected to one end of the submersible non-touch protector 400 , and the local ground wire starting point 210 is connected to the other end of the submersible non-touch protector 400 to realize the series connection between the common ground wire and the local ground wire 200 .

[0070] Please see again Figure 2 The leakage protection circuit 100 includes a leakage protector 110 and a leakage switch 120 connected in series, the leakage protector 110 is used to access the live wire and the neutral wire of the mains, and the leakage protection switch is electrically connected to the controller 320 of the protection device 300. The leakage switch 120 can be a leakage air switch or other types of leakage switches.

[0071] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A protection device for a distribution box, the distribution box comprising a leakage protection circuit (100) and a local ground wire (200), the leakage protection circuit (100) being used to access the live wire and the neutral wire of the mains to access the power supply, the local ground wire (200) being connected in series with the public ground wire; characterized in that: The protection device (300) comprises: A signal detection circuit (310) for detecting a first voltage between a common ground point and a local ground start point (210), a second voltage between the common ground point and a local ground end point (220), and a third voltage between the local ground start point and the local ground end point (220); and A controller (320) electrically connected to the signal detection circuit (310) and the leakage protection circuit (100) respectively; When any one of the ratio of the first difference to the average value of the first voltage detected and obtained within a preset time period before the current moment, the ratio of the second difference to the average value of the second voltage detected and obtained within the preset time period before the current moment, and the ratio of the third difference to the average value of the third voltage detected and obtained within the preset time period before the current moment is greater than a preset ratio threshold, the controller (320) outputs a trigger signal to the leakage protection circuit (100) to trigger the leakage protection circuit (100) to disconnect; Wherein, the first difference is the difference between the first voltage detected at the current moment and the average value of the first voltage detected within a preset time period before the current moment; The second difference is a difference between the second voltage detected at the current moment and an average value of the second voltage detected within a preset time period before the current moment; The third difference is a difference between the third voltage detected at the current moment and an average value of the third voltage detected within a preset time period before the current moment.

2. The protection device according to claim 1, characterized in that: The signal detection circuit (310) comprises at least three comparators (311); A comparator (311) among at least three of the comparators (311) has a non-inverting input terminal for connecting the common ground point and one of the local ground line starting points (210), and an inverting input terminal for connecting the common ground point and the other of the local ground line starting points (210); A comparator (311) among at least three of the comparators (311) has a non-inverting input terminal for connecting the common ground point and one of the local ground line endpoints (220), and an inverting input terminal for connecting the common ground point and the other of the local ground line endpoints (220); The same-phase input terminal of one comparator (311) among at least three comparators (311) is used to connect the local ground starting point (210) and one of the local ground end points (220), and the inverting input terminal is used to connect the local ground starting point (210) and the other of the local ground end points (220).

3. The protection device according to claim 2, characterized in that: The number of the comparators (311) is 6, including a first comparator, a second comparator, a third comparator, a fourth comparator, a fifth comparator and a sixth comparator; Wherein, the non-inverting input terminal of the first comparator is used to connect to the common ground point, and the inverting input terminal is used to connect to the starting point of the local ground line (210); The non-inverting input terminal of the second comparator is used to connect to the common ground point, and the inverting input terminal is used to connect to the local ground terminal (220); The non-inverting input terminal of the third comparator is used to connect to the local ground line starting point (210), and the inverting input terminal is used to connect to the local ground line ending point (220); The non-inverting input terminal of the fourth comparator is used to connect to the local ground line starting point (210), and the inverting input terminal is used to connect to the common ground point; The non-inverting input terminal of the fifth comparator is used to connect to the local ground line terminal (220), and the inverting input terminal is used to connect to the common ground point; The non-inverting input terminal of the sixth comparator is used to connect to the local ground line end point (220), and the inverting input terminal is used to connect to the local ground line start point (210).

4. The protection device according to claim 1, characterized in that: The controller (320) includes a single chip microcomputer.

5. The protection device according to claim 1, characterized in that: The protection device (300) further comprises a test button (330) electrically connected between the local ground line starting point (210) and the local ground line ending point (220) to disconnect or connect the electrical connection between the local ground line starting point (210) and the local ground line ending point (220); When the test button (330) is disconnected, the electrical connection between the local ground line starting point (210) and the local ground line end point (220) is disconnected, and the controller (320) is used to obtain the state of the leakage protection circuit (100) to determine whether the leakage protection circuit (100) is turned on.

6. The protection device according to claim 1, characterized in that: The protection device (300) further comprises a load (340), wherein a ground line of the load (340) is connected in series with a starting point (210) of the local ground line or an end point of the local ground line.

7. A distribution box, characterized in that: The distribution box comprises: The leakage protection circuit (100) is used to connect to the live wire and the neutral wire of the mains to connect to the power supply; A local ground line (200) connected in series with the public ground line; and The protection device (300) according to any one of claims 1 to 6.

8. The distribution box according to claim 7, characterized in that: The common ground wire and the local ground wire (200) are connected in series via a water-immersion non-touch protector (400).

9. The distribution box according to claim 7, characterized in that: The leakage protection circuit (100) comprises a leakage protector (110) and a leakage switch (120) connected in series, the leakage protector (110) being used to access the live wire and the neutral wire of the mains, and the leakage switch being electrically connected to a controller (320) of the protection device (300).

10. The distribution box according to claim 9, characterized in that: The leakage switch (120) is a leakage air switch.

Images