Circuit board of an electrical connection device and electrical connection device

Abstract

The utility model discloses a kind of circuit board and electric connection equipment of electric connection equipment, electric connection equipment includes power cord, and the detection protection device electrically connected with power cord;Power cord includes first current-carrying wire, second current-carrying wire and the shielding conductor being set to the outer side of first current-carrying wire and second current-carrying wire;Detection protection device includes power module, self-checking path module, response processing module;Circuit board includes lower area and upper area;Power module is set to lower area;Self-checking path module and response processing module are set to upper area.It can be better to separate high-voltage part and low-voltage part in detection protection device, and self-checking path module and response processing module between upper area can be directly realized electric connection and shorten wiring, conducive to improving the space utilization of circuit board, reduce the size of circuit board, reduce wiring difficulty, reduce the interference received by electric signal transmitted on circuit board.

Description

Technical Field

[0001] This utility model relates to the field of circuit board technology, and in particular to a circuit board and electrical connection device for electrical connection equipment. Background Technology

[0002] A leakage circuit breaker (LCDI) is a power connection device for electrical appliances. It detects leakage current in the power supply line via a leakage current detection lead and disconnects the power supply to the appliance when a certain leakage current is detected, ensuring safe operation. In recent years, LCDIs have not only needed to detect leakage current in the power supply line via the leakage current detection lead, but also have higher safety detection requirements, such as detecting whether the leakage current detection lead is open-circuited.

[0003] Currently, with the increasing demand for safety testing of power cord detection and protection devices, the number of components in the circuit modules included in these devices is also increasing. As a result, the circuit board layout of electrical connection equipment is facing more and more challenges, such as difficulties in circuit board routing, the need for winding, the susceptibility of electrical signals transmitted on the circuit board to interference, and the need for larger board sizes. Utility Model Content

[0004] The purpose of this utility model is to at least solve one of the technical problems existing in the prior art, and to provide a circuit board and electrical connection device for an electrical connection device, which can improve the space utilization of the circuit board, reduce the size of the circuit board, reduce the difficulty of wiring, and reduce the interference of electrical signals transmitted on the circuit board.

[0005] In a first aspect, the present invention provides a circuit board for an electrical connection device, the electrical connection device including a power cord and a detection and protection device electrically connected to the power cord; The power line includes a first current-carrying line, a second current-carrying line, and a shielding conductor disposed outside the first current-carrying line and the second current-carrying line; The detection and protection device includes a power module, a self-test path module, and a response processing module. The circuit board includes a lower region and an upper region; The power module is located in the lower region and is used to output a DC detection voltage. The self-test path module and the response processing module are located in the upper region; the self-test path module is electrically connected to the shielding conductor and the output terminal of the power module respectively; the response processing module is electrically connected to the first current-carrying line, the second current-carrying line and the self-test path module respectively, and is used to disconnect the power connection between the input terminal and the output terminal of the power line when the shielding conductor is open-circuited or when the shielding conductor detects a leakage signal.

[0006] The circuit board of the electrical connection device provided according to the embodiments of this utility model has at least the following beneficial effects: Since the detection and protection device in the electrical connection device needs to detect both the leakage current of the current-carrying line through the shielded conductor and the open circuit of the shielded conductor of the current-carrying line, it is necessary to construct a complex detection path. Therefore, the detection and protection device needs to be equipped with a number of modules such as a power module, a self-test path module, and a response processing module. The circuit board places the power module in the lower area and the self-test path module and the response processing module in the upper area, which can better separate the high-voltage part and the low-voltage part in the detection and protection device. The self-test path module and the response processing module in the upper area can be directly electrically connected to shorten the wiring, which is beneficial to improve the space utilization of the circuit board, reduce the size of the circuit board, reduce the wiring difficulty, and reduce the interference of the electrical signals transmitted on the circuit board.

[0007] The circuit board provided according to some embodiments of the present invention further includes a power failure detection module disposed in the upper region. The power failure detection module is used to trigger the response processing module to disconnect the power connection between the input end and the output end of the power line when the DC detection voltage output by the power module fails.

[0008] According to some embodiments of the present invention, the power failure detection module includes a first switching transistor, a voltage divider injection module located to the right of the first switching transistor and electrically connected to the first switching transistor, and a voltage divider trigger module located to the left of the first switching transistor and electrically connected to the first switching transistor. The voltage divider injection module is used to provide a second trip trigger signal to the response processing module when the DC detection voltage output by the power module fails. The voltage divider trigger module is used to control the first switch to turn on when the DC detection voltage output by the power module is valid, so that the voltage divider injection module cannot provide the second trip trigger signal to the response processing module.

[0009] According to some embodiments of the present invention, the power module includes a second electrolytic capacitor, a first through hole for welding the anode of the second electrolytic capacitor is provided in the lower region, and a second through hole is provided in the upper region adjacent to and electrically connected to the voltage divider trigger module; a first trace connecting the first through hole and the second through hole is provided on the back of the circuit board.

[0010] According to some embodiments of the present invention, the circuit board of the voltage divider injection module includes a first resistor, a second diode, and a first diode and a second resistor connected in sequence. The upper region is provided with a first pad for soldering the first current-carrying line; one end of the first resistor is adjacent to and electrically connected to the first pad. The upper region is further provided with a third through hole adjacent to and electrically connected to the other end of the first resistor, a fourth through hole adjacent to and electrically connected to the anode of the second diode, a fifth through hole adjacent to and electrically connected to the cathode of the second diode, and a sixth through hole adjacent to and electrically connected to the anode of the first diode; the back side of the upper region is provided with a second trace connecting the third through hole and the fourth through hole, and a third trace connecting the fifth through hole and the sixth through hole; The second resistor is adjacent to and electrically connected to the first diode; the connection point between the first diode and the second resistor is adjacent to and electrically connected to the response processing module. The fifth through hole is also adjacent to and electrically connected to the control pin of the first switching transistor.

[0011] According to some embodiments of the present invention, the circuit board of the voltage divider trigger module includes a third resistor and a fourth resistor arranged adjacent to each other; One end of the third resistor is adjacent to and electrically connected to the second through hole; The fourth resistor is adjacent to the first switch transistor; the upper region is also provided with a second pad for soldering the second current-carrying line; one end of the fourth resistor, one switch pin of the first switch transistor, and the second pad are electrically connected through a fourth trace provided on the front side of the upper region; the other end of the third resistor, the other end of the fourth resistor, and the other switch pin of the first switch transistor are electrically connected.

[0012] According to some embodiments of the present invention, the voltage divider injection module further includes a first capacitor and a second capacitor. The first capacitor is adjacent to and connected in parallel with the second resistor; The second capacitor is located between the first switch and the second diode; one end of the second capacitor is adjacent to and electrically connected to the cathode of the second diode, and the other end is located in the fourth trace.

[0013] According to some embodiments of the present invention, the self-test path module of the circuit board includes a first self-test unit and a second self-test unit. The first self-test unit is located to the left of the second through hole and is electrically connected to the second through hole; The second self-test unit is located above the first self-test unit and is electrically connected to the first self-test unit; The response processing module includes a fault signal processing module, which is located to the right of the first self-test unit and below the second self-test unit. The fault signal processing module is used to acquire the open circuit signal generated when the shielding conductor is open and the leakage current signal detected by the shielding conductor, and output a first tripping trigger signal in response to the open circuit signal or the leakage current signal.

[0014] According to some embodiments of the present invention, the circuit board includes a first shielding conductor covering the first current-carrying line and a second shielding conductor covering the second current-carrying line; the first shielding conductor includes a first end near the input end of the power line and a second end near the output end of the power line; the second shielding conductor includes a third end near the input end of the power line and a fourth end near the output end of the power line. The upper region is also provided with a seventh through hole that is adjacent to and electrically connected to the second self-test unit; The lower region is also provided with an eighth through hole for welding the first end and the third end; The back of the circuit board is also provided with a fifth trace connecting the seventh through hole and the eighth through hole.

[0015] According to some embodiments of the present invention, the circuit board provided by the circuit board further includes a trigger module, which is configured to disconnect the power connection between the input and output terminals of the power line via a switch module in response to receiving the first trip trigger signal. The triggering module includes a trip coil, a silicon controlled rectifier, and a sixth diode connected in sequence. The trip coil is used to generate electromagnetic force to drive the switching module to disconnect the power connection. The upper region is also provided with a ninth through hole and a tenth through hole for welding the trip coil. The ninth through hole is adjacent to and electrically connected to the first pad. The thyristor is adjacent to the voltage divider injection module and is electrically connected to the connection point of the first diode and the second resistor. The upper region is also provided with an eleventh through hole that is adjacent to and electrically connected to the thyristor, and the back side of the upper region is also provided with a sixth trace that connects the tenth through hole and the eleventh through hole; The cathode of the sixth diode is adjacent to and electrically connected to the second pad.

[0016] According to some embodiments of the present invention, the circuit board provided includes a fault signal processing module comprising a second transistor and a third transistor arranged adjacent to each other. The detection and protection device further includes a 22nd resistor; one end of the 22nd resistor is adjacent to and electrically connected to the control pin of the thyristor, and the other end is electrically connected to the collector of the second transistor and the collector of the third transistor through a 7th trace on the front side of the upper region.

[0017] According to some embodiments of the present invention, a circuit board is provided below the seventh trace, and an eighth trace connecting the twelfth trace and the anode of the sixth diode is also provided on the front side of the upper region. A thirteenth through hole is provided above the seventh trace, and a ninth trace connecting the thirteenth through hole, the second resistor and the thyristor is also provided on the front side of the upper region. The back of the upper region is also provided with a tenth trace connecting the twelfth through hole and the thirteenth through hole.

[0018] According to some embodiments of the present invention, the circuit board provided by the first self-test unit includes a fifth resistor, a sixth resistor, and a third diode arranged sequentially from top to bottom; The anode of the third diode is adjacent to and electrically connected to the second through hole; The upper region is also provided with a fourteenth through hole adjacent to and electrically connected to the cathode of the third diode, and a fifteenth through hole adjacent to and electrically connected to the upper end of the fifth resistor. The back side of the upper region is also provided with an eleventh trace connecting the fourteenth through hole and the fifteenth through hole. The lower end of the fifth resistor, the upper end of the sixth resistor, the base of the second transistor, and the emitter of the third transistor are electrically connected through a twelfth trace disposed on the front side of the upper region. The lower end of the sixth resistor is located in the eighth trace.

[0019] According to some embodiments of the present invention, the circuit board provided by the second self-test unit includes a seventh resistor and an eighth resistor; One end of the seventh resistor is adjacent to and electrically connected to the upper end of the fifth resistor; The other end of the seventh resistor, one end of the eighth resistor, and the seventh through hole are electrically connected by the thirteenth trace provided on the front of the upper region. The other end of the eighth resistor is adjacent to and electrically connected to the emitter of the second transistor and the base of the third transistor.

[0020] According to some embodiments of the present invention, the circuit board provided by the detection and protection device further includes a test module, which includes a twenty-first resistor and a test switch. The upper region is provided with a first contact area and a second contact area for the two ends of the test switch to be pressed; One end of the 21st resistor is electrically connected to the cathode of the 3rd diode through the 14th trace disposed on the front side of the upper region, and the other end is adjacent to and electrically connected to the first contact area; The upper region is also provided with a sixteenth through hole that is adjacent to and electrically connected to the second contact area, and the back side of the upper region is provided with a fifteenth trace that is electrically connected to the sixteenth through hole and the fifth trace.

[0021] According to some embodiments of the present invention, the circuit board of the voltage divider trigger module includes a third resistor and a fourth resistor arranged adjacent to each other; One end of the third resistor is adjacent to and electrically connected to the second through hole; The fourth resistor is adjacent to the first switching transistor; one end of the fourth resistor and one switching pin of the first switching transistor are electrically connected to the anode of the sixth diode through the eighth trace; The other end of the third resistor, the other end of the fourth resistor, and the other switch pin of the first switch are electrically connected.

[0022] According to some embodiments of the present invention, the circuit board provided by the present invention further includes an indicator module located above the ninth trace, the indicator module including an eleventh resistor and a light-emitting diode; The upper region is also provided with a seventeenth through hole that is adjacent to and electrically connected to one end of the eleventh resistor; the back side of the upper region is also provided with a sixteenth trace that is electrically connected to the seventeenth through hole and the second through hole; The other end of the eleventh resistor is adjacent to and electrically connected to the anode of the light-emitting diode; The upper region also has a seventeenth trace electrically connected to the cathode of the light-emitting diode and the ninth trace on its front side.

[0023] According to some embodiments of the present invention, the circuit board provided by the circuit board further includes a first varistor; The upper region is also provided with an eighteenth and a nineteenth through hole for welding the first varistor; The eighteenth through hole is located on the sixth routing line; The nineteenth through hole is electrically connected to the eighth trace via the eighteenth trace located in the upper region.

[0024] According to some embodiments of the present invention, the power module includes a second varistor; the detection and protection device further includes a fuse disposed in the upper region. One end of the fuse is adjacent to and electrically connected to the first pad; The upper region is also provided with a twentieth through hole that is adjacent to and electrically connected to the other end of the fuse. The lower region is also provided with a 21st through hole and a 22nd through hole for welding the second varistor; The back of the circuit board is also provided with a nineteenth trace connecting the twentieth through hole and the twentieth through hole; The front side of the circuit board is also provided with a twentieth trace connecting the twentieth through hole and the second pad.

[0025] Secondly, this utility model provides an electrical connection device, including a circuit board, a power cord, and a detection and protection device disposed on the circuit board and connected to the power cord as described in the first aspect embodiment above.

[0026] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0027] The accompanying drawings are provided to further understand the technical solution of this utility model and constitute a part of the specification. They are used together with the embodiments of this utility model to explain the technical solution of this utility model, and do not constitute a limitation on the technical solution of this utility model.

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a circuit diagram of a portion of the circuit modules of the detection and protection device provided in this embodiment of the utility model; Figure 2 This is a circuit diagram of the power supply module of the detection and protection device provided in this embodiment of the utility model; Figure 3 This is a schematic diagram of the front layout of the circuit board provided in an embodiment of the present utility model; Figure 4 This is a schematic diagram of the back layout of the circuit board provided in an embodiment of the present utility model; Figure 5 This is a circuit diagram of a portion of the circuit modules of the detection and protection device provided in another embodiment of this utility model; Figure 6This is a corresponding embodiment of the present utility model. Figure 5 The circuit schematic diagram shown is a front view of the circuit board layout. Figure 7 This is a schematic diagram of the overall structure of the electrical connection device provided in this embodiment of the utility model. Detailed Implementation

[0029] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0030] In the description of the embodiments of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the stated number, while "above," "below," "within," etc. are understood to include the stated number. "At least one" refers to one or more, and "at least one of the following" and similar expressions refer to any combination of these items, including any combination of single or multiple items. If "first," "second," etc., are used in the description, they are only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of the indicated technical features.

[0031] It should be noted that the terms "setting," "installing," and "connecting" in the embodiments of this utility model should be interpreted broadly. Those skilled in the art can reasonably determine the specific meaning of the above terms in the embodiments of this utility model in conjunction with the specific content of the technical solution. For example, the term "connection" can be a mechanical connection, an electrical connection, or a connection that allows for mutual communication; it can be a direct connection or an indirect connection through an intermediate medium.

[0032] It should be noted that the technical features involved in the various embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0033] A leakage circuit breaker (LCDI) is a power connection device for electrical appliances. It detects leakage current in the power supply line via a leakage current detection lead and disconnects the power supply to the appliance when a certain leakage current is detected, ensuring safe operation. In recent years, LCDIs have not only needed to detect leakage current in the power supply line via the leakage current detection lead, but also have higher safety detection requirements, such as detecting whether the leakage current detection lead is open-circuited.

[0034] Currently, with the increasing demand for safety testing of power cord detection and protection devices, the number of components in the circuit modules included in these devices is also increasing. As a result, the circuit board layout of electrical connection equipment is facing more and more challenges, such as difficulties in circuit board routing, the need for winding, the susceptibility of electrical signals transmitted on the circuit board to interference, and the need for larger board sizes.

[0035] Based on this, the present invention provides a circuit board and electrical connection device for an electrical connection device, which can improve the space utilization of the circuit board, reduce the size of the circuit board, reduce the difficulty of wiring, and reduce the interference of electrical signals transmitted on the circuit board.

[0036] The embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0037] Figure 1 This is a circuit diagram of a portion of the circuit modules of the detection and protection device provided in this embodiment of the utility model; Figure 2 This is a circuit diagram of the power supply module of the detection and protection device provided in this embodiment of the utility model.

[0038] Reference Figure 1 The power cord includes a first current-carrying line 110, a second current-carrying line 120, and a shielding conductor disposed outside the first current-carrying line 110 and the second current-carrying line 120; exemplarily, the shielding conductor includes a first shielding conductor 130 covering the first current-carrying line 110 and a second shielding conductor 140 covering the second current-carrying line 120.

[0039] It is understandable that when a power supply line supplies power to electrical equipment using two-phase AC power, it can be one of the following two scenarios: the first current-carrying wire 110 is the live wire L, and the second current-carrying wire 120 is the neutral wire N; or the first current-carrying wire 110 is the neutral wire N, and the second current-carrying wire 120 is the live wire L. When a power supply line supplies power to electrical equipment using three-phase AC power, it can be one of the following three scenarios: the first current-carrying wire 110 is the live wire L1, and the second current-carrying wire 120 is the neutral wire N; the first current-carrying wire 110 is the neutral wire N, and the second current-carrying wire 120 is the live wire L1; or the first current-carrying wire 110 is the live wire L1, and the second current-carrying wire 120 is the live wire L2. Below, we will use... Figure 1 The following example illustrates the situation where the first current-carrying line 110 is the live wire L and the second current-carrying line 120 is the neutral wire N. The other cases can be understood in the same way.

[0040] Continue to refer to Figure 1The first shielding conductor 130 is used to collect the leakage current signal of the first current-carrying line 110, and the second shielding conductor 140 is used to collect the leakage current signal of the second current-carrying line 120. The first shielding conductor 130 includes a first end a near the input end of the power line and a second end b near the output end of the power line. The second shielding conductor 140 includes a fourth end d near the input end and a fifth end e near the output end.

[0041] Reference Figure 1 and Figure 2 The detection and protection device includes a power supply module 200, a self-test path module 300, a response processing module, and a power failure detection module 500, wherein: The power module 200 is electrically connected to the first current-carrying line 110 and the second current-carrying line 120 respectively, and is used to output a DC detection voltage of +18V; for example, refer to Figure 2 As shown, Figure 2 The diagram below shows a specific circuit schematic of a power module 200 provided in one embodiment of this utility model. It is understood that the DC detection voltage output by the power module 200 is not limited to +18V, but can be other voltage levels, such as +5V, +12V, +24V, etc.

[0042] The self-test path module 300 is electrically connected to the first shielding conductor 130, the second shielding conductor 140, and the output terminal of the power module 200, respectively. The response processing module is electrically connected to the first current-carrying line 110, the second current-carrying line 120, and the self-test path module 300, respectively, and is used to disconnect the power connection between the input and output terminals of the power line in the event that the first shielding conductor 130 is open, the second shielding conductor 140 is open, the first shielding conductor 130 detects a leakage signal and / or the second shielding conductor 140 detects a leakage signal. The power failure detection module 500 is electrically connected to the response processing module and the output terminal of the power module 200, respectively. It is used to trigger the response processing module to disconnect the power connection between the input and output terminals of the power line when the DC detection voltage +18V output by the power module 200 fails.

[0043] Figure 3 This is a schematic diagram of the front layout of the circuit board provided in an embodiment of the present utility model; Figure 4 This is a schematic diagram of the back layout of the circuit board provided in this embodiment of the utility model.

[0044] Reference Figure 3 and Figure 4 The circuit board of the electrical connection device provided in the first aspect embodiment of this utility model includes a lower region and an upper region; the power module 200 is disposed in the lower region; the self-test path module 300, the response processing module and the power failure detection module 500 are all disposed in the upper region.

[0045] According to the circuit board of the electrical connection device provided in the embodiment of this utility model, since the detection and protection device in the electrical connection device needs to detect both the leakage current of the current-carrying line through the shielded conductor and the open circuit of the shielded conductor of the current-carrying line, a complex detection path needs to be constructed. Therefore, the detection and protection device needs to be equipped with a number of modules such as a power module 200, a self-test path module 300, a response processing module, and a power failure detection module 500. The circuit board places the power module 200 in the lower area and the self-test path module 300, the response processing module, and the power failure detection module 500 in the upper area, which can better separate the high-voltage part and the low-voltage part in the detection and protection device. The self-test path module 300, the response processing module, and the power failure detection module 500 in the upper area can be directly electrically connected, thus shortening the wiring. This is beneficial to improving the space utilization of the circuit board, reducing the size of the circuit board, reducing the wiring difficulty, and reducing the interference of the electrical signals transmitted on the circuit board.

[0046] Understandably, the detection and protection device also includes a switch module 1000 for controlling the power connection between the input and output terminals of the power cord. (Refer to...) Figure 1 As shown, the switch module 1000 is provided with switch terminals on the first current-carrying line 110 and the second current-carrying line 120. When the switch terminals of the switch module 1000 are closed, the power connection between the input end and the output end of the power line is made on; when the switch terminals of the switch module 1000 are open, the power connection between the input end and the output end of the power line is disconnected.

[0047] In the power cord detection and protection device provided in this embodiment of the utility model, the first shielding conductor 130 covers the first current-carrying line 110, thereby enabling the collection of leakage signals from the first current-carrying line 110. The second shielding conductor 140 covers the second current-carrying line 120, thereby enabling the collection of leakage signals from the second current-carrying line 120. Based on this, under the action of the DC detection voltage +18V provided by the power module 200, the self-test path module 300, together with the first shielding conductor 130 and the second shielding conductor 140, forms an open-circuit self-test path. In the event of leakage or open circuit, the power connection between the input and output terminals of the power cord is disconnected by the response processing module, ensuring the power supply safety of the power cord. A power failure detection module 500 is also provided to detect the validity of the DC detection voltage +18V output by the power module 200. In the event of failure of the DC detection voltage +18V output by the power module 200, the response processing module is triggered to disconnect the power connection between the input and output terminals of the power cord, improving the reliability of the detection and protection device.

[0048] Reference Figure 2In some embodiments of the detection and protection device provided by this utility model, the power module 200 includes a second varistor ZR2, a twelfth resistor R12, a seventh diode D7, an eighth diode D8, a first electrolytic capacitor E1, a thirteenth resistor R13, a fifth capacitor C5, a ninth diode D9, a fourteenth resistor R14, a transformer TR1, a voltage regulator chip U1, a tenth diode D10, an eleventh diode D11, a fifteenth resistor R15, a sixth capacitor C6, a seventh capacitor C7, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a second electrolytic capacitor E2, and an eighth capacitor C8; wherein, the transformer TR1 includes a primary winding, an output winding, and a feedback winding. Additionally, the detection and protection device also includes a fuse FUSE.

[0049] Specifically, the first current-carrying line 110 is connected to one end of the fuse FUSE, and the other end of the fuse FUSE is connected to one end of the second varistor ZR2 and one end of the twelfth resistor R12; the other end of the twelfth resistor R12 is connected to the anode of the seventh diode D7, the cathode of the seventh diode D7 is connected to the anode of the eighth diode D8, the cathode of the eighth diode D8 is connected to one end of the first electrolytic capacitor E1, one end of the thirteenth resistor R13, one end of the fifth capacitor C5, and one end of the primary winding of the transformer TR1; the other end of the thirteenth resistor R13 is connected together with the other end of the fifth capacitor C5 and connected to the cathode of the ninth diode D9, the anode of the ninth diode D9 is connected to one end of the fourteenth resistor R14, and the other end of the fourteenth resistor R14 and the other end of the primary winding of the transformer TR1 are both connected to the drain terminal of the voltage regulating chip U1; One end of the output winding of transformer TR1 is connected to the anode of the tenth diode D10; the cathode of the tenth diode D10 is connected to one end of the second electrolytic capacitor E2 and one end of the eighth capacitor C8. One end of the feedback winding of transformer TR1 is connected to one end of the fifteenth resistor R15, one end of the sixteenth resistor R16, and one end of the seventeenth resistor R17; the other end of the fifteenth resistor R15 is connected to the anode of the eleventh diode D11, and the cathode of the eleventh diode D11 is connected to the VCC terminal of voltage regulator chip U1, one end of the sixth capacitor C6, and one end of the seventh capacitor C7; the other ends of the sixth capacitor C6 and the seventh capacitor C7 are connected to the GND terminal of voltage regulator chip U1 and grounded; the other ends of the sixteenth resistor R16 and the seventeenth resistor R17 are connected to the FB terminal of voltage regulator chip U1 and to one end of the eighteenth resistor R18; one end of the nineteenth resistor R19 is connected to the ISEN terminal of voltage regulator chip U1. The second current-carrying line 120 connects to the other end of the second varistor ZR2, the other end of the first electrolytic capacitor E1, the other end of the nineteenth resistor R19, the other end of the eighteenth resistor R18, the other end of the feedback winding of transformer TR1, the other end of the output winding of transformer TR1, the other end of the second electrolytic capacitor E2, and the other end of the eighth capacitor C8.

[0050] In the power module 200 provided in this embodiment, the input terminal, output terminal, and feedback terminal are completely separated by a transformer TR1. Energy transfer is achieved through coupling, and there is no electrical connection between the output terminal and the feedback terminal. Specifically, the layout of the various components in the power module 200 on the circuit board is as follows: Figure 3 and Figure 4 The lower region is shown in the image.

[0051] Reference Figure 1 The power failure detection module 500 includes a first switching transistor Q1, a voltage divider injection module 510 electrically connected between the first current-carrying line 110 and the second current-carrying line 120, and a voltage divider trigger module 520 electrically connected between the output terminal of the power module 200 and the second current-carrying line 120. The voltage divider injection module 510 is also electrically connected to the response processing module and is used to provide a second trip trigger signal to the response processing module when the DC detection voltage +18V output by the power module 200 fails. The two switching pins of the first switching transistor Q1 are electrically connected to the voltage divider injection module 510 and the second current-carrying line 120, respectively. The voltage divider trigger module 520 is electrically connected to the control pin of the first switching transistor Q1 so that when the DC detection voltage +18V output by the power module 200 is valid, it controls the first switching transistor Q1 to be turned on so that the voltage divider injection module 510 cannot provide the second trip trigger signal to the response processing module. When the +18V DC detection voltage output by the power module 200 is valid, the voltage divider trigger module 520 divides the voltage difference between the output terminal of the power module 200 and the second current-carrying line 120, and provides a first-level voltage signal to the control pin of the first switch Q1, causing the first switch Q1 to conduct. The voltage divider injection module 510 conducts to the second current-carrying line 120 through the first switch Q1, thus preventing it from providing the second trip trigger signal to the response processing module. When the +18V DC detection voltage output by the power module 200 fails, the voltage divider trigger module 520 provides a 0V low-level voltage signal to the control pin of the first switch Q1, causing the first switch Q1 to turn off. The voltage divider injection module 510 is directly electrically connected between the first current-carrying line 110 and the second current-carrying line 120, and provides the second trip trigger signal to the response processing module to trigger the response processing module to disconnect the power connection between the input and output terminals of the power line.

[0052] Reference Figure 3In some embodiments of the present invention, the voltage divider injection module 510 is located to the right of the first switching transistor Q1 and is electrically connected to the first switching transistor Q1; the voltage divider trigger module 520 is located to the left of the first switching transistor Q1 and is electrically connected to the first switching transistor Q1. In this embodiment, the first switch Q1 is adjacent to both the voltage divider injection module 510 and the voltage divider trigger module 520, which can be conveniently connected to the first switch Q1. This allows the voltage signals provided by the voltage divider injection module 510 and the voltage divider trigger module 520 to be transmitted to the first switch Q1 with a shorter trace.

[0053] Reference Figure 2 The power module 200 includes a second electrolytic capacitor E2, which serves as an output filter capacitor.

[0054] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the circuit board is provided with a first through hole E2-1 for welding the anode of the second electrolytic capacitor E2 in the lower region, and a second through hole +18V-1 adjacent to and electrically connected to the voltage divider trigger module 520 in the upper region; a first trace Z01 connecting the first through hole E2-1 and the second through hole +18V-1 is provided on the back of the circuit board.

[0055] In this embodiment, the DC detection voltage +18V output by the power module 200 in the lower region is transmitted to the voltage divider trigger module 520 in the upper region through the first trace Z01.

[0056] Reference Figure 1The voltage divider injection module 510 includes a first resistor R1, a second diode D2, a first diode D1 and a second resistor R2; the first current-carrying line 110, the first resistor R1, the second diode D2, the first diode D1, the second resistor R2 and the second current-carrying line 120 are electrically connected in sequence; the connection point between the second diode D2 and the first diode D1 is connected to the first switching transistor Q1; the connection point between the first diode D1 and the second resistor R2 is connected to the response processing module. When the first switch Q1 is turned off, ignoring the voltage drop between the second diode D2 and the first diode D1, the voltage difference between the first current-carrying line 110 and the second current-carrying line 120 is divided by the first resistor R1 and the second resistor R2 to obtain the second trip trigger signal. The second trip trigger signal is then output to the response processing module from the connection point of the first diode D1 and the second resistor R2. When the first switch Q1 is turned on, the connection point of the second diode D2 and the first diode D1 is connected to the second current-carrying line 120 through the first switch Q1, forming a conduction loop of the first current-carrying line 110, the first resistor R1, the second diode D2, the first switch Q1, and the second current-carrying line 120. At this time, the connection point of the first diode D1 and the second resistor R2 cannot output the second trip trigger signal to the response processing module. In addition, by setting a first diode D1 and a second diode D2 in the voltage divider injection module 510, the conduction loop from the first current-carrying line 110 through the first resistor R1 and the first switch Q1 to the second current-carrying line 120, and the conduction loop from the first current-carrying line 110 through the first resistor R1, the first diode D1 and the second resistor R2 to the second current-carrying line 120, are only implemented in the half-cycle when the voltage amplitude of the first current-carrying line 110 is greater than the voltage amplitude of the second current-carrying line 120, and are not conducted in the other half-cycle.

[0057] It should be noted that in some embodiments, the response processing module includes a sixth diode D6, and the second resistor R2 can be directly electrically connected to the second current-carrying line 120, for example, referring to... Figure 1 As shown, it can also be electrically connected to the second current-carrying line 120 through the sixth diode D6 in the response processing module, for example, referring to... Figure 5 As shown.

[0058] Similarly, the switching pin of the first switching transistor Q1 can be directly connected to the second current-carrying line 120, for example, referring to... Figure 1 As shown, it can also be electrically connected to the second current-carrying line 120 through the sixth diode D6 in the trigger module 420, for example, referring to... Figure 5 As shown.

[0059] Reference Figure 3 and Figure 4In some embodiments of the present invention, the circuit board is provided with a first pad L-1 for soldering the first current-carrying line 110 in the upper region; one end of the first resistor R1 is adjacent to and electrically connected to the first pad L-1. The upper region is also provided with a third through hole R1-2 that is adjacent to and electrically connected to the other end of the first resistor R1, a fourth through hole D2-1 that is adjacent to and electrically connected to the anode of the second diode D2, a fifth through hole D2-2 that is adjacent to and electrically connected to the cathode of the second diode D2, and a sixth through hole D1-1 that is adjacent to and electrically connected to the anode of the first diode D1; the back side of the upper region is provided with a second trace Z02 that connects the third through hole R1-2 and the fourth through hole D2-1, and a third trace Z03 that connects the fifth through hole D2-2 and the sixth through hole D1-1; The second resistor R2 is adjacent to and electrically connected to the first diode D1; the connection point between the first diode D1 and the second resistor R2 is adjacent to and electrically connected to the response processing module. The fifth through hole D2-2 is also adjacent to and electrically connected to the control pin of the first switching transistor Q1.

[0060] In this embodiment, through the above-mentioned vias and traces, a conduction path is achieved in the upper region of the circuit board: first current-carrying line 110 - first pad L-1 - first resistor R1 - third via R1-2 - second trace Z02 - fourth via D2-1 - second diode D2 - fifth via D2-2 - third trace Z03 - sixth via D1-1 - first diode D1 - second resistor R2. This allows the first resistor R1, second diode D2, and first diode D1 to be flexibly distributed in different positions in the upper region of the circuit board, greatly increasing the flexibility of the layout of other modules and reducing layout restrictions.

[0061] Reference Figure 1 The voltage divider trigger module 520 includes a third resistor R3 and a fourth resistor R4. The output terminal of the power module 200, the third resistor R3, the fourth resistor R4, and the second current-carrying line 120 are electrically connected in sequence. The connection point of the third resistor R3 and the fourth resistor R4 is connected to the control pin of the first switching transistor Q1. The voltage divider trigger module 520 divides the voltage difference between the output terminal of the power module 200 and the second current-carrying line 120 by using the third resistor R3 and the fourth resistor R4 in series. This allows it to provide a first-level voltage signal to the control pin of the first switching transistor Q1 when the DC detection voltage +18V output by the power module 200 is valid, thus turning on the first switching transistor Q1. Conversely, it provides a 0V low-level voltage signal to the control pin of the first switching transistor Q1 when the DC detection voltage +18V output by the power module 200 is invalid, thus turning off the first switching transistor Q1. Similarly, it should be noted that the fourth resistor R4 can be directly electrically connected to the second current-carrying line 120, for example, referring to... Figure 1As shown, it can also be electrically connected to the second current-carrying line 120 through the sixth diode D6 in the trigger module 420, for example, referring to... Figure 5 As shown.

[0062] Reference Figure 3 and Figure 4 In some embodiments of the circuit board provided by this utility model, the third resistor R3 and the fourth resistor R4 are arranged adjacent to each other. One end of the third resistor R3 is adjacent to and electrically connected to the second through hole +18V-1. The fourth resistor R4 is adjacent to the first switching transistor Q1. The upper region is also provided with a second pad N-1 for soldering the second current-carrying line 120. One end of the fourth resistor R4, one switch pin of the first switching transistor Q1, and the second pad N-1 are electrically connected through the fourth trace Z04 on the front side of the upper region. The other end of the third resistor R3, the other end of the fourth resistor R4, and the other switch pin of the first switching transistor Q1 are electrically connected.

[0063] In this embodiment, through the above layout and wiring arrangement, a small space can be used in the upper area of ​​the circuit board to realize the conduction path of DC detection voltage +18V - second via +18V-1 - third resistor R3 - fourth resistor R4 - fourth trace Z04 - second pad N-1 - second current-carrying line 120, and the connection point of the third resistor R3 and the fourth resistor R4 can directly realize the transmission of the voltage divider signal to the first switching transistor Q1.

[0064] Reference Figure 1 or Figure 5The voltage divider injection module 510 also includes a first capacitor C1 and a second capacitor C2. The first capacitor C1 is connected in parallel with the second resistor R2, and the two ends of the second capacitor C2 are respectively connected to the two switching pins of the first switching transistor Q1. By setting the first capacitor C1 connected in parallel with the second resistor R2 and the second capacitor C2 connected in parallel with the two switching pins of the first switching transistor Q1 in the voltage divider injection module 510, a power-on soft start function is realized. This allows the first capacitor C1 and the second capacitor C2 to be charged at the moment the detection and protection device is powered on, before the power supply module 200 has established the DC detection voltage of +18V. The charging voltage will not exceed the tripping voltage of the response processing module, and no false tripping phenomenon will occur upon power-on. It should be noted that it may take some time for the power module 200 to establish a DC detection voltage of +18V. If the power module 200 has not yet established a DC detection voltage of +18V at the moment the detection and protection device is powered on, the voltage divider trigger module 520 provides a low-level voltage signal of 0V to the control pin of the first switching transistor Q1, causing the first switching transistor Q1 to turn off. At this time, if there is no first capacitor C1 and second capacitor C2, a conducting loop will be directly formed between the first current-carrying line 110, the first resistor R1, the first diode D1, the second resistor R2, and the second current-carrying line 120, causing the response processing module to disconnect the power connection between the input and output terminals of the power line, resulting in a false tripping phenomenon upon power-on.

[0065] Reference Figure 3 In some embodiments of the present invention, the circuit board provided has a first capacitor C1 adjacent to and connected in parallel with a second resistor R2; a second capacitor C2 located between a first switch Q1 and a second diode D2; one end of the second capacitor C2 is adjacent to and electrically connected to the cathode of the second diode D2, and the other end is located in the fourth trace Z04.

[0066] In this embodiment, by appropriately arranging the positions of the first capacitor C1 and the second capacitor C2, the layout space of the voltage divider injection module 510 on the circuit board can be reduced.

[0067] Reference Figure 1The first shielding conductor 130 includes a first end a near the input end of the power line and a second end b near the output end of the power line; the second shielding conductor 140 includes a third end d near the input end of the power line and a fourth end e near the output end of the power line; the self-test path module 300 includes a first self-test unit 310 and a second self-test unit 320, and the detection protection device further includes a third connection unit 330; the first self-test unit 310 is electrically connected between the output end of the power module 200 and the second current-carrying line 120, and is provided with a first detection end X; the second self-test unit 320 is electrically connected to the first self-test unit 310, the first end a and the third end d, and is provided with a second detection end Y; the third connection unit 330 is electrically connected to the second end b, the fourth end e and the second current-carrying line 120; the response processing module is electrically connected to the first detection end X, the second detection end Y, the first current-carrying line 110 and the second current-carrying line 120 respectively. The first self-test unit 310, the second self-test unit 320, and the third connection unit 330 in the self-test path module 300, together with the first shielding conductor 130 and the second shielding conductor 140, form an open-circuit self-test path. A first detection terminal X and a second detection terminal Y are provided. When there is no leakage or open circuit, the potentials of the first detection terminal X and the second detection terminal Y remain constant, and the response processing module will not be triggered. When leakage or open circuit occurs, the potentials of the first detection terminal X and the second detection terminal Y change, triggering the response processing module to disconnect the power connection between the input and output terminals of the power cord, ensuring the power supply safety of the power cord. This power cord detection and protection device can effectively and reliably detect leakage in the power cord and detect open circuits in the shielding conductors of the power cord.

[0068] Continue to refer to Figure 1 The response processing module includes a fault signal processing module 410 and a trigger module 420. The fault signal processing module 410 is electrically connected to the first detection terminal X, the second detection terminal Y, and the trigger module 420, respectively. It is used to acquire the open circuit signal generated when the first shielding conductor 130 and / or the second shielding conductor 140 is open, and to acquire the leakage current signal detected by the first shielding conductor 130 and / or the second shielding conductor 140. In response to the open circuit signal or the leakage current signal, it outputs a first trip trigger signal. The trigger module 420 is electrically connected to the fault signal processing module 410, the first current-carrying line 110, and the second current-carrying line 120, respectively. The trigger module 420 is configured to disconnect the power connection between the input and output terminals of the power line through the switch module 1000 in response to receiving the first trip trigger signal.

[0069] Reference Figure 3 and Figure 4In some embodiments of the present invention, the circuit board provided has a first self-test unit 310 located to the left of the second through hole +18V-1 and electrically connected to the second through hole +18V-1; a second self-test unit 320 located above the first self-test unit 310 and electrically connected to the first self-test unit 310; and a fault signal processing module 410 located to the right of the first self-test unit 310 and below the second self-test unit 320.

[0070] In this embodiment, the first self-test unit 310 is arranged adjacent to the second through hole +18V-1, so that the DC detection voltage +18V can be directly obtained from the second through hole +18V-1; the first self-test unit 310, the second self-test unit 320 and the fault signal processing module 410 are arranged adjacent to each other, so that the signal transmission between the three can be conveniently realized.

[0071] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the circuit board is provided with a seventh through hole R8-1 that is adjacent to and electrically connected to the second self-test unit 320 in the upper region. The lower region is also provided with an eighth through hole ad for welding the first end a and the third end d; The back of the circuit board also has a fifth trace Z05 that connects the seventh through hole R8-1 and the eighth through hole ad.

[0072] In this embodiment, by setting the above through holes and traces, the conduction path of the first end a / third end d-eighth through hole ad-fifth trace Z05-seventh through hole R8-1-second self-test unit 320 is realized, so that the first shielding conductor 130 and the second shielding conductor 140 cooperate with the first self-test unit 310 and the second self-test unit 320 to construct the detection path.

[0073] Reference Figure 1The trigger module 420 includes a thyristor Q4, a sixth diode D6, and a trip coil Lx for generating electromagnetic force to drive the switch module 1000 to disconnect the power connection. The first current-carrying line 110, the trip coil Lx, the thyristor Q4, the sixth diode D6, and the second current-carrying line 120 are electrically connected in sequence. The control pin of the thyristor Q4 is electrically connected to the power failure detection module 500, the collector of the second transistor Q2, and the collector of the third transistor Q3. When the first trip trigger signal is output from the collector of the second transistor Q2 or the collector of the third transistor Q3 to the control pin of the thyristor Q4, and the positive half-cycle of the AC power supply is reached, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q4 is turned on, forming a strong current path of the first current-carrying line 110-trip coil Lx-thyristor Q4-sixth diode D6-second current-carrying line 120; the trip coil Lx generates a strong electromagnetic force, thereby driving the switch module 1000 to disconnect the power connection between the input and output terminals of the power supply line.

[0074] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the circuit board is provided in the upper region with a ninth through hole Lx-1 and a tenth through hole Lx-2 for soldering the trip coil Lx. The ninth through hole Lx-1 is adjacent to and electrically connected to the first solder pad L-1. The thyristor Q4 is adjacent to the voltage divider injection module 510 and is electrically connected to the connection point of the first diode D1 and the second resistor R2. The upper region is also provided with an eleventh through hole Q4-1 that is adjacent to and electrically connected to the thyristor Q4, and the back of the upper region is also provided with a sixth trace Z06 that connects the tenth through hole Lx-2 and the eleventh through hole Q4-1. The cathode of the sixth diode D6 is adjacent to and electrically connected to the second pad N-1.

[0075] In this embodiment, the above-mentioned through-holes and traces are used to achieve the following conduction path: first current-carrying line 110 - first pad L-1 - ninth through-hole Lx-1 - trip coil Lx - tenth through-hole Lx-2 - sixth trace Z06 - eleventh through-hole Q4-1 - thyristor Q4 - sixth diode D6 - second pad N-1 - second current-carrying line 120.

[0076] Reference Figure 1The fault signal processing module 410 includes a second transistor Q2 and a third transistor Q3; the base of the second transistor Q2 and the emitter of the third transistor Q3 are both connected to the first detection terminal X; the emitter of the second transistor Q2 and the base of the third transistor Q3 are both connected to the second detection terminal Y; the collector of the second transistor Q2 and the collector of the third transistor Q3 are connected together and connected to the trigger module 420 to output a first trip trigger signal to the trigger module 420. When the voltage received at the emitter of the second transistor Q2 is greater than the voltage received at the base of the second transistor Q2, the emitter junction of the second transistor Q2 is forward biased and thus conducts, thereby outputting a first trip trigger signal to the trigger module 420 through the collector of the second transistor Q2; similarly, when the voltage received at the emitter of the third transistor Q3 is greater than the voltage received at the base of the third transistor Q3, the emitter junction of the third transistor Q3 is forward biased and thus conducts, thereby outputting a first trip trigger signal to the trigger module 420 through the collector of the third transistor Q3.

[0077] Reference Figure 3 In some embodiments of the present invention, the second transistor Q2 and the third transistor Q3 are arranged adjacent to each other, and the detection and protection device further includes a twenty-second resistor R22; one end of the twenty-second resistor R22 is adjacent to and electrically connected to the control pin of the thyristor Q4, and the other end is electrically connected to the collector of the second transistor Q2 and the collector of the third transistor Q3 through the seventh trace Z07 on the front of the upper region.

[0078] In this embodiment, the fault signal processing module 410 and the trigger module 420 are electrically connected by setting the seventh trace Z07, so that the first trip trigger signal output by the fault signal processing module 410 is transmitted to the control pin of the thyristor Q4 in the trigger module 420 after passing through the twenty-second resistor R22.

[0079] Reference Figure 3 In some embodiments of the present invention, a twelfth through hole D6-1 is provided below the seventh trace Z07, and an eighth trace Z08 is provided on the front of the upper region, which connects the twelfth through hole D6-1 with the anode of the sixth diode D6. Above the seventh trace Z07 is the thirteenth through hole D6-2, and on the front of the upper area is the ninth trace Z09, which connects the thirteenth through hole D6-2, the second resistor R2 and the thyristor Q4. The back of the upper area is also provided with the tenth trace Z10, which connects the twelfth through hole D6-1 and the thirteenth through hole D6-2.

[0080] In this embodiment, the above-mentioned vias and traces are used to achieve the conduction path of the anode of the thyristor Q4 - the ninth trace Z09 - the thirteenth via D6-2 - the tenth trace Z10 - the twelfth via D6-1 - the eighth trace Z08 - the sixth diode D6. This allows for the electrical connection between the thyristor Q4 and the sixth diode D6 across the seventh trace Z07, and also enables the electrical connection between the voltage divider injection module 510 and the sixth diode D6.

[0081] Reference Figure 1 The first self-test unit 310 includes a third diode D3, a fifth resistor R5, and a sixth resistor R6. The output terminal of the power module 200, the third diode D3, the fifth resistor R5, the sixth resistor R6, and the second current-carrying line 120 are sequentially and electrically connected. The connection point of the fifth resistor R5 and the sixth resistor R6 serves as the first detection terminal X. The voltage between the output terminal of the power module 200 and the second current-carrying line 120 is divided by the third diode D3, the fifth resistor R5, and the sixth resistor R6 in the first self-test unit 310 to determine the potential of the first detection terminal X.

[0082] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the fifth resistor R5, the sixth resistor R6, and the third diode D3 are arranged sequentially from top to bottom in the upper region of the circuit board. The anode of the third diode D3 is adjacent to and electrically connected to the second through hole +18V-1; The upper region is also provided with a fourteenth through hole D3-2 that is adjacent to and electrically connected to the cathode of the third diode D3, and a fifteenth through hole D3-3 that is adjacent to and electrically connected to the upper end of the fifth resistor R5. The back side of the upper region is also provided with an eleventh trace Z11 that connects the fourteenth through hole D3-2 and the fifteenth through hole D3-3. The lower end of the fifth resistor R5, the upper end of the sixth resistor R6, the base of the second transistor Q2, and the emitter of the third transistor Q3 are electrically connected through the twelfth trace Z12 located on the front of the upper region. The lower end of the sixth resistor R6 is located in the eighth trace Z08.

[0083] In this embodiment, the above vias and traces are configured to achieve the following conduction path: DC detection voltage +18V - second via +18V-1 - third diode D3 - fourteenth via D3-2 - eleventh trace Z11 - fifteenth via D3-3 - fifth resistor R5 - sixth resistor R6 - eighth trace Z08 - sixth diode D6 - second pad N-1 - second current-carrying line 120. Simultaneously, the voltage divider signal at the connection point of the fifth resistor R5 and the sixth resistor R6 is transmitted to the second transistor Q2 and the third transistor Q3 in the fault signal processing module 410 via the twelfth trace Z12.

[0084] Reference Figure 1 The second self-test unit 320 includes a seventh resistor R7 and an eighth resistor R8. The connection point of the third diode D3 and the fifth resistor R5 is connected to one end of the seventh resistor R7. The other end of the seventh resistor R7 is connected to the first terminal a, the third terminal d and one end of the eighth resistor R8. The other end of the eighth resistor R8 serves as the second detection terminal Y.

[0085] Specifically, refer to Figure 3 In some embodiments of the circuit board provided by this utility model, one end of the seventh resistor R7 is adjacent to and electrically connected to the upper end of the fifth resistor R5; the other end of the seventh resistor R7, one end of the eighth resistor R8, and the seventh through hole R8-1 are electrically connected through the thirteenth trace Z13 on the front side of the upper region; the other end of the eighth resistor R8 is adjacent to and electrically connected to the emitter of the second transistor Q2 and the base of the third transistor Q3. This facilitates convenient electrical connections between the various components.

[0086] It is understood that in some embodiments, the second self-test unit 320 may also include a fourth capacitor C4; the fourth capacitor C4 is located between the seventh resistor R7 and the eighth resistor R8, one end of the fourth capacitor C4 is adjacent to and electrically connected to the third transistor Q3, and the other end is adjacent to and electrically connected to the eighth resistor R8.

[0087] Reference Figure 1 The third connection unit 330 includes a ninth resistor R9, a tenth resistor R10, a fourth diode D4, and a fifth diode D5; the second terminal b, the ninth resistor R9, the fourth diode D4, and the second current-carrying line 120 are electrically connected in sequence; the fourth terminal e, the tenth resistor R10, the fifth diode D5, and the second current-carrying line 120 are electrically connected in sequence. Through the seventh resistor R7 and the eighth resistor R8 in the second self-test unit 320, the ninth resistor R9 and the tenth resistor R10 in the third connection unit 330, the fourth diode D4 and the fifth diode D5, in conjunction with the first shielding conductor 130 and the second shielding conductor 140, a special detection path is formed. This path enables the detection of both the first and second shielding conductors 130 and 140, and determines the potential of the second detection terminal Y. This allows the potential of either the first detection terminal X or the second detection terminal Y to be affected when leakage signals are detected in the first or second shielding conductor 130, the second shielding conductor 140, or both are open-circuited. This triggers the response processing module to disconnect the power connection between the input and output terminals of the power cord, ensuring the power supply safety of the power cord. It should be noted that the third connection unit 330 is located at the end of the power cord near the output terminal.

[0088] Reference Figure 5 and 6In some embodiments of the present invention, the circuit board provided includes a voltage divider trigger module 520, which includes a third resistor R3 and a fourth resistor R4 arranged adjacent to each other. One end of the third resistor R3 is adjacent to and electrically connected to the second through hole +18V-1; The fourth resistor R4 is adjacent to the first switch Q1; one end of the fourth resistor R4 and one switch pin of the first switch Q1 are electrically connected to the anode of the sixth diode D6 through the eighth trace Z08. The other end of the third resistor R3, the other end of the fourth resistor R4, and the other switch pin of the first switch Q1 are electrically connected.

[0089] In this embodiment, through the above layout and routing, a relatively small space can be used in the upper region of the circuit board to realize the conduction path of DC detection voltage +18V - second via +18V-1 - third resistor R3 - fourth resistor R4 - eighth trace Z08 - sixth diode D6 - second pad N-1 - second current-carrying line 120. Furthermore, the connection point of the third resistor R3 and the fourth resistor R4 can directly transmit the voltage divider signal to the first switching transistor Q1.

[0090] Understandable, Figure 6 The circuit board layout embodiment shown is similar to... Figure 3 The main difference between the circuit board layout examples shown and those described is that... Figure 6 The embodiment shown does not have a fourth trace Z04 directly electrically connected to the second pad N-1. Instead, one end of the fourth resistor R4 and one switch pin of the first switch Q1 are electrically connected to the anode of the sixth diode D6 through the eighth trace Z08, and then the cathode of the sixth diode D6 is electrically connected to the second pad N-1.

[0091] Reference Figure 1 The detection and protection device also includes a test module 600 connected in parallel with the seventh resistor R7. The test module 600 includes a twenty-first resistor R21 connected in series and a test switch TEST. When the test switch TEST in the test module 600 is pressed, it is equivalent to connecting the twenty-first resistor R21 in parallel across the seven resistor R7, thereby changing the potential of the second detection terminal Y, thus triggering the response processing module to operate, and thus testing whether the leakage current detection function of the detection and protection device is intact.

[0092] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the circuit board is provided with a first contact area TEST-1 and a second contact area TEST-2 in the upper region for the two ends of the test switch TEST to be pressed. One end of the twenty-first resistor R21 is electrically connected to the cathode of the third diode D3 through the fourteenth trace Z14 located on the front of the upper region, and the other end is adjacent to and electrically connected to the first contact area TEST-1. The upper area is also provided with a sixteenth through hole TEST-2-1 that is adjacent to and electrically connected to the second touch area TEST-2. The back of the upper area is provided with a fifteenth trace Z15 that is electrically connected to the sixteenth through hole TEST-2-1 and the fifth trace Z05.

[0093] In this embodiment, the above settings achieve the following conduction path: third diode D3 - fourteenth trace Z14 - twenty-first resistor R21 - first contact area TEST-1 - test switch TEST - second contact area TEST-2 - sixteenth via TEST-2-1 - fifteenth trace Z15 - fifth trace Z05 - seventh via R8-1 - thirteenth trace Z13 - seventh resistor R7.

[0094] Reference Figure 1 The trigger module 420 also includes a first varistor ZR1 connected in parallel with the silicon controlled rectifier Q4. It is understood that a varistor is a resistor with non-linear current-voltage characteristics, mainly used for voltage clamping when a circuit is subjected to overvoltage, absorbing excess current to protect sensitive devices. Therefore, setting the first varistor ZR1 in parallel with the silicon controlled rectifier Q4 can protect the silicon controlled rectifier Q4 from damage.

[0095] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the circuit board is provided in the upper region with an eighteenth through hole ZR1-1 and a nineteenth through hole ZR1-2 for soldering the first varistor ZR1. The eighteenth through hole ZR1-1 is located on the sixth trace Z06; The nineteenth through-hole ZR1-2 is electrically connected to the eighth trace Z08 via the eighteenth trace Z18 located in the upper region.

[0096] In this embodiment, the above settings achieve the following conduction path: trip coil Lx - tenth through hole Lx-2 - sixth trace Z06 - eighteenth through hole ZR1-1 - first varistor ZR1 - nineteenth through hole ZR1-2 - eighteenth trace Z18 - eighth trace Z08 - sixth diode D6 - second pad N-1 - second current-carrying line 120.

[0097] Reference Figure 1The detection and protection device also includes an indicator module 700, which includes an eleventh resistor R11 and a light-emitting diode (LED) LED1. The output terminal of the power supply module 200, the eleventh resistor R11, the LED1, and the second current-carrying line 120 are electrically connected in sequence. When the +18V DC detection voltage output by the power supply module 200 is valid, a conducting circuit is formed between the output terminal of the power supply module 200, the eleventh resistor R11, the LED1, and the second current-carrying line 120, and the LED1 is lit. Conversely, when the +18V DC detection voltage output by the power supply module 200 fails, the LED1 is turned off, thus alerting the user.

[0098] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the indicator module 700 is located above the ninth trace Z09 on the circuit board. The upper region is also provided with a seventeenth through hole R11-1 that is adjacent to and electrically connected to one end of the eleventh resistor R11; the back side of the upper region is also provided with a sixteenth trace Z16 that is electrically connected to the seventeenth through hole R11-1 and the second through hole +18V-1. The other end of the eleventh resistor R11 is adjacent to and electrically connected to the anode of the light-emitting diode LED1; The upper area also has a cathode of the light-emitting diode LED1 connected to the seventeenth trace Z17 of the ninth trace Z09 on the front side.

[0099] In this embodiment, the above settings achieve the following conduction path: second via +18V-1 - sixteenth trace Z16 - seventeenth via R11-1 - eleventh resistor R11 - LED1 - seventeenth trace Z17 - ninth trace Z09 - thirteenth via D6-2 - tenth trace Z10 - twelfth via D6-1 - eighth trace Z08 - sixth diode D6 - second pad N-1 - second current-carrying line 120.

[0100] Reference Figure 3 and Figure 4 In some embodiments of the present invention, the circuit board is provided with a fuse FUSE located in the upper region, and one end of the fuse FUSE is adjacent to and electrically connected to the first pad L-1. The upper area is also provided with a twentieth through hole FUSE-1 that is adjacent to and electrically connected to the other end of the fuse FUSE; The lower area is also provided with a 21st through hole ZR2-1 and a 22nd through hole ZR2-2 for welding the second varistor ZR2; The back of the circuit board also has a nineteenth trace Z19 that connects the twentieth through hole FUSE-1 and the twenty-first through hole ZR2-1; The front side of the circuit board also has a twentieth trace Z20 that connects the twenty-second through hole ZR2-2 to the second pad N-1.

[0101] In this embodiment, the above settings achieve the following conduction path: first current-carrying line 110 - first pad L-1 - fuse FUSE - twentieth through hole FUSE-1 - nineteenth trace Z19 - twenty-first through hole ZR2-1 - second varistor ZR2 - twenty-second through hole ZR2-2 - twentieth trace Z20 - second pad N-1 - second current-carrying line 120.

[0102] Below, with Figure 1 The illustrated embodiments describe the detection and protection device provided by this utility model under various conditions: 1. When the detection and protection device is in normal condition, the current signal flows as follows: Firstly, a conduction loop is formed from the output terminal of the power module 200 through the third diode D3, the seventh resistor R7, the first shielding conductor 130, the ninth resistor R9 and the fourth diode D4, to the second current-carrying line 120. Secondly, a conduction loop is formed from the output terminal of the power module 200 through the third diode D3, the seventh resistor R7, the second shielding conductor 140, the tenth resistor R10 and the fifth diode D5, to the second current-carrying line 120. Thirdly, a conduction loop is formed from the output terminal of the power module 200 through the third diode D3, the fifth resistor R5, the sixth resistor R6 and the sixth diode D6, to the second current-carrying line 120. Fourthly, a conduction loop is formed from the output terminal of the power module 200 through the eleventh resistor R11, the light-emitting diode LED1 and the sixth diode D6, to the second current-carrying line 120. Fifthly, a conduction loop is formed from the output terminal of the power module 200 through the third resistor R3 and the fourth resistor R4 to the second current-carrying line 120; and the first switching transistor Q1 is turned on. Sixthly, a conduction loop is formed from the first current-carrying line 110 through the first resistor R1, the second diode D2 and the first switch Q1, to the second current-carrying line 120.

[0103] 2. When the first current-carrying line 110 leaks current to the first shielding conductor 130, a leakage current signal is sent to the second transistor Q2 through the second detection terminal Y, causing the second transistor Q2 to conduct and output a trip trigger signal to the trigger module 420.

[0104] Specifically, after the first shielding conductor 130 obtains the leakage signal, the leakage current provided by the first shielding conductor 130 flows from the first end a of the first shielding conductor 130 through the seventh resistor R7, the fifth resistor R5 and the sixth resistor R6 in sequence, and from the first end a of the first shielding conductor 130 through the eighth resistor R8 and then from the second detection end Y to the emitter of the second transistor Q2, so that the emitter of the second transistor Q2 receives a voltage greater than the base voltage, so that the second transistor Q2 is turned on; After the second transistor Q2 is turned on, current flows through the second transistor Q2, and from the collector of the second transistor Q2 through the twenty-second resistor R22 to the second resistor R2, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q4 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q4 is turned on, forming a strong current path of the first current-carrying line 110 - trip coil Lx - thyristor Q4 - sixth diode D6 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 1000 to disconnect the power connection between the input and output terminals of the power supply line.

[0105] 3. When the second current-carrying line 120 leaks current to the second shielding conductor 140, a leakage current signal is sent to the third transistor Q3 through the first detection terminal X, causing the third transistor Q3 to conduct and output a trip trigger signal to the trigger module 420.

[0106] Specifically, the current supplied by the output terminal of the power module 200 flows through the third diode D3 and the seventh resistor R7 to the second shielding conductor 140, and then flows directly to the second current-carrying line 120, no longer flowing through the tenth resistor R10 and the fifth diode D5. This causes the potential of the second detection terminal Y to decrease, and the potential of the first detection terminal X to be greater than the potential of the second detection terminal Y. This forms a conducting loop from the output terminal of the power module 200 through the third diode D3, the fifth resistor R5, the first detection terminal X, the third transistor Q3, the second detection terminal Y, and the eighth resistor R8 to the second shielding conductor 140. The voltage received by the emitter of the third transistor Q3 is greater than the voltage of its base, causing the third transistor Q3 to conduct. After the third transistor Q3 is turned on, current flows through the third transistor Q3, and from the collector of the third transistor Q3 through the twenty-second resistor R22 to the second resistor R2, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q4 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q4 is turned on, forming a strong current path of the first current-carrying line 110 - trip coil Lx - thyristor Q4 - sixth diode D6 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 1000 to disconnect the power connection between the input and output terminals of the power supply line.

[0107] 4. When the first shielding conductor 130 is open-circuited, an open-circuit signal is sent to the second transistor Q2 through the second detection terminal Y, causing the second transistor Q2 to conduct and output a trip trigger signal to the trigger module 420.

[0108] Specifically, after the first shielding conductor 130 is open-circuited, the current supplied by the output terminal of the power module 200 cannot flow through the first shielding conductor 130 after passing through the third diode D3 and the seventh resistor R7, causing the potential of the second detection terminal Y to rise. After passing through the eighth resistor R8, the current flows from the second detection terminal Y to the emitter of the second transistor Q2. The voltage received at the emitter of the second transistor Q2 is greater than the voltage at the base, causing the second transistor Q2 to conduct. After the second transistor Q2 is turned on, the current flows from the second detection terminal Y through the second transistor Q2, and from the collector of the second transistor Q2 through the twenty-second resistor R22 to the second resistor R2, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q4 increases. When the positive half-cycle of the AC power supply is reached, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q4 is turned on, forming a strong current path of the first current-carrying line 110 - trip coil Lx - thyristor Q4 - sixth diode D6 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 1000 to disconnect the power connection between the input and output terminals of the power supply line.

[0109] 5. When the second shielding conductor 140 is open-circuited, an open-circuit signal is sent to the second transistor Q2 through the second detection terminal Y, causing the second transistor Q2 to conduct and output a trip trigger signal to the trigger module 420.

[0110] Specifically, after the second shielding conductor 140 is open-circuited, the current supplied by the output terminal of the power module 200 cannot flow through the second shielding conductor 140 after passing through the third diode D3 and the seventh resistor R7, causing the potential of the second detection terminal Y to rise. After passing through the eighth resistor R8, the current flows from the second detection terminal Y to the emitter of the second transistor Q2. The voltage received at the emitter of the second transistor Q2 is greater than the voltage at the base, causing the second transistor Q2 to conduct. After the second transistor Q2 is turned on, the current flows from the second detection terminal Y through the second transistor Q2, and from the collector of the second transistor Q2 through the twenty-second resistor R22 to the second resistor R2, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q4 increases. When the positive half-cycle of the AC power supply is reached, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q4 is turned on, forming a strong current path of the first current-carrying line 110 - trip coil Lx - thyristor Q4 - sixth diode D6 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 1000 to disconnect the power connection between the input and output terminals of the power supply line.

[0111] 6. When the test switch TEST is pressed: a current signal is sent to the second transistor Q2 through the second detection terminal Y, so that the second transistor Q2 is turned on, and a trip trigger signal is output to the trigger module 420.

[0112] Specifically, after the test switch TEST is pressed, the two ends of the seventh resistor R7 are connected in parallel to the twenty-first resistor R21, which raises the potential of the second detection terminal Y. After passing through the eighth resistor R8, the current flows from the second detection terminal Y to the emitter of the second transistor Q2. The emitter of the second transistor Q2 receives a voltage greater than the base voltage, which turns the second transistor Q2 on. After the second transistor Q2 is turned on, the current flows from the second detection terminal Y through the second transistor Q2, and from the collector of the second transistor Q2 through the twenty-second resistor R22 to the second resistor R2, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q4 increases. When the positive half-cycle of the AC power supply is reached, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q4 is turned on, forming a strong current path of the first current-carrying line 110 - trip coil Lx - thyristor Q4 - sixth diode D6 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 1000 to disconnect the power connection between the input and output terminals of the power supply line.

[0113] Additionally, refer to Figure 7 The second aspect of this utility model provides an electrical connection device, including a circuit board as described in the first aspect embodiment, a power cord 100, and a detection and protection device disposed on the circuit board and connected to the power cord 100.

[0114] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A circuit board for an electrical connection device, characterized in that, The electrical connection device includes a power cord and a detection and protection device electrically connected to the power cord; The power line includes a first current-carrying line, a second current-carrying line, and a shielding conductor disposed outside the first current-carrying line and the second current-carrying line; The detection and protection device includes a power module, a self-test path module, and a response processing module. The circuit board includes a lower region and an upper region; The power module is located in the lower region and is used to output a DC detection voltage. The self-test path module and the response processing module are located in the upper region; the self-test path module is electrically connected to the shielding conductor and the output terminal of the power module respectively; the response processing module is electrically connected to the first current-carrying line, the second current-carrying line and the self-test path module respectively, and is used to disconnect the power connection between the input terminal and the output terminal of the power line when the shielding conductor is open-circuited or when the shielding conductor detects a leakage signal.

2. The circuit board according to claim 1, characterized in that, It also includes a power failure detection module disposed in the upper region. The power failure detection module is used to trigger the response processing module to disconnect the power connection between the input and output terminals of the power line when the DC detection voltage output by the power module fails.

3. The circuit board according to claim 2, characterized in that, The power failure detection module includes a first switching transistor, a voltage divider injection module located to the right of the first switching transistor and electrically connected to the first switching transistor, and a voltage divider trigger module located to the left of the first switching transistor and electrically connected to the first switching transistor. The voltage divider injection module is used to provide a second trip trigger signal to the response processing module when the DC detection voltage output by the power module fails. The voltage divider trigger module is used to control the first switch to turn on when the DC detection voltage output by the power module is valid, so that the voltage divider injection module cannot provide the second trip trigger signal to the response processing module.

4. The circuit board according to claim 3, characterized in that, The power module includes a second electrolytic capacitor. The lower region is provided with a first through hole for welding the anode of the second electrolytic capacitor. The upper region is provided with a second through hole that is adjacent to and electrically connected to the voltage divider trigger module. The back of the circuit board is provided with a first trace connecting the first through hole and the second through hole.

5. The circuit board according to claim 4, characterized in that, The voltage divider injection module includes a first resistor, a second diode, and a second resistor that are electrically connected in sequence. The upper region is provided with a first pad for soldering the first current-carrying line; one end of the first resistor is adjacent to and electrically connected to the first pad. The upper region is further provided with a third through hole adjacent to and electrically connected to the other end of the first resistor, a fourth through hole adjacent to and electrically connected to the anode of the second diode, a fifth through hole adjacent to and electrically connected to the cathode of the second diode, and a sixth through hole adjacent to and electrically connected to the anode of the first diode; the back side of the upper region is provided with a second trace connecting the third through hole and the fourth through hole, and a third trace connecting the fifth through hole and the sixth through hole; The second resistor is adjacent to and electrically connected to the first diode; the connection point between the first diode and the second resistor is adjacent to and electrically connected to the response processing module. The fifth through hole is also adjacent to and electrically connected to the control pin of the first switching transistor.

6. The circuit board according to claim 5, characterized in that, The voltage divider trigger module includes a third resistor and a fourth resistor arranged adjacent to each other; One end of the third resistor is adjacent to and electrically connected to the second through hole; The fourth resistor is adjacent to the first switching transistor; the upper region is also provided with a second pad for soldering the second current-carrying line; one end of the fourth resistor, one switching pin of the first switching transistor, and the second pad are electrically connected through a fourth trace provided on the front side of the upper region; The other end of the third resistor, the other end of the fourth resistor, and the other switch pin of the first switch are electrically connected.

7. The circuit board according to claim 6, characterized in that, The voltage divider injection module also includes a first capacitor and a second capacitor; The first capacitor is adjacent to and connected in parallel with the second resistor; The second capacitor is located between the first switch and the second diode; one end of the second capacitor is adjacent to and electrically connected to the cathode of the second diode, and the other end is located in the fourth trace.

8. The circuit board according to claim 6, characterized in that, The self-test path module includes a first self-test unit and a second self-test unit; The first self-test unit is located to the left of the second through hole and is electrically connected to the second through hole; The second self-test unit is located above the first self-test unit and is electrically connected to the first self-test unit; The response processing module includes a fault signal processing module, which is located to the right of the first self-test unit and below the second self-test unit. The fault signal processing module is used to acquire the open circuit signal generated when the shielding conductor is open and the leakage current signal detected by the shielding conductor, and output a first tripping trigger signal in response to the open circuit signal or the leakage current signal.

9. The circuit board according to claim 8, characterized in that, The shielding conductor includes a first shielding conductor covering the first current-carrying line and a second shielding conductor covering the second current-carrying line; the first shielding conductor includes a first end near the input end of the power line and a second end near the output end of the power line; the second shielding conductor includes a third end near the input end of the power line and a fourth end near the output end of the power line. The upper region is also provided with a seventh through hole that is adjacent to and electrically connected to the second self-test unit; The lower region is also provided with an eighth through hole for welding the first end and the third end; The back of the circuit board is also provided with a fifth trace connecting the seventh through hole and the eighth through hole.

10. The circuit board according to claim 9, characterized in that, The response processing module further includes a trigger module, which is configured to disconnect the power connection between the input and output terminals of the power line via a switch module in response to receiving the first trip trigger signal. The triggering module includes a trip coil, a silicon controlled rectifier, and a sixth diode connected in sequence. The trip coil is used to generate electromagnetic force to drive the switching module to disconnect the power connection. The upper region is also provided with a ninth through hole and a tenth through hole for welding the trip coil. The ninth through hole is adjacent to and electrically connected to the first pad. The thyristor is adjacent to the voltage divider injection module and is electrically connected to the connection point of the first diode and the second resistor. The upper region is also provided with an eleventh through hole that is adjacent to and electrically connected to the thyristor, and the back side of the upper region is also provided with a sixth trace that connects the tenth through hole and the eleventh through hole; The cathode of the sixth diode is adjacent to and electrically connected to the second pad.

11. The circuit board according to claim 10, characterized in that, The fault signal processing module includes a second transistor and a third transistor arranged adjacent to each other; The detection and protection device further includes a 22nd resistor; one end of the 22nd resistor is adjacent to and electrically connected to the control pin of the thyristor, and the other end is electrically connected to the collector of the second transistor and the collector of the third transistor through a 7th trace on the front side of the upper region.

12. The circuit board according to claim 11, characterized in that, Below the seventh trace is a twelfth through hole, and on the front side of the upper region is an eighth trace connecting the twelfth through hole and the anode of the sixth diode; A thirteenth through hole is provided above the seventh trace, and a ninth trace connecting the thirteenth through hole, the second resistor and the thyristor is also provided on the front side of the upper region. The back of the upper region is also provided with a tenth trace connecting the twelfth through hole and the thirteenth through hole.

13. The circuit board according to claim 12, characterized in that, The first self-test unit includes a fifth resistor, a sixth resistor, and a third diode arranged sequentially from top to bottom; The anode of the third diode is adjacent to and electrically connected to the second through hole; The upper region is also provided with a fourteenth through hole adjacent to and electrically connected to the cathode of the third diode, and a fifteenth through hole adjacent to and electrically connected to the upper end of the fifth resistor. The back side of the upper region is also provided with an eleventh trace connecting the fourteenth through hole and the fifteenth through hole. The lower end of the fifth resistor, the upper end of the sixth resistor, the base of the second transistor, and the emitter of the third transistor are electrically connected through a twelfth trace disposed on the front side of the upper region. The lower end of the sixth resistor is located in the eighth trace.

14. The circuit board according to claim 13, characterized in that, The second self-test unit includes a seventh resistor and an eighth resistor; One end of the seventh resistor is adjacent to and electrically connected to the upper end of the fifth resistor; The other end of the seventh resistor, one end of the eighth resistor, and the seventh through hole are electrically connected by the thirteenth trace provided on the front of the upper region. The other end of the eighth resistor is adjacent to and electrically connected to the emitter of the second transistor and the base of the third transistor.

15. The circuit board according to claim 13, characterized in that, The detection and protection device also includes a test module, which includes a twenty-first resistor and a test switch; The upper region is provided with a first contact area and a second contact area for the two ends of the test switch to be pressed; One end of the 21st resistor is electrically connected to the cathode of the 3rd diode through the 14th trace disposed on the front side of the upper region, and the other end is adjacent to and electrically connected to the first contact area; The upper region is also provided with a sixteenth through hole that is adjacent to and electrically connected to the second contact area, and the back side of the upper region is provided with a fifteenth trace that is electrically connected to the sixteenth through hole and the fifth trace.

16. The circuit board according to claim 12, characterized in that, The voltage divider trigger module includes a third resistor and a fourth resistor arranged adjacent to each other; One end of the third resistor is adjacent to and electrically connected to the second through hole; The fourth resistor is adjacent to the first switching transistor; one end of the fourth resistor and one switching pin of the first switching transistor are electrically connected to the anode of the sixth diode through the eighth trace; The other end of the third resistor, the other end of the fourth resistor, and the other switch pin of the first switch are electrically connected.

17. The circuit board according to claim 12, characterized in that, The detection and protection device also includes an indicator module located above the ninth trace, the indicator module including an eleventh resistor and a light-emitting diode; The upper region is also provided with a seventeenth through hole that is adjacent to and electrically connected to one end of the eleventh resistor; the back side of the upper region is also provided with a sixteenth trace that is electrically connected to the seventeenth through hole and the second through hole; The other end of the eleventh resistor is adjacent to and electrically connected to the anode of the light-emitting diode; The upper region also has a seventeenth trace electrically connected to the cathode of the light-emitting diode and the ninth trace on its front side.

18. The circuit board according to claim 12, characterized in that, The triggering module also includes a first varistor; The upper region is also provided with an eighteenth and a nineteenth through hole for welding the first varistor; The eighteenth through hole is located on the sixth routing line; The nineteenth through hole is electrically connected to the eighth trace via the eighteenth trace located in the upper region.

19. The circuit board according to claim 6, characterized in that, The power module includes a second varistor; the detection and protection device also includes a fuse disposed in the upper region. One end of the fuse is adjacent to and electrically connected to the first pad; The upper region is also provided with a twentieth through hole that is adjacent to and electrically connected to the other end of the fuse. The lower region is also provided with a 21st through hole and a 22nd through hole for welding the second varistor; The back of the circuit board is also provided with a nineteenth trace connecting the twentieth through hole and the twentieth through hole; The front side of the circuit board is also provided with a twentieth trace connecting the twentieth through hole and the second pad.

20. An electrical connection device, characterized in that, Includes the circuit board, power cord, and detection and protection device disposed on the circuit board and connected to the power cord as described in any one of claims 1 to 19.

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