A power connection detection circuit

Abstract

The utility model discloses a power connection detection circuit, including sampling module and detection module, sampling module has first input, second input, third input, first output and second output, sampling module's first input connects the fire line L, sampling module's second input connects zero line N, and sampling module's third input connects the ground wire PE, detection module includes first detection unit and second detection unit, and first detection unit includes comparator U1A, first display component and second display component, comparator U1A's opposite phase input connects second output, and comparator U1A's same phase input connects reference voltage VCC, and comparator U1A's output connects first display component and second display component respectively, second detection unit includes comparator U1B and third display component, and comparator U1B's opposite phase input connects reference voltage VCC, and comparator U1B's same phase input connects first output, and third display component is connected in comparator U1B's output.

Description

Technical Field

[0001] This utility model relates to the field of reverse connection protection circuit technology, specifically to a power supply connection detection circuit. Background Technology

[0002] Existing power connection detection circuits typically determine whether the protective ground wire (PE) is energized by detecting the voltage difference between the neutral wire (N) and the protective ground wire (PE). This detection method relies on the current loop of the neutral wire (N) and cannot identify whether the live wire (L) and the neutral wire (N) are reversed. Furthermore, when the protective ground wire (PE) is floating, the false alarm rate of this power connection detection circuit is high. Utility Model Content

[0003] To address the shortcomings of existing technologies, a power supply wiring detection circuit is provided.

[0004] To achieve the above objectives, this utility model provides a power connection detection circuit, including a sampling module and a detection module. The sampling module has a first input terminal, a second input terminal, a third input terminal, a first output terminal, and a second output terminal. The first input terminal of the sampling module is connected to the live wire L, the second input terminal of the sampling module is connected to the neutral wire N, and the third input terminal of the sampling module is connected to the ground wire PE. The detection module includes a first detection unit and a second detection unit. The first detection unit includes a comparator U1A, a first display component, and a second display component. The inverting input terminal of the comparator U1A is connected to the second output terminal of the sampling module, the non-inverting input terminal of the comparator U1A is connected to the reference voltage VCC, and the output terminals of the comparator U1A are respectively connected to the first display component and the second display component. The second detection unit includes a comparator U1B and a third display component. The inverting input terminal of the comparator U1B is connected to the reference voltage VCC, the non-inverting input terminal of the comparator U1B is connected to the first output terminal of the sampling module, and the third display component is connected to the output terminal of the comparator U1B.

[0005] According to one embodiment of the present invention, the sampling module includes a first sampling unit and a second sampling unit. The first sampling unit includes a resistor R9, a resistor R14, and a Zener diode D3. One end of the resistor R9 is connected to the live wire L, and the other end of the resistor R9 is connected to the resistor R14, the Zener diode D3, and the non-inverting input terminal of the second detection unit. The other ends of the resistor R14 and the Zener diode D3 are grounded. The second sampling unit includes a resistor R10, a resistor R15, and a Zener diode D4. One end of the resistor R10 is connected to the neutral wire N, and the other end of the resistor R10 is connected to the resistor R15, the Zener diode D4, and the inverting input terminal of the first detection unit. The other ends of the resistor R15 and the Zener diode D4 are grounded.

[0006] According to one embodiment of the present invention, the first detection unit further includes a first voltage divider component, which includes a resistor R4 and a resistor R8. One end of the resistor R4 is connected to the reference voltage VCC, and the other end is connected to the non-inverting input terminal of the comparator U1A and the resistor R8, respectively. The other end of the resistor R8 is grounded.

[0007] According to one embodiment of the present invention, the first detection unit further includes a first current limiting component, which includes resistor R3 and resistor R7. One end of resistor R3 is connected to the second output terminal of the sampling module, and the other end is connected to the inverting input terminal of comparator U1A. One end of resistor R7 is connected to the reference voltage VCC, and the other end is connected to the non-inverting input terminal of comparator U1A.

[0008] According to one embodiment of the present invention, the first display component includes a resistor R2 and a light-emitting diode D2. One end of the resistor R2 is connected to a reference voltage VCC, and the other end is connected to the positive terminal of the light-emitting diode D2. The negative terminal of the light-emitting diode D2 is connected to the output terminal of the comparator U1A and the second display component.

[0009] According to one embodiment of the present invention, the second display component includes a transistor Q1, a light-emitting diode D1, and a resistor R1; the base of the transistor Q1 is connected to the output terminal of the comparator U1A and the first display component, the emitter of the transistor Q1 is grounded, the collector of the transistor Q1 is connected to the negative terminal of the light-emitting diode D1, the positive terminal of the light-emitting diode D1 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to the reference voltage VCC.

[0010] According to one embodiment of the present invention, the third display component includes a light-emitting diode D5 and a resistor R11. The negative terminal of the light-emitting diode D5 is connected to the output terminal of the comparator U1B, the positive terminal of the light-emitting diode D5 is connected to one end of the resistor R11, and the other end of the resistor R11 is connected to the reference voltage VCC.

[0011] According to one embodiment of the present invention, the second detection unit further includes a second voltage divider component, which includes a resistor R13 and a resistor R20. One end of the resistor R13 is connected to the reference voltage VCC, and the other end is connected to the resistor R20 and the inverting input terminal of the comparator U1B, respectively. The other end of the resistor R20 is grounded.

[0012] According to one embodiment of the present invention, the second detection unit further includes a second current limiting component, which includes resistor R17 and resistor R19. One end of resistor R17 is connected to the reference voltage VCC, and the other end is connected to the inverting input terminal of comparator U1B. One end of resistor R19 is connected to the first output terminal of the sampling module, and the other end is connected to the non-inverting input terminal of comparator U1B.

[0013] According to one embodiment of the present invention, the first detection unit further includes resistors R5 and R6. One end of resistor R6 is connected to the output terminal of comparator U1A, and the other end is connected to the first display component and the second display component respectively. One end of resistor R5 is connected to the reference voltage VCC, and the other end is connected to resistor R6, the first display component and the second display component respectively.

[0014] The beneficial effect of this utility model lies in the fact that by inputting the voltages of the first and second output terminals of the sampling module into comparators U1A and U1B respectively, and comparing the voltage output from the second output terminal of the sampling module with the reference voltage VCC via comparator U1A, and comparing the voltage output from the first output terminal of the sampling module with the reference voltage VCC via comparator U1B, the high or low level signal output from comparator U1A controls the first and second display components to light up or turn off, and the high or low level signal output from comparator U1B controls the third display component to light up or turn off. Thus, by using the different display states of the first, second, and third display components, different power supply wiring conditions can be detected, achieving the desired detection effect and effectively improving the accuracy of the detection. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0016] Figure 1 This is a power supply wiring detection circuit diagram in the embodiment.

[0017] Explanation of reference numerals in the attached figures

[0018] 1. Sampling module; 11. First sampling unit; 12. Second sampling unit; 2. Detection module; 21. First detection unit; 211. First display component; 212. Second display component; 213. First voltage divider component; 214. First current limiting component; 22. Second detection unit; 221. Third display component; 222. Second voltage divider component; 223. Second current limiting component. Detailed Implementation

[0019] The following drawings will disclose several embodiments of this utility model. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit this utility model. That is, in some embodiments of this utility model, these practical details are not essential. In addition, for the sake of simplicity, some conventional structures and components will be shown in the drawings in a simple schematic manner.

[0020] Furthermore, in this utility model, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the utility model. They are merely used to distinguish components or operations described with the same technical terms and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0021] Please refer to Figure 1 , Figure 1 Power connection detection circuit diagram. This embodiment provides a power connection detection circuit, which includes a sampling module 1 and a detection module 2. The sampling module 1 is used to connect to the live wire L, the neutral wire N, and the ground wire PE, and generates VL / PE and VN / PE signals respectively. Specifically, the sampling module 1 has a first input terminal, a second input terminal, a third input terminal, a first output terminal, and a second output terminal. The first input terminal of the sampling module 1 is connected to the live wire L, the second input terminal of the sampling module 1 is connected to the neutral wire N, and the third input terminal of the sampling module 1 is connected to the ground wire PE. The detection module 2 includes a first detection unit 21 and a second detection unit 22. The first detection unit 21 includes a comparator U1A, a first display component 211, and a second display component 212. The inverting input terminal of the comparator U1A is connected to the second output terminal of the sampling module 1, the non-inverting input terminal of the comparator U1A is connected to the reference voltage VCC, and the output terminal of the comparator U1A is connected to the first display component 211 and the second display component 212 respectively. The second detection unit 22 includes a comparator U1B and a third display component 221. The inverting input terminal of the comparator U1B is connected to the reference voltage VCC, the non-inverting input terminal of the comparator U1B is connected to the first output terminal of the sampling module 1, and the third display component 221 is connected to the output terminal of the comparator U1B.

[0022] When the live wire L and neutral wire L are normally connected to the circuit, there is a 220V voltage difference between the live wire L and the ground wire PE, and a 0V voltage difference between the neutral wire N and the ground wire PE. The inverting input of comparator U1A receives the electrical signal output from the second output of sampling module 1, and the non-inverting input receives the reference voltage VCC. Since the voltage output from the second output of sampling module 1 is lower than the reference voltage VCC, comparator U1A outputs a high level, at which point the first display component 211 is off, and the second display component 212 is on. The non-inverting input of comparator U1B receives the electrical signal output from the first output of sampling module 1, and the inverting input receives the reference voltage VCC. Since the voltage of the electrical signal output from the first output of sampling module 1 is greater than the reference voltage VCC, the output of comparator U1B outputs a low-high level signal, causing the third display component 221 to turn off.

[0023] When the live wire L and the neutral wire L are reversed, the voltage between the live wire L and the ground PE is 0V, and the voltage between the neutral wire N and the ground PE is 220V. At this time, the voltage output from the first output terminal of the sampling module 1 is higher than the reference voltage VCC, and the comparator U1A outputs a low level, causing the first display component 211 to light up and the second display component 212 to turn off. Since the voltage output from the second output terminal of the sampling module 1 is lower than the reference voltage VCC, the comparator U1B outputs a low level, and the third display component 221 lights up.

[0024] When the ground wire (PE) is not connected, there is no loop between the live wire (L) and the ground wire (PE), and there is no loop between the neutral wire (N) and the ground wire (PE). This results in the voltages of the electrical signals output from both the first and second output terminals of sampling module 1 being zero. Consequently, the voltage output from the first output terminal of sampling module 1 is lower than the reference voltage VCC, causing comparator U1A to output a high level. This causes the first display component 211 to turn off and the second component to turn on. Similarly, the voltage output from the second output terminal of sampling module 1 is lower than the reference voltage VCC, causing the third display component 221 to turn on.

[0025] Thus, by inputting the voltages of the first and second output terminals of sampling module 1 to comparators U1A and U1B respectively, comparator U1A compares the voltage output from the second output terminal of sampling module 1 with the reference voltage VCC, and comparator U1B compares the voltage output from the first output terminal of sampling module 1 with the reference voltage VCC. Then, a high or low level signal output from comparator U1A controls the first display component 211 and the second display component 212 to light up or turn off, and a high or low level signal output from comparator U1B controls the third display component 221 to light up or turn off. In this way, different power supply wiring conditions are detected through the different display states of the first display component 211, the second display component 212, and the third display component 221, achieving the detection effect and effectively improving the accuracy of the detection.

[0026] The first display component 211 includes a resistor R2 and a light-emitting diode D2. One end of the resistor R2 is connected to a reference voltage VCC, and the other end is connected to the positive terminal of the light-emitting diode D2. The resistor R2 is used for current limiting. The negative terminal of the light-emitting diode D2 is connected to the output terminal of the comparator U1A and the second display component 212.

[0027] When the voltage at the non-inverting input of comparator U1A is greater than the voltage at its inverting input, comparator U1A outputs a high-level signal, and LED D2 cannot be turned on. When the voltage at the non-inverting input of comparator U1A is less than the voltage at its inverting input, comparator U1A outputs a low-level signal, and LED D2 is turned on.

[0028] The second display component 212 includes a transistor Q1, a light-emitting diode D1, and a resistor R1. The base of transistor Q1 is connected to both the output of comparator U1A and the first display component 211. The emitter of transistor Q1 is grounded, the collector of transistor Q1 is connected to the cathode of light-emitting diode D1, the anode of light-emitting diode D1 is connected to one end of resistor R1, and the other end of resistor R1 is connected to a reference voltage VCC. Resistor R1 is used for current limiting.

[0029] When comparator U1A outputs a high-level signal, the base of transistor Q1 is at a high level, causing Q1 to conduct and LED D1 to light up. When comparator U1A outputs a low-level signal, the base of transistor Q1 is at a low level, preventing Q1 from conducting and thus LED D1 to turn off.

[0030] The third display component 221 includes a light-emitting diode D5 and a resistor R11. The negative terminal of the light-emitting diode D5 is connected to the output terminal of the comparator U1B, and the positive terminal of the light-emitting diode D5 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to the reference voltage VCC.

[0031] When the voltage at the non-inverting input of comparator U1B is greater than the voltage at its inverting input, comparator U1B outputs a high-level signal, and LED D5 cannot be turned on. When the voltage at the non-inverting input of comparator U1B is less than the voltage at its inverting input, comparator U1B outputs a low-level signal, and LED D5 is turned on.

[0032] Furthermore, the sampling module 1 includes a first sampling unit 11 and a second sampling unit 12. The first sampling unit 11 includes resistors R9 and R14, and a Zener diode D3. One end of resistor R9 serves as the first input terminal of the sampling module, connected to the live wire L. The other end of resistor R9 is connected to resistor R14 and Zener diode D3. The connection point between resistor R9, resistor R14, and Zener diode D3 serves as the first output terminal of the sampling module 1 and the non-inverting input terminal of the second detection unit 22. The other ends of resistor R14 and Zener diode D3 are grounded. The second sampling unit 12 includes resistors R10 and R15, and a Zener diode D4. One end of resistor R10 serves as the second input terminal, connected to the neutral wire N. The other end of resistor R10 is connected to resistor R15 and Zener diode D4. The connection point between resistor R10, resistor R15, and Zener diode D4 serves as the second output terminal of the sampling module 1 and is connected to the inverting input terminal of the first detection unit 21. The other ends of resistor R15 and Zener diode D4 are grounded. The sampling module 1 also includes a resistor R12, one end of which is grounded and the other end of which serves as the third input terminal of the sampling module 1 and is connected to the ground wire PE.

[0033] Resistors R9 and R14 are used to divide the voltage of the electrical signal input to the first input terminal of sampling module 1, and resistors R10 and R15 are used to divide the voltage of the electrical signal input to the second input terminal of sampling module 1. Zener diode D3 is used to bidirectionally clamp the voltage at the first output terminal, limiting the voltage to prevent damage to components in the circuit due to excessive voltage. Zener diode D4 is used to clamp the voltage output at the second output terminal, achieving the same effect as Zener diode D3, and will not be elaborated further here.

[0034] The first detection unit 21 also includes a first voltage divider component 213, which includes resistors R4 and R8. One end of resistor R4 is connected to the reference voltage VCC, and the other end is connected to the non-inverting input of comparator U1A and resistor R8, respectively. The other end of resistor R8 is grounded. Resistors R4 and R8 are used to divide the reference voltage VCC.

[0035] Similarly, the second detection unit 22 also includes a second voltage divider component 222, which includes resistors R13 and R20. One end of resistor R13 is connected to the reference voltage VCC, and the other end is connected to resistor R20 and the inverting input of comparator U1B, respectively. The other end of resistor R20 is grounded. Resistors R13 and R20 are used for voltage division.

[0036] The first detection unit 21 further includes a first current limiting component 214, which includes resistors R3 and R7. One end of resistor R3 is connected to the second output terminal of the sampling module 1, and the other end is connected to the inverting input terminal of comparator U1A. One end of resistor R7 is connected to the reference voltage VCC, and the other end is connected to the non-inverting input terminal of comparator U1A. Resistor R3 is used to limit the current of the electrical signal output from the second output terminal of the sampling module 1, and resistor R7 is used to limit the current of the input reference voltage VCC to protect comparator U1A.

[0037] The second detection unit 22 also includes a second current limiting component 223, which includes resistors R17 and R19. One end of resistor R17 is connected to the reference voltage VCC, and the other end is connected to the inverting input of comparator U1B. One end of resistor R19 is connected to the first output of sampling module 1, and the other end is connected to the non-inverting input of comparator U1B. Resistors R17 and R19 are used to protect the non-inverting and inverting inputs of comparator U1B to prevent excessive input current from damaging comparator U1B.

[0038] In addition, the first detection unit 21 also includes resistors R5 and R6. When connected, one end of resistor R6 is connected to the output terminal of comparator U1A, and the other end is connected to the first display component 211 and the second display component 212 respectively; one end of resistor R5 is connected to the reference voltage VCC, and the other end is connected to resistor R6, the first display component 211 and the second display component 212 respectively.

[0039] Resistor R6 is used for current limiting. The electrical signal output from the comparator U1A is limited by resistor R6 before being output to the first display component 211 and the second display component 212. Resistor R5 is used for current limiting of the first display component 211. Since excessive current will burn out the LED D2 when it is working, resistor R5 limits the current of LED D2 to ensure that LED D2 operates within a safe current range and avoids damage to components due to overcurrent.

[0040] The second detection unit 22 also includes resistors R18 and R16. One end of resistor R18 is connected to the output terminal of comparator U1B, and the other end is connected to resistor R16 and the third display component 221. The other end of resistor R16 is connected to the reference voltage VCC. Resistor R18 is used to shunt the electrical signal output from the output terminal of comparator U1B, and resistor R16 is used to shunt the third display component 221.

[0041] The above description is merely an embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this utility model should be included within the scope of the claims of this utility model.

Claims

1. A power supply wiring detection circuit, characterized in that, include: The sampling module (1) and the detection module (2) are provided. The sampling module (1) has a first input terminal, a second input terminal, a third input terminal, a first output terminal, and a second output terminal. The first input terminal of the sampling module (1) is connected to the live wire L, the second input terminal of the sampling module (1) is connected to the neutral wire N, and the third input terminal of the sampling module (1) is connected to the ground wire PE. The detection module (2) includes a first detection unit (21) and a second detection unit (22). The first detection unit (21) includes a comparator U1A, a first display component (211), and a second display component (212). The comparator U1A... The inverting input terminal of the comparator U1A is connected to the second output terminal of the sampling module (1), the non-inverting input terminal of the comparator U1A is connected to the reference voltage VCC, and the output terminal of the comparator U1A is connected to the first display component (211) and the second display component (212) respectively; the second detection unit (22) includes a comparator U1B and a third display component (221), the inverting input terminal of the comparator U1B is connected to the reference voltage VCC, the non-inverting input terminal of the comparator U1B is connected to the first output terminal of the sampling module (1), and the third display component (221) is connected to the output terminal of the comparator U1B.

2. The power supply wiring detection circuit according to claim 1, characterized in that, The sampling module (1) includes a first sampling unit (11) and a second sampling unit (12). The first sampling unit (11) includes a resistor R9, a resistor R14 and a Zener diode D3. One end of the resistor R9 is connected to the live wire L, and the other end of the resistor R9 is connected to the resistor R14, the Zener diode D3 and the non-inverting input terminal of the second detection unit (22). The other ends of the resistor R14 and the Zener diode D3 are grounded. The second sampling unit (12) includes a resistor R10, a resistor R15 and a Zener diode D4. One end of the resistor R10 is connected to the neutral wire N, and the other end of the resistor R15, the Zener diode D4 and the inverting input terminal of the first detection unit (21) are connected to the resistor R15 and the Zener diode D4. The other ends of the resistor R15 and the Zener diode D4 are grounded.

3. The power connection detection circuit according to claim 1, characterized in that, The first detection unit (21) further includes a first voltage divider component (213), which includes a resistor R4 and a resistor R8. One end of the resistor R4 is connected to the reference voltage VCC, and the other end is connected to the non-inverting input terminal of the comparator U1A and the resistor R8, respectively. The other end of the resistor R8 is grounded.

4. The power supply wiring detection circuit according to claim 1, characterized in that, The first detection unit (21) further includes a first current limiting component (214), which includes resistor R3 and resistor R7. One end of resistor R3 is connected to the second output terminal of the sampling module (1), and the other end is connected to the inverting input terminal of the comparator U1A. One end of resistor R7 is connected to the reference voltage VCC, and the other end is connected to the non-inverting input terminal of the comparator U1A.

5. The power supply wiring detection circuit according to claim 1, characterized in that, The first display component (211) includes a resistor R2 and a light-emitting diode D2. One end of the resistor R2 is connected to a reference voltage VCC, and the other end is connected to the positive terminal of the light-emitting diode D2. The negative terminal of the light-emitting diode D2 is connected to the output terminal of the comparator U1A and the second display component (212).

6. The power connection detection circuit according to claim 1, characterized in that, The second display component (212) includes a transistor Q1, a light-emitting diode D1, and a resistor R1; the base of the transistor Q1 is connected to the output terminal of the comparator U1A and the first display component (211), the emitter of the transistor Q1 is grounded, the collector of the transistor Q1 is connected to the negative terminal of the light-emitting diode D1, the positive terminal of the light-emitting diode D1 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to the reference voltage VCC.

7. The power supply wiring detection circuit according to claim 1, characterized in that, The third display component (221) includes a light-emitting diode D5 and a resistor R11. The negative terminal of the light-emitting diode D5 is connected to the output terminal of the comparator U1B, and the positive terminal of the light-emitting diode D5 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to the reference voltage VCC.

8. The power supply wiring detection circuit according to claim 1, characterized in that, The second detection unit (22) further includes a second voltage divider component (222), which includes a resistor R13 and a resistor R20. One end of the resistor R13 is connected to the reference voltage VCC, and the other end is connected to the resistor R20 and the inverting input terminal of the comparator U1B, respectively. The other end of the resistor R20 is grounded.

9. The power supply wiring detection circuit according to claim 1, characterized in that, The second detection unit (22) further includes a second current limiting component (223), which includes resistors R17 and R19. One end of resistor R17 is connected to the reference voltage VCC, and the other end is connected to the inverting input of the comparator U1B. One end of resistor R19 is connected to the first output of the sampling module (1), and the other end is connected to the non-inverting input of the comparator U1B.

10. The power supply wiring detection circuit according to claim 1, characterized in that, The first detection unit (21) also includes resistors R5 and R6. One end of resistor R6 is connected to the output terminal of comparator U1A, and the other end is connected to the first display component (211) and the second display component (212) respectively. One end of resistor R5 is connected to the reference voltage VCC, and the other end is connected to resistor R6, the first display component (211) and the second display component (212) respectively.

Images