Power supply reverse connection alarm circuit

Abstract

The utility model provides a power supply reverse connection alarm circuit, which comprises a current detection module and a control module, the input end of the current detection module is connected with the positive and negative electrodes of a load power supply, the signal output end of the current detection module is connected with the control module, and the control module is in communication connection with an upper computer. And the control module is used for receiving the signal sent by the current detection module and judging whether the load power supply is reversely connected or not, and sending an alarm signal to the upper computer when judging that the load power supply is reversely connected. According to the power supply reverse connection alarm circuit provided by the utility model, an alarm can be timely given to an upper computer through the control module when a load power supply is reversely connected, the number of elements used by the power supply reverse connection alarm circuit is small, the cost is reduced, the circuit size can be effectively reduced, and the applicability is improved; damage to the load and peripheral equipment caused by reverse connection of the load power supply is effectively avoided, the service life of the load and the peripheral equipment is prolonged, and the equipment reliability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, in particular to a power reverse connection alarm circuit. Background Art

[0002] When installing equipment on industrial sites, reverse power connection can occur, causing load short circuits and overcurrent, impacting the safety and proper operation of the load and surrounding equipment. Currently, common reverse power connection alarm devices contain numerous circuit components, resulting in increased cost, bulk, and poor applicability. Utility Model Content

[0003] The purpose of the utility model is to provide a power reverse connection alarm circuit, which can solve one or more of the above-mentioned problems in the prior art.

[0004] According to one aspect of the present invention, a power reverse connection alarm circuit is provided, including a current detection module and a control module, the input end of the current detection module is connected to the positive and negative poles of the load power supply, the signal output end of the current detection module is connected to the control module, the control module is connected to the host computer for communication, the control module is used to receive the signal sent by the current detection module and judge whether the load power supply is reversed, and when it is judged that the load power supply is reversed, an alarm signal is sent to the host computer; the current detection module includes a photocoupler U2 and a dual operational amplifier, the output end of the photocoupler U2 is connected to the signal input end of the control module, the input end of the photocoupler U2 is connected to the output end of the dual operational amplifier, and the non-inverting input end of the dual operational amplifier is connected to the positive pole of the load power supply through the fuse F1.

[0005] In some embodiments, the control module is a single chip microcomputer.

[0006] In some embodiments, the output end of the optocoupler U2 is connected to the power supply end of the control module through the resistor R2, the positive input end of the optocoupler U2 is connected to the DC voltage, and the negative input end of the optocoupler U2 is connected to the output end of the dual operational amplifier.

[0007] In some embodiments, the dual operational amplifier includes an operational amplifier U3A and an operational amplifier U3B, the input end of the optocoupler U2 is connected to the output end of the operational amplifier U3A, and the non-inverting input end of the operational amplifier U3B is connected to the positive pole of the load power supply through the fuse F1.

[0008] In some embodiments, the positive power input terminal of the operational amplifier U3A is connected to a DC voltage, the negative power input terminal of the operational amplifier U3A is grounded, the non-inverting input terminal of the operational amplifier U3A is connected to a DC voltage, and the inverting input terminal of the operational amplifier U3A is connected to the output terminal of the operational amplifier U3B.

[0009] In some embodiments, a capacitor C1, a three-terminal adjustable shunt regulator U1, and a resistor R1 are connected between the non-inverting input terminal of the operational amplifier U3A and the DC voltage, the two ends of the resistor R1 are respectively connected to the non-inverting input terminal of the operational amplifier U3A and the DC voltage, one end of the capacitor C1 is connected to the non-inverting input terminal of the operational amplifier U3A, and the other end is grounded, the reference terminal R and the cathode K of the three-terminal adjustable shunt regulator U1 are respectively connected to the non-inverting input terminal of the operational amplifier U3A, and the anode A of the three-terminal adjustable shunt regulator U1 is grounded.

[0010] In some embodiments, the non-inverting input terminal of the operational amplifier U3B is connected to the positive electrode of the load power supply through the resistor R5 and the fuse F1, and the non-inverting input terminal of the operational amplifier U3B is grounded through the resistor R8; the inverting input terminal of the operational amplifier U3B is connected to the output terminal of the operational amplifier U3B through the resistor R9, and the positive electrode of the load power supply is connected to the fuse F1 and the sampling resistor R6 in sequence before outputting a DC voltage.

[0011] In some embodiments, the resistance values ​​of the resistor R5 and the resistor R7 are equal; the resistance values ​​of the resistor R8 and the resistor R9 are equal.

[0012] In some embodiments, when the load power supply is 24V, the positive electrode of the load power supply is connected to the fuse F1 and the sampling resistor R6 in sequence, and the output DC voltage is 24V.

[0013] The power reverse connection alarm circuit provided by the utility model can promptly alarm the upper computer through the control module when the load power is reversed. The power reverse connection alarm circuit uses a small number of components, which reduces costs and can effectively reduce the circuit volume and improve applicability. It can effectively avoid damage to the load and peripheral equipment caused by reverse connection of the load power, extend the service life of the load and peripheral equipment, and improve equipment reliability.

[0014] In addition, in the technical solution of the present utility model, anything not specifically described can be implemented by adopting conventional means in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, a brief introduction will be given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 This is a structural diagram of a power reverse connection alarm circuit provided by one embodiment of the utility model.

[0017] Figure 2This is a circuit diagram of a current detection module provided in one embodiment of the present utility model.

[0018] Figure 3 This is a circuit diagram of a control module provided in one embodiment of the present utility model. DETAILED DESCRIPTION

[0019] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0020] Example:

[0021] In this embodiment, refer to the attached manual. Figure 1-3 , provides a power reverse connection alarm circuit, including a current detection module 1 and a control module 2.

[0022] The input end of the current detection module 1 is connected to the positive and negative poles of the load power supply 3, the signal output end of the current detection module 1 is connected to the control module 2, the control module 2 is communicated with the host computer 4, and the control module 2 is used to receive the signal sent by the current detection module 1 and judge whether the load power supply 3 is reversely connected. When it is judged that the load power supply 3 is reversely connected, an alarm signal is sent to the host computer 4.

[0023] The positive electrode of the load power supply 3 is represented by OVCC, and the negative electrode of the load power supply 3 is represented by OGND.

[0024] The current detection module 1 includes a photocoupler U2 and a dual operational amplifier. The output end of the photocoupler U2 is connected to the signal input end of the control module 2, the input end of the photocoupler U2 is connected to the output end of the dual operational amplifier, and the non-inverting input end of the dual operational amplifier is connected to the positive pole of the load power supply 3 through the fuse F1.

[0025] The control module 2 may be a single-chip microcomputer. Specifically, the control module 2 may be a single-chip microcomputer of the STM32 series. In this embodiment, a single-chip microcomputer of the STM32F103C8T type is selected.

[0026] The photocoupler U2 in the current detection module 1 is a photocoupler of model EL3H7(C)(TA)-G.

[0027] The output end of the photocoupler U2 is connected to the power supply end of the control module 2 through the resistor R2, the positive input end of the photocoupler U2 is connected to the DC voltage, and the negative input end of the photocoupler U2 is connected to the output end of the dual operational amplifier.

[0028] The dual operational amplifier can be a dual operational amplifier of model LM358. The dual operational amplifier includes operational amplifier U3A and operational amplifier U3B. The output voltage of operational amplifier U3A is recorded as V out2 , the output voltage of the operational amplifier U3B is recorded as V out1 The input end of the photocoupler U2 is connected to the output end of the operational amplifier U3A, and the non-inverting input end of the operational amplifier U3B is connected to the positive electrode of the load power supply 3 through the fuse F1.

[0029] The positive power input terminal of the operational amplifier U3A is connected to a DC voltage, the negative power input terminal of the operational amplifier U3A is grounded, the non-inverting input terminal of the operational amplifier U3A is connected to a DC voltage, and the inverting input terminal of the operational amplifier U3A is connected to the output terminal of the operational amplifier U3B.

[0030] Capacitor C1, three-terminal adjustable shunt regulator U1 and resistor R1 are connected between the non-inverting input terminal of the operational amplifier U3A and the DC voltage. The two ends of the resistor R1 are respectively connected to the non-inverting input terminal of the operational amplifier U3A and the DC voltage. One end of the capacitor C1 is connected to the non-inverting input terminal of the operational amplifier U3A, and the other end is grounded. The reference terminal R and cathode K of the three-terminal adjustable shunt regulator U1 are respectively connected to the non-inverting input terminal of the operational amplifier U3A, and the anode A of the three-terminal adjustable shunt regulator U1 is grounded.

[0031] Fuse F1 can be selected with a holding current of 5A and a tripping current of 10A.

[0032] The non-inverting input terminal of the operational amplifier U3B is connected to the positive electrode of the load power supply 3 through the resistor R5 and the fuse F1, and the non-inverting input terminal of the operational amplifier U3B is grounded through the resistor R8; the inverting input terminal of the operational amplifier U3B is connected to the output terminal of the operational amplifier U3B through the resistor R9, and the positive electrode of the load power supply 3 is connected to the fuse F1 and the sampling resistor R6 in sequence to output a DC voltage.

[0033] The resistance values ​​of the resistor R5 and the resistor R7 are equal; the resistance values ​​of the resistor R8 and the resistor R9 are equal.

[0034] When the load power supply 3 is 24V, the positive electrode of the load power supply 3 is connected to the fuse F1 and the sampling resistor R6 in sequence, and the output DC voltage is 24V.

[0035] The following is attached with the instruction manual Figure 2The parameters recorded in the example are used to illustrate the detection and alarm process of the power reverse connection alarm circuit provided by the utility model. The current passing through the sampling resistor R6 is recorded as I, and the output voltage of the operational amplifier U3A is recorded as V out2 , the output voltage of the operational amplifier U3B is recorded as V out1 , V out1 =I*(R9*R6) / R5.

[0036] When V out1 =2.5V, the calculated value is I = 5.8A. When the load power supply 3 is reversely connected, the current I becomes larger. When the current I is greater than 5.8A, V out1 >2.5V, V out2 =0V, at this time the signal FAULT output by the current detection module 1 is low level, when the current I is not greater than 5.8A, V out1 <2.5V, V out2 =24V, at this time the signal FAULT output by the current detection module 1 is high level.

[0037] The control module 2 receives the signal output by the current detection module 1. When FAULT is at a low level, the control module 2 determines that the current load power supply is reversed and sends an alarm to the upper computer 4. The upper computer 4 can issue an alarm to the operator through its operation page, prompting that the load is overcurrent and it is necessary to check whether the load power supply is reversed.

[0038] The power reverse connection alarm circuit provided by the utility model can promptly alarm the upper computer through the control module when the load power is reversed. The power reverse connection alarm circuit uses a small number of components, which reduces costs and can effectively reduce the circuit volume and improve applicability. It can effectively avoid damage to the load and peripheral equipment caused by reverse connection of the load power, extend the service life of the load and peripheral equipment, and improve equipment reliability.

[0039] The above is only an optional implementation of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. The power reverse connection alarm circuit is characterized by: It includes a current detection module (1) and a control module (2), The input end of the current detection module (1) is connected to the positive and negative electrodes of the load power supply (3), and the signal output end of the current detection module (1) is connected to the control module (2). The control module (2) is communicatively connected to a host computer (4), and the control module (2) is used to receive a signal sent by the current detection module (1) and to determine whether the load power supply (3) is reversely connected. When it is determined that the load power supply (3) is reversely connected, an alarm signal is sent to the host computer (4); The current detection module (1) comprises a photoelectric coupler U2 and a dual operational amplifier, wherein the output end of the photoelectric coupler U2 is connected to the signal input end of the control module (2), the input end of the photoelectric coupler U2 is connected to the output end of the dual operational amplifier, and the non-inverting input end of the dual operational amplifier is connected to the positive electrode of the load power supply (3) via a fuse F1.

2. The power reverse connection alarm circuit according to claim 1, characterized in that: The control module (2) is a single chip microcomputer.

3. The power reverse connection alarm circuit according to claim 1, characterized in that: The output end of the photoelectric coupler U2 is connected to the power supply end of the control module (2) through a resistor R2, the positive input end of the photoelectric coupler U2 is connected to a DC voltage, and the negative input end of the photoelectric coupler U2 is connected to the output end of the dual operational amplifier.

4. The power reverse connection alarm circuit according to claim 1, characterized in that: The dual operational amplifier comprises an operational amplifier U3A and an operational amplifier U3B, the input end of the photoelectric coupler U2 is connected to the output end of the operational amplifier U3A, and the non-inverting input end of the operational amplifier U3B is connected to the positive electrode of the load power supply (3) through a fuse F1.

5. The power reverse connection alarm circuit according to claim 4, characterized in that: The positive power input terminal of the operational amplifier U3A is connected to a DC voltage, the negative power input terminal of the operational amplifier U3A is grounded, the non-inverting input terminal of the operational amplifier U3A is connected to a DC voltage, and the inverting input terminal of the operational amplifier U3A is connected to the output terminal of the operational amplifier U3B.

6. The power reverse connection alarm circuit according to claim 4, characterized in that: A capacitor C1, a three-terminal adjustable shunt regulator U1 and a resistor R1 are connected between the non-inverting input terminal of the operational amplifier U3A and the DC voltage. The two ends of the resistor R1 are respectively connected to the non-inverting input terminal of the operational amplifier U3A and the DC voltage. One end of the capacitor C1 is connected to the non-inverting input terminal of the operational amplifier U3A, and the other end is grounded. The reference terminal R and cathode K of the three-terminal adjustable shunt regulator U1 are respectively connected to the non-inverting input terminal of the operational amplifier U3A, and the anode A of the three-terminal adjustable shunt regulator U1 is grounded.

7. The power reverse connection alarm circuit according to claim 4, characterized in that: The non-inverting input terminal of the operational amplifier U3B is connected to the positive electrode of the load power supply (3) through the resistor R5 and the fuse F1, and the non-inverting input terminal of the operational amplifier U3B is grounded through the resistor R8; The inverting input terminal of the operational amplifier U3B is connected to the output terminal of the operational amplifier U3B via a resistor R9. The positive electrode of the load power supply (3) is connected to the fuse F1 and the sampling resistor R6 in sequence to output a DC voltage.

8. The power reverse connection alarm circuit according to claim 7, characterized in that: The resistance values ​​of the resistor R5 and the resistor R7 are equal; the resistance values ​​of the resistor R8 and the resistor R9 are equal.

9. The power reverse connection alarm circuit according to claim 7, characterized in that: When the load power supply (3) is 24V, the positive electrode of the load power supply (3) is connected to the fuse F1 and the sampling resistor R6 in sequence, and the output DC voltage is 24V.

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