Input circuit compatible with multiple voltage levels

Abstract

The utility model discloses a switching-in circuit compatible with multiple voltage levels, and effectively solves the problem that a protection device circuit is not suitable for different voltage levels. Comprising an input circuit which comprises an anode input port and a cathode input port; the resistance voltage division circuit comprises a positive voltage division resistor and a negative voltage division resistor; the level adjusting circuit comprises a linear voltage regulator, the linear voltage regulator comprises a voltage stabilizing input port, a voltage stabilizing output port and an adjusting port, the adjusting port is connected with a first adjusting resistor and a second adjusting resistor, one end of the first adjusting resistor is connected with the negative electrode input port, and the other end of the first adjusting resistor is connected with the negative electrode output port. One end of the second adjusting resistor is connected in parallel with the voltage stabilization output port; according to the utility model, the structure is ingenious, the use is convenient, through the arrangement of the jumper wire and the linear voltage regulator, not only can adjustment be carried out according to different voltage class inputs, the damage of high voltage to components be prevented, but also the versatility of the equipment circuit is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power distribution network, in particular to an open-in circuit compatible with multiple voltage levels. Background Art

[0002] The acquisition of input electrical signals is a function that secondary protection devices in the field of power distribution must have. The input circuit not only collects digital signals such as the on / off position of the circuit breaker, the energy storage status, and the non-electrical signal of the transformer, but also has to have certain high reliability, high speed and anti-interference functions.

[0003] Different voltage levels often require the input hardware of the device to be differentiated, which brings trouble to primary and secondary designers. Designers need to know the input level in advance, and once an error occurs and a mismatch occurs, it often leads to the device being returned to the factory for repair or the on-site power module being replaced.

[0004] In the Chinese patent application No. 202310795742.7, a switch quantity acquisition circuit for different voltage levels is disclosed, including two parallel current limiting branches, the input end of the current limiting branch is used to connect the input signal output interface end, each current limiting branch is provided with a current limiting resistor, and the resistance value of each current limiting resistor is different. Each current limiting branch is connected in series with a relay contact, wherein the current limiting resistor of the low voltage level is connected to the normally closed contact of the relay, and the current limiting resistor of the high voltage level is connected to the normally open contact of the relay. The coil part of the relay is arranged at the input signal output interface end, and one end of the coil part of the relay is also connected in series with a voltage divider resistor, which is used to energize / de-energize the coil part of the relay according to the voltage value of the input input signal, and control the contact action of the corresponding current limiting branch. The circuit can connect to two adaptive input signals of different voltage specifications. However, there are still some problems with this switch quantity acquisition circuit for different voltage levels:

[0005] 1. If 220V is turned on, during the process of 220V voltage falling back, there is a possibility that the voltage will fall back to 110V, and the contacts will jump multiple times.

[0006] 2. In actual application, according to the acquisition method of the open-in circuit, 220*0.3=66V, 110*0.7=77V, the controllable range between 66V and 77V is too narrow, and the application is limited. Utility Model Content

[0007] In view of the above situation, in order to overcome the defects of the prior art, the purpose of the present invention is to provide an open-in circuit compatible with multiple voltage levels, which effectively solves the problems mentioned in the background technology.

[0008] The technical solution is as follows: the utility model comprises:

[0009] An input circuit, the input circuit comprising a positive input port and a negative input port;

[0010] A resistor voltage divider circuit, the resistor voltage divider circuit comprising a positive voltage divider resistor and a negative voltage divider resistor;

[0011] A level adjustment circuit, the level adjustment circuit comprising a linear regulator, the linear regulator comprising a voltage stabilization input port, a voltage stabilization output port and an adjustment port, the adjustment ports are respectively connected to a first adjustment resistor and a second adjustment resistor, one end of the first adjustment resistor is connected to the negative input port, and one end of the second adjustment resistor is connected in parallel to the voltage stabilization output port;

[0012] An optocoupler circuit, the optocoupler circuit comprising an optocoupler, an input end of the optocoupler being connected in series with an input circuit;

[0013] A control circuit, wherein the control circuit comprises a CPU controller, and the output end of the optical coupler is connected to the control circuit;

[0014] The regulating circuit includes a jumper, a common end of the jumper is connected in series with the positive input port, four connection ports with different voltage levels are arranged on the jumper, the four connection ports are respectively connected with Zener diodes with different breakdown voltages, the four Zener diodes are connected in parallel with each other, and the four Zener diodes are respectively connected to the input end of the linear Zener diode.

[0015] Preferably, the output end of the optocoupler is connected to a power supply, and a pull-up resistor is provided between the power supply and the output end of the optocoupler.

[0016] Preferably, a shunt resistor and a transient suppression diode are respectively connected in parallel to the input end of the optical coupler.

[0017] Preferably, a surge protector is connected in parallel to the positive input port and the negative input port.

[0018] Preferably, a unidirectional diode is connected in series between the positive input port and the common end of the jumper.

[0019] Preferably, a bidirectional transient suppression diode is connected in parallel between the negative input port and the common end of the jumper.

[0020] Preferably, a capacitor is connected in parallel between the positive input port and the negative input port.

[0021] Compared with the prior art, the beneficial effects of the utility model are:

[0022] 1. Through the setting of jumpers and linear regulators, not only can the input be adjusted according to different voltage levels to prevent high voltage from damaging components, but also the versatility of the equipment circuit is improved.

[0023] 2. The level adjustment circuit of the protection device is compatible with input signals within 400V, so that the level adjustment circuit can stably output a constant level signal, ensuring that the subsequent optocoupler is not interfered by high-level signals during operation.

[0024] 3. In the switching of multiple voltage levels, there is no situation where high voltage drops back to low voltage, and the contacts will not jump multiple times. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a circuit diagram of the utility model.

[0026] Figure 2 It is a schematic diagram of the process of the utility model.

[0027] Explanation of the symbols in the schematic diagram:

[0028] 10. Input circuit; 11. Positive input port; 12. Negative input port; 20. Linear regulator; 21. Regulated input port; 22. Regulated output port; 23. Adjustment port; 30. First regulating resistor; 31. Second regulating resistor; 40. Optocoupler; 50. CPU controller; 60. Jumper; 70. Zener diode; 80. Power supply; 81. Pull-up resistor; 90. Surge protector; 91. Unidirectional diode; 92. Bidirectional transient suppression diode. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] Depend on Figure 1 to Figure 2 Given, including:

[0031] An input circuit 10, wherein the input circuit 10 comprises a positive input port 11 and a negative input port 12;

[0032] A resistor voltage divider circuit, wherein the resistor voltage divider circuit includes a positive voltage divider resistor and a negative voltage divider resistor. After the input circuit 10 is connected to a voltage signal within DC220V, it is connected to the linear voltage regulator 20 after passing through the positive voltage divider resistors R70 and R72 and the negative voltage divider resistors R71 and R73. The linear voltage regulator 20 outputs a constant voltage to the optical coupler 40. After the optical coupler 40 collects the signal, it is sent to the CPU controller 50, completing a whole open-in sampling loop;

[0033] A level adjustment circuit, wherein the level adjustment circuit includes a linear regulator 20, wherein the linear regulator 20 includes a voltage stabilization input port 21, a voltage stabilization output port 22 and an adjustment port 23, wherein the adjustment port 23 is respectively connected with a first adjustment resistor 30 and a second adjustment resistor 31, wherein one end of the first adjustment resistor 30 is connected with the negative input port 12, and one end of the second adjustment resistor 31 is connected in parallel with the voltage stabilization output port 22. It should be noted that the output voltage of the linear regulator 20 is determined by the proportional relationship between the first adjustment resistor 30 and the second adjustment resistor 31. In the present embodiment, the resistance value of the first adjustment resistor 30 is 18.2K, and the resistance value of the second adjustment resistor 31 is 6.04K. At this time, the constant voltage value output by the linear regulator 20 is 5V. When the output voltage of the linear regulator 20 needs to be adjusted, it is only necessary to pre-control the resistance value of the first adjustment resistor 30 to increase or decrease. At the same time, the first adjustment resistor 30 and the second adjustment resistor 31 both adopt a low temperature drift within 1% accuracy, thereby ensuring the stable output of the level of the linear regulator 20;

[0034] An optocoupler circuit, the optocoupler circuit comprising an optocoupler 40, an input end of the optocoupler 40 being connected in series with an input circuit 10;

[0035] A control circuit, wherein the control circuit comprises a CPU controller 50, and the output end of the optical coupler 40 is connected to the control circuit;

[0036] A regulating circuit, wherein the regulating circuit comprises a jumper 60, wherein a common end of the jumper 60 is connected in series with the positive input port 11, and the jumper 60 is provided with four connection ports of different voltage levels, wherein the four connection ports are respectively connected with zener diodes 70 of different breakdown voltages, wherein the four zener diodes 70 are connected in parallel with each other, and the four zener diodes 70 are respectively connected with the input end of the linear regulator 20;

[0037] In actual use, the power engineer adjusts the connection port of the jumper 60 according to the voltage level on site. The specific adjustment steps are as follows:

[0038] In order to prevent voltage signals of different voltage specifications from interfering with the circuit, the breakdown voltage needs to reach 30% of the voltage-stabilizing diode 70, but cannot exceed 60% or 70%. When the level signal is less than 30%, according to the characteristics of the voltage-stabilizing diode 70, the input circuit is in an open circuit state;

[0039] When the DC24V input circuit works normally, the input signal voltage passes through the resistor voltage divider circuit and is determined by the voltage level of the voltage regulator diode WY70, that is, after the DC24V voltage is passed, only the voltage regulator diode WY70 is broken down, and the conduction voltage of DC24V is selected to be 60%, so that the linear regulator 20 is turned on;

[0040] When the DC48V input circuit works normally, the input signal voltage passes through the resistor voltage divider circuit, and only the voltage regulator diode WY71 is broken down. The DC48V conduction voltage is selected to be 60%, so that the linear regulator 20 is turned on;

[0041] When the DC110V input circuit works normally, the input signal voltage passes through the resistor voltage divider circuit, the voltage regulator diode WY72 is broken down, and the linear regulator 20 is turned on;

[0042] When the DC220V input circuit works normally, the input signal voltage passes through the resistor voltage divider circuit, the voltage regulator diode WY73 is broken down, and the linear regulator 20 is turned on.

[0043] refer to Figure 1 As shown, the output end of the optocoupler 40 is connected to a power supply 80, and a pull-up resistor 81 is provided between the power supply 80 and the output end of the optocoupler 40. The power supply 80 prefabricates a high-level signal to the CPU controller 50. When the optocoupler 40 is not driven, this signal gives the CPU controller 50 a high-level signal that is not turned on. When the optocoupler 40 is driven, the output end of the optocoupler 40 is turned on, and the high-level signal is connected to the reference ground. This signal gives the CPU controller 50 a low-level signal that is turned on.

[0044] refer to Figure 1 As shown, the input end of the optocoupler 40 is respectively connected in parallel with a shunt resistor and a transient suppression diode, which can protect the interference signal in the level. If there is a reverse electromotive force at the input end of the optocoupler 40 (for example, a reverse spike voltage generated when the inductive load is disconnected), the transient suppression diode can provide reverse protection to prevent the reverse voltage from being too high and damaging the optocoupler 40. At the same time, the transient suppression diode can be used as a simple clamping circuit. When the input end of the optocoupler 40 is subjected to a reverse voltage impact, the diode is immediately turned on to limit the reverse voltage to below its reverse breakdown voltage, thereby protecting the optocoupler 40 from failure due to excessive reverse voltage.

[0045] refer to Figure 1 As shown, a surge protector 90 is connected in parallel to the positive input port 11 and the negative input port 12 to filter out strong electrical interference signals, discharge large energy interference sources in time, and protect the internal resistors and other components of the subsequent stage.

[0046] refer to Figure 1 As shown, a unidirectional diode 91 is connected in series between the positive input port 11 and the common end of the jumper 60 .

[0047] refer to Figure 1 As shown, a bidirectional transient suppression diode 92 is connected in parallel between the negative input port 12 and the common end of the jumper 60 .

[0048] refer to Figure 1As shown, a capacitor is connected in parallel between the positive input port 11 and the negative input port 12, which can effectively absorb high-frequency noise and interference pulses in the circuit as a filter element, reducing their impact on the input end of the optocoupler 40. At the same time, the optocoupler 40 itself has parasitic capacitance, especially in high-speed switching applications, which will affect the rising and falling edge speeds of the signal. Connecting a capacitor of appropriate size in parallel can compensate for the parasitic capacitance effect, speed up the switching speed of the optocoupler 40, and improve the response performance of the circuit.

[0049] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-voltage level compatible open-in circuit, characterized in that: include: An input circuit (10), the input circuit (10) comprising a positive input port (11) and a negative input port (12); A resistor voltage divider circuit, the resistor voltage divider circuit comprising a positive voltage divider resistor and a negative voltage divider resistor; A level adjustment circuit, the level adjustment circuit comprising a linear voltage regulator (20), the linear voltage regulator (20) comprising a voltage stabilization input port (21), a voltage stabilization output port (22) and an adjustment port (23), the adjustment port (23) being respectively connected to a first adjustment resistor (30) and a second adjustment resistor (31), one end of the first adjustment resistor (30) being connected to the negative input port (12), and one end of the second adjustment resistor (31) being connected in parallel to the voltage stabilization output port (22); An optocoupler circuit, the optocoupler circuit comprising an optocoupler (40), wherein an input end of the optocoupler (40) is connected in series with an input circuit (10); A control circuit, the control circuit comprising a CPU controller (50), and the output end of the optical coupler (40) is connected to the control circuit; A regulating circuit, the regulating circuit comprising a jumper (60), the common end of the jumper (60) being connected in series with a positive input port (11), the jumper (60) being provided with four connection ports of different voltage levels, the four connection ports being respectively connected with voltage stabilizing diodes (70) of different breakdown voltages, the four voltage stabilizing diodes (70) being connected in parallel with each other, and the four voltage stabilizing diodes (70) being respectively connected to the input end of a linear regulator (20).

2. The multi-voltage level compatible open-in circuit according to claim 1, characterized in that: The output end of the optical coupler (40) is connected to a power source (80), and a pull-up resistor (81) is provided between the power source (80) and the output end of the optical coupler (40).

3. The open-in circuit compatible with multiple voltage levels according to claim 1, characterized in that: The input end of the optical coupler (40) is respectively connected in parallel with a shunt resistor and a transient suppression diode.

4. The open-in circuit compatible with multiple voltage levels according to claim 1, characterized in that: A surge protector (90) is connected in parallel to the positive input port (11) and the negative input port (12).

5. The multi-voltage level compatible open-in circuit according to claim 1, characterized in that: A unidirectional diode (91) is connected in series between the positive input port (11) and the common end of the jumper (60).

6. The open-in circuit compatible with multiple voltage levels according to claim 1, characterized in that: A bidirectional transient suppression diode (92) is connected in parallel between the negative input port (12) and the common end of the jumper (60).

7. The open-in circuit compatible with multiple voltage levels according to claim 1, characterized in that: A capacitor is connected in parallel between the positive input port (11) and the negative input port (12).

Images