Input adaptive circuit, circuit board and relay protection tester
By designing an open-in adaptive circuit, the path module and the optocouple output module are used to achieve compatibility with multiple open-in quantities, and the power consumption is reduced through reasonable selection of current limiting resistors, the problem of the incoming circuit in the prior art is not compatible with a variety of open-in quantities and high resistance power consumption, and the circuit is realized for a long time and stable operation.
Patent Information
- Application Number
- CN202411645307.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-03-25
AI Technical Summary
The opening and inlet circuit of existing relay protection testers cannot be compatible with multiple output types at the same time, and the resistance power consumption is high when input at high voltage, resulting in serious heat generation and affecting the circuit's long-term operation.
An open-in capacity adaptive circuit is designed, and the optocouple output module is provided with corresponding input loops through the first path module and the second path module to achieve compatibility with DC or AC active and passive openings, and to reduce power consumption through reasonable selection of current limiting resistors.
Compatibility with multiple output types is achieved, circuit power consumption is reduced, serious problem of resistance heating is avoided, and the operation time of the circuit is extended.
Smart Images
Figure CN119696566A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of electronic circuits, and in particular to a binary input adaptive circuit, a circuit board and a relay protection tester. Background Art
[0002] In a relay protection tester, the input circuit is generally used to receive the output of the relay protection device and reflect its status. Since different types of relay protection devices and in different working environments may have different output interface types, such as the output interface type usually has two major categories (such as the active type corresponding to the active output and the passive type corresponding to the passive output), if the input circuit of the relay protection tester does not match the output interface type of the relay protection device, it may cause the relay protection tester to not work properly and may also cause damage to the relay protection tester.
[0003] In the related art, many tester input circuits cannot be compatible with multiple output types at the same time, such as supporting only a single active type and a passive type, or the active type has a narrow voltage range and only supports DC input, etc. Moreover, when there is an active input, when the input voltage is too high, a large power consumption will be generated on the resistor in the circuit, causing the resistor to have a serious heating problem, which is not conducive to the long-term operation of the circuit. Summary of the invention
[0004] The present application provides a binary input adaptive circuit, a circuit board and a relay protection tester, which solve the technical problem in the related art that the binary input circuit is not compatible with active and passive. The present solution can be compatible with DC or AC active binary inputs and passive binary inputs, and the circuit power consumption is low.
[0005] In a first aspect, the present application provides a binary input adaptive circuit, which includes a first resistor, a second resistor, an optocoupler output module, a first path module, and a second path module.
[0006] Among them, one end of the first resistor is connected to the first input terminal, and the first input terminal is used to connect the active binary input or the passive binary input; one end of the second resistor is connected to the second input terminal, and the other end of the second resistor is grounded, and the second input terminal is used to connect the active binary input or the passive binary input;
[0007] The first output end of the optocoupler output module is connected to the output terminal. The optocoupler output module is used to feed back to the subsequent circuit a binary input signal indicating that an active binary input quantity or a passive binary input quantity is currently connected when the second output end of the optocoupler output module is connected to a conduction voltage.
[0008] The first output end of the first path module is connected to the other end of the first resistor, the second output end of the first path module is connected to the other end of the second resistor, and the input end of the first path module is connected to the second output end of the optocoupler output module. When the first input terminal is connected to a negative active binary input and the second input terminal is connected to a positive active binary input, or when the first input terminal and the second input terminal are connected to a passive binary input, the first path module is turned on.
[0009] The first input end of the second path module is connected to the other end of the first resistor, the second input end of the second path module is connected to the second output end of the optocoupler output module, and the output end of the second path module is connected to the other end of the second resistor. When the first input terminal is connected to a positive active open input and the second input terminal is connected to a negative active open input, the second path module is turned on.
[0010] In a second aspect, the present application further provides a circuit board, which includes the open-input adaptive circuit provided in the first aspect.
[0011] In a third aspect, the present application also provides a relay protection tester, which includes a circuit board as provided in the second aspect.
[0012] The adaptive input circuit of the present application provides a corresponding input circuit for the optocoupler output module through the first path module and the second path module, and then drives the optocoupler output module by turning on the corresponding input circuit, thereby achieving compatibility with active AC and DC inputs and passive inputs, thereby matching various types of outputs, which helps to expand the scope of use of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 A principle block diagram of a binary input adaptive circuit provided in one embodiment of the present application;
[0014] Figure 2 A schematic diagram of the circuit structure of an optocoupler output module provided in one embodiment of the present application;
[0015] Figure 3 A schematic diagram of the circuit structure of a first path module provided in one embodiment of the present application;
[0016] Figure 4 A schematic diagram of the circuit structure of a second path module provided in one embodiment of the present application;
[0017] Figure 5 A schematic diagram of the circuit structure of a binary input adaptive circuit provided in one embodiment of the present application. DETAILED DESCRIPTION
[0018] The embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are only used to explain the embodiments of the present application, rather than to limit the embodiments of the present application. It should also be noted that, for ease of description, only the parts related to the embodiments of the present application rather than all structures are shown in the accompanying drawings, and those skilled in the art should be able to think of it after reading the specification of this application that as long as the technical features do not contradict each other, any combination of the technical features can constitute an optional implementation method.
[0019] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable when appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally a class, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally represents that the objects associated before and after are in an "or" relationship. In the description of the present application, "multiple" means two or more, and "several" means one or more.
[0020] In a relay protection tester, the binary input circuit is generally used to receive the binary output of the relay protection device. At present, the binary input circuits of many relay protection testers are not compatible with multiple binary output types at the same time, such as only supporting a single active type and a passive type, or the active type has a narrow voltage range and only supports DC input. If the binary input circuit of the relay protection tester does not match the binary output interface type of the relay protection device, the relay protection tester may not work properly and may also be damaged.
[0021] It is understandable that passive switching outputs can be divided into: relay contact type passive switching outputs and transistor type high-speed passive switching outputs. Active switching outputs can be divided into: DC active switching outputs and AC active switching outputs. In the related technology, there are also some tester input circuits that can be compatible with active and passive AC and DC wide voltage inputs at the same time, but their solutions have some obvious disadvantages, such as the selection of current limiting resistors under wide voltage active switching conditions, which can easily lead to large power consumption on the resistors in the circuit when the input voltage is too high, causing serious heating of the resistors, which is not conducive to long-term operation of the circuit.
[0022] In addition, in the related art, when the input signal is used to directly drive the optocoupler in the active input mode, it is difficult to select the current limiting resistor of the input circuit while being compatible with a wide voltage range of 24V to 250V. When the resistance value of the current limiting resistor is selected to be larger, the input circuit current is too small when the input voltage is low, and it is difficult to drive the optocoupler to work stably; when the resistance value of the current limiting resistor is selected to be smaller, the input circuit current is too large when the input voltage is high, resulting in greater power consumption on the current limiting resistor, and higher requirements on the resistor power.
[0023] In this regard, the embodiment of the present application provides a binary input adaptive circuit, which is compatible with DC or AC active binary inputs and passive binary inputs, and has low circuit power consumption. Figure 1 As shown, Figure 1 The principle block diagram of the binary input adaptive circuit provided in one embodiment of the present application, the binary input adaptive circuit includes a first resistor, a second resistor, an optocoupler output module 110, a first path module 120 and a second path module 130. The ground is marked with a triangle symbol in the figure. In the binary input adaptive circuit, the first resistor is connected to the first input terminal, the second resistor is connected to the second input terminal, and the first output end of the optocoupler output module 110 is connected to the output terminal, wherein the first input terminal and the second input terminal are both used as input terminals of the binary input adaptive circuit, and are used to connect active binary input or passive binary input. For example, when connecting an active binary input, for a positive binary input voltage, the first input terminal is equivalent to connecting to the positive pole of the power supply, and the second input terminal is equivalent to connecting to the negative pole of the power supply.
[0024] The second output end of the optocoupler output module 110 is connected to the first path module 120 and the second path module 130. Specifically, the first output end of the first path module 120 is connected to the other end of the first resistor, and the second output end of the first path module 120 is connected to the other end of the second resistor, and the other end of the second resistor is grounded. The second output end of the first path module 120 is also grounded. Therefore, the optocoupler output module 110 can form an input loop through the first path module 120, the first resistor and the second resistor. When the input loop is turned on, the second output end of the optocoupler output module 110 is equivalent to the connected conduction voltage, and then the optocoupler output module 110 can feedback to the subsequent circuit through its first output end a binary input signal indicating that an active binary input or a passive binary input is currently connected.
[0025] When the first input terminal is connected to a negative active binary input and the second input terminal is connected to a positive active binary input, the first path module 120 is turned on; in addition, when the first input terminal and the second input terminal are connected to a passive binary input, that is, the first input terminal and the second input terminal are short-circuited, the first path module 120 is also turned on. It can be imagined that when the first path module 120 is turned on, the above-mentioned input circuit is turned on.
[0026] The first input end of the second path module 130 is connected to the other end of the first resistor, the second input end of the second path module 130 is connected to the second output end of the optocoupler output module 110, and the output end of the second path module 130 is connected to the other end of the second resistor. It can be imagined that the other end of the second resistor is grounded, and the output end of the second path module 130 is also grounded. Therefore, the optocoupler output module 110 can also form another input loop through the second path module 130, the first resistor and the second resistor. When the input loop is turned on, the second output end of the optocoupler output module 110 is equivalent to the access to the turn-on voltage, and then the optocoupler output module 110 can feedback the open-in signal to the subsequent circuit through the first output end thereon.
[0027] When the first input terminal is connected to a positive active input and the second input terminal is connected to a negative active input, the second path module 130 is turned on. When the second path module 130 is turned on, the other input loop is also turned on.
[0028] It can be understood that the circuit forms an electrically isolated input mode through the optocoupler output module 110, and the first resistor and the second resistor are both used as current-limiting resistors in the input circuit. When an active binary input (DC or AC) is connected, from the first input terminal, when a positive active binary input is connected, the second path module 130 is turned on, thereby providing a conductive input circuit for the optocoupler output module 110, and then providing a corresponding binary input signal for the subsequent signal; when a negative active binary input is connected, the first path module 120 is turned on, thereby providing another conductive input circuit for the optocoupler output module 110, and then providing a corresponding binary input signal for the subsequent signal. When a passive binary input is connected, the first path module 120 is turned on, providing another conductive input circuit for the optocoupler output module 110, and then providing a corresponding binary input signal for the subsequent signal.
[0029] It can be seen from the above scheme that the adaptive input circuit of the present application provides a corresponding input circuit for the optocoupler output module through the first path module and the second path module, and then drives the optocoupler output module by turning on the corresponding input circuit, thereby achieving compatibility with active AC and DC inputs and passive inputs, thereby matching various types of outputs, which helps to expand the scope of use of the circuit.
[0030] In some embodiments, the optocoupler output module includes a photocoupler, a third resistor and a first capacitor, wherein the transmitting anode terminal of the photocoupler is connected to the working voltage, the transmitting cathode terminal of the photocoupler serves as the second output terminal of the optocoupler output module, the receiving collector terminal of the photocoupler is connected to the external voltage, the receiving emitter terminal of the photocoupler is connected to the grounded third resistor, the first capacitor is connected in parallel to the third resistor, and the receiving emitter terminal of the photocoupler serves as the first output terminal of the optocoupler output module and is connected to the output terminal.
[0031] It can be understood that in the optocoupler output module, an input loop is formed on one side of the transmitting anode terminal and the transmitting cathode terminal, and then when the transmitting cathode terminal is connected to any conductive first path module or second path module, the input loop is turned on, and then the optocoupler is turned on, so that the receiving emitter terminal on it can provide an open-in signal to the subsequent circuit. It can be imagined that the first capacitor and the third resistor form an RC filter circuit, which can filter out interference in the open-in signal and stabilize the output of the optocoupler.
[0032] In one embodiment, the optocoupler output module also includes a power isolation unit, which isolates the interference of the external power supply through the power isolation unit, realizes electrical isolation and can also provide a working voltage for the circuit. For example, the power isolation unit includes a DCDC converter, a second capacitor and a third capacitor, wherein the input end of the DCDC converter is connected to the external power supply, and the input end of the DCDC converter is connected to the grounded second capacitor, the output end of the DCDC converter is used to provide a working voltage for the circuit, and the output end of the DCDC converter is connected to the grounded third capacitor. In this regard, the second capacitor and the third capacitor are respectively used to filter out the ripples on the input and output ends of the DCDC converter, thereby stabilizing the input voltage and stabilizing the output voltage.
[0033] For example, Figure 2 A schematic diagram of the circuit structure of an optocoupler output module provided in an embodiment of the present application, as shown in the figure, in one embodiment, the optocoupler output module includes a photocoupler U1, a third resistor R3, a first capacitor C1, a second capacitor C2, a third capacitor C3 and a DCDC converter U2, specifically, the emission anode end of the photocoupler U1 is connected to the working voltage, the receiving collector end of the photocoupler U1 is connected to the external voltage, the receiving emitter end of the photocoupler U1 is connected to the grounded third resistor R3, the first capacitor C1 is connected in parallel to the third resistor R3, the input end of the DCDC converter U2 is connected to the external power supply, the input end of the DCDC converter U2 is connected to the grounded second capacitor C2, the output end of the DCDC converter U2 is connected to the grounded third capacitor C3, and the output end of the DCDC converter U2 is used to provide the circuit with a working voltage. Therefore, the circuit can achieve electrical isolation input through the optocoupler output module, thereby providing a stable signal level for the signal output, which helps to maintain the stable operation of the circuit.
[0034] It should be noted that, in some embodiments, the power isolation unit may also use an isolated DCDC circuit such as a DCM flyback converter circuit, a single-switch forward converter circuit, etc. to achieve electrical isolation between the external power supply and the circuit load.
[0035] Figure 3 A schematic diagram of the circuit structure of a first path module provided in an embodiment of the present application. In one embodiment, as Figure 3 As shown, the first path module includes a fourth resistor R4, a fifth resistor R5, a first diode D1 and a PNP transistor Q1.
[0036] Among them, the emitter end of the PNP transistor Q1 serves as the output end of the first path module, the base end of the PNP transistor Q1 is connected to the emitter end of the PNP transistor Q1 through the fourth resistor R4, the base end of the PNP transistor Q1 is also connected to the anode end of the first diode D1, the cathode end of the first diode D1 serves as the first output end of the first path module, the collector end of the PNP transistor Q1 is connected to the first end of the fifth resistor R5, and the second end of the fifth resistor R5 serves as the second output end of the first path module.
[0037] It is understandable that the first diode D1 is connected in reverse to protect the PNP transistor Q1 from being damaged by reverse voltage. The PNP transistor Q1 serves as the conduction switch of the first path module, and the input quantity can be used as the conduction trigger signal of the PNP transistor Q1. When the PNP transistor Q1 is turned on, the fifth resistor R5 plays a role of current limiting. The fourth resistor R4 serves as a bypass resistor of the PNP transistor Q1 to prevent the transistor from being mis-conducted.
[0038] When a negative voltage is connected, that is, the input voltage is negative, current flows in from the first input terminal. At this time, the PNP transistor Q1 meets the conduction condition, and the PNP transistor Q1 is turned on. After it is turned on, the input circuit of the optocoupler output module is turned on, that is, the current can flow into the ground terminal after passing through the PNP transistor Q1, the first diode D1, the first resistor, the first input terminal, the second input terminal, and the second resistor, so that the input circuit is turned on. Since the PNP transistor Q1 has a current amplification function, the trigger circuit current can be as low as uA (microampere) level and can still normally trigger the input circuit of the optocoupler output module to turn on, so as to achieve normal output of the signal.
[0039] Similarly, when the passive input is connected, the first input terminal and the second input terminal are short-circuited, and the current can flow into the ground terminal after passing through the PNP transistor Q1, the first diode D1, the first resistor, the first input terminal, the second input terminal, and the second resistor, thereby making the input loop conductive.
[0040] Therefore, through the first path module, the binary input adaptive circuit can still respond to the triggering of the binary input when the voltage is small and the loop current is small, thereby making the input loop of the optocoupler output module conductive, thereby realizing the normal output of the signal, and can also adapt to the access of active binary inputs and passive binary inputs, thereby expanding the scope of use of the circuit and realizing the adaptation of the binary inputs.
[0041] Figure 4 This is a circuit structure diagram of a second path module provided in an embodiment of the present application. In one embodiment, as shown in the figure, the second path module includes a sixth resistor R6, a seventh resistor R7, a second diode D2, a voltage regulator diode D3 and an NPN transistor Q2.
[0042] Among them, the collector end of the NPN transistor Q2 is connected to the first end of the sixth resistor R6, and the second end of the sixth resistor R6 serves as the second input end of the second path module; the base end of the NPN transistor Q2 is connected to the anode end of the Zener diode D3, the cathode end of the Zener diode D3 is connected to the cathode end of the second diode D2, and the anode end of the second diode D2 serves as the first input end of the second path module; the base end of the NPN transistor Q2 is also connected to the emitter end of the NPN transistor Q2 through the seventh resistor R7, and the emitter end of the NPN transistor Q2 is grounded.
[0043] It is understandable that the second diode D2 is connected in reverse to protect the NPN transistor Q2 from being damaged by reverse voltage. The NPN transistor Q2 serves as the conduction switch of the second path module, and the input quantity can be used as the conduction trigger signal of the NPN transistor Q2. When the NPN transistor Q2 is turned on, the sixth resistor R6 plays a role of current limiting. The seventh resistor R7 serves as a bypass resistor of the NPN transistor Q2 to prevent the transistor from being mis-conducted. The voltage regulator diode D3 can be used to prevent the NPN transistor Q2 from being triggered and turned on by the first path module without input.
[0044] When a positive voltage is connected, that is, the input voltage is positive, the current flows out from the first input terminal. At this time, the NPN transistor Q2 meets the conduction condition, and the NPN transistor Q2 is turned on. After it is turned on, the other input circuit of the optocoupler output module is also turned on, that is, the current can pass through the first input terminal, the first resistor, the second diode D2, the voltage-stabilizing diode D3, the NPN transistor Q2, the second resistor and the second input terminal to form a conduction circuit, and the output end of the optocoupler output module can also be grounded through the sixth resistor R6 and the NPN transistor Q2, so that the input circuit is turned on. Since the NPN transistor Q2 has a current amplification effect, the trigger circuit current can be as low as uA (microampere) level and can still normally trigger the input circuit of the optocoupler output module to turn on, so as to achieve normal output of the signal.
[0045] Therefore, through the second path module, the binary input adaptive circuit can still respond to the triggering of the binary input when the voltage is small and the loop current is small, thereby making the input loop of the optocoupler output module conductive, thereby realizing the normal output of the signal, and can also adapt to the access of the active binary input, which helps to expand the scope of use of the circuit.
[0046] For wide voltage input, the open-input adaptive circuit provided in the embodiment of the present application can adapt to AC and DC voltages of 24V to 250V, that is, when the input voltage connected to the first input terminal and the second input terminal is greater than or equal to 24V and less than or equal to 250V, the selection of the first resistor and the second resistor needs to avoid large power consumption.
[0047] Optionally, in one embodiment, the first resistor and the second resistor are used as current limiting resistors of the circuit, and the resistors are selected to be resistors of the kilo-ohm level, that is, the first resistor and the second resistor are both resistors of the kilo-ohm level. 2 / R, even if the input voltage reaches 250V, the resistance power corresponding to the first resistor and the resistance power corresponding to the second resistor are small and can meet the requirements of low power consumption. When the input voltage reaches 24V, according to the resistance current I=U / R, even if the voltage drop on each device in the loop is subtracted, the current passing through the first resistor and the second resistor can still reach the microampere level, which can meet the requirements of normal signal output.
[0048] Therefore, the power consumption in the first resistor and the second resistor is relatively small, which can effectively avoid the situation where the resistors heat up severely under the condition of wide voltage active input and affect the stable operation of the circuit, and help to extend the working time of the circuit and maintain the stability of the circuit.
[0049] In one embodiment, the first resistor and the second resistor are both kilo-ohm resistors, and the sum of the resistance values of the first resistor and the second resistor is greater than or equal to 150KΩ and less than or equal to 1.5MΩ. Optionally, in one embodiment, the first resistor and the second resistor are resistors of the same resistance value, such as selecting a 150KΩ resistor, so that the input power of the optical coupling output module in the circuit is small, while the loop current can still meet the requirements of normal signal output. It should be noted that the first resistor and the second resistor are also selected as 100KΩ and 200KΩ resistors respectively. When the above conditions are met, the specific resistance value selection can be determined according to the actual application scenario of the circuit.
[0050] For example, Figure 5A schematic diagram of the circuit structure of a binary input adaptive circuit provided in one embodiment of the present application, in one embodiment, the first input terminal DIN_P of the circuit is connected to the first resistor R1, the second input terminal DIN_N is connected to the second resistor R2, and the second resistor R2 is also grounded. In addition, the first resistor R1 is also connected to the cathode end of the first diode D1, the anode end of the first diode D1 is connected to the base end of the PNP transistor Q1, the base end of the PNP transistor Q1 is connected to the emitter end of the PNP transistor Q1 through the fourth resistor R4, the collector end of the PNP transistor Q1 is connected to the first end of the fifth resistor R5, and the second end of the fifth resistor R5 is grounded.
[0051] In addition, the first resistor R1 is also connected to the anode end of the second diode D2, the cathode end of the second diode D2 is connected to the cathode end of the Zener diode D3, the anode end of the Zener diode D3 is connected to the base end of the NPN transistor Q2, the base end of the NPN transistor Q2 is also connected to the emitter end of the NPN transistor Q2 through the seventh resistor R7, the emitter end of the NPN transistor Q2 is grounded, and the collector end of the NPN transistor Q2 is connected to the first end of the sixth resistor R6.
[0052] The second end of the sixth resistor R6 and the emitter end of the PNP transistor Q1 are both connected to the emitter cathode end of the photoelectric coupler U1, the emitter anode end of the photoelectric coupler U1 is connected to the working voltage (+12V), the receiving collector end of the photoelectric coupler U1 is connected to the external voltage, the receiving emitter end of the photoelectric coupler U1 is connected to the output terminal DOUT, the receiving emitter end of the photoelectric coupler U1 is also connected to the grounded third resistor R3, and the first capacitor C1 is connected in parallel to the third resistor R3.
[0053] The operating voltage is provided by the DCDC converter U2. The input end of the DCDC converter U2 is connected to an external power supply, the input end of the DCDC converter U2 is connected to a grounded second capacitor C2, the output end of the DCDC converter U2 is connected to a grounded third capacitor C3, and the output end of the DCDC converter U2 outputs the operating voltage.
[0054] It can be understood that the PNP transistor Q1 and the NPN transistor Q2 are used as the conduction switches of the corresponding input loops in the circuit, and the corresponding loop is triggered to conduct when one of the transistors is turned on. For example, for active AC and DC inputs, when the input voltage is positive, the NPN transistor Q2 is turned on, and the current passes through the first input terminal DIN_P, the first resistor R1, the second diode D2, the voltage-stabilizing diode D3, the NPN transistor Q2, the second resistor R2 and the second input terminal DIN_N to form a conduction loop. Accordingly, the photocoupler U1 is also turned on, so as to output to the subsequent circuit through the output terminal DOUT. When the input voltage is negative, the PNP transistor Q1 is turned on, and the current passes through the PNP transistor Q1, the first diode D1, the first resistor R1, the first input terminal DIN_P, the second input terminal DIN_N, and the second resistor R2 and then flows into the ground terminal to form a conduction loop. Accordingly, the photocoupler U1 is also turned on, so as to output to the subsequent circuit through the output terminal DOUT. In this regard, no matter whether the input voltage is positive or negative, there is always a transistor that is triggered to conduct, and the circuit can achieve compatibility with AC active input.
[0055] For passive input, the first input terminal DIN_P and the second input terminal DIN_N are short-circuited, the PNP transistor Q1 is turned on, and the current flows into the ground terminal after passing through the PNP transistor Q1, the first diode D1, the first resistor R1, the first input terminal DIN_P, the second input terminal DIN_N, and the second resistor R2 to form a conduction loop. Correspondingly, the optocoupler U1 is also turned on, thereby outputting to the subsequent circuit through the output terminal DOUT.
[0056] Therefore, whether it is active input or passive input, the circuit is compatible with and can realize the transmission of input signals, and except for the first resistor R1, the second resistor R2, the first diode D1 and the second diode D2, other devices in the input loop are within the 12V low voltage level range, and the devices are all working within the safe voltage range. In addition, the first resistor and the second resistor are not easy to be damaged by heat under wide voltage input, and their resistance power is low, which can effectively reduce the power consumption of the circuit.
[0057] An embodiment of the present application also provides a circuit board, which includes the above-mentioned open-input adaptive circuit. The circuit board has the beneficial effects of the open-input adaptive circuit and realizes an open-in circuit solution that is compatible with multiple open-output types.
[0058] An embodiment of the present application also provides a relay protection tester, which includes the above-mentioned circuit board. The device is compatible with active and passive circuits, so that the device's binary input interface can be more convenient to operate and use, and the device's resistance is not easily damaged by heat under a wide voltage input, which helps to reduce the device's power consumption and extend the device's service life.
[0059] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.
[0060] Note that the above are only preferred embodiments of the present application and the technical principles used. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present application. Therefore, although the present application is described in more detail through the above embodiments, the present application is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.
Claims
1. A binary input adaptive circuit, characterized in that: include: A first resistor, one end of which is connected to a first input terminal, and the first input terminal is used to access an active binary input or a passive binary input; a second resistor, one end of the second resistor being connected to the second input terminal, the other end of the second resistor being grounded, and the second input terminal being used to access an active binary input or a passive binary input; An optocoupler output module, wherein the first output end of the optocoupler output module is connected to the output terminal, and the optocoupler output module is used to feed back to the subsequent circuit a binary input signal indicating that an active binary input quantity or a passive binary input quantity is currently connected when the second output end of the optocoupler output module is connected to a conduction voltage; A first path module, wherein a first output end of the first path module is connected to the other end of the first resistor, a second output end of the first path module is connected to the other end of the second resistor, an input end of the first path module is connected to the second output end of the optical coupling output module, and the first path module is turned on when the first input terminal is connected to a negative active binary input and the second input terminal is connected to a positive active binary input or when the first input terminal and the second input terminal are connected to a passive binary input; A second path module, wherein the first input end of the second path module is connected to the other end of the first resistor, the second input end of the second path module is connected to the second output end of the optocoupler output module, and the output end of the second path module is connected to the other end of the second resistor. When the first input terminal is connected to a positive active open input and the second input terminal is connected to a negative active open input, the second path module is turned on.
2. The binary input adaptive circuit according to claim 1, characterized in that: The optical coupling output module includes a photoelectric coupler, a third resistor and a first capacitor; The transmitting anode terminal of the photoelectric coupler is connected to the working voltage, the transmitting cathode terminal of the photoelectric coupler serves as the second output terminal of the photoelectric coupler output module, the receiving collector terminal of the photoelectric coupler is connected to the external voltage, the receiving emitter terminal of the photoelectric coupler is connected to the grounded third resistor, the first capacitor is connected in parallel to the third resistor, and the receiving emitter terminal of the photoelectric coupler serves as the first output terminal of the photoelectric coupler output module and is connected to the output terminal.
3. The binary input adaptive circuit according to claim 2, characterized in that: The optical coupling output module further includes a power isolation unit, and the power isolation unit includes a DCDC converter, a second capacitor and a third capacitor; The input end of the DCDC converter is connected to an external power supply, and the input end of the DCDC converter is connected to the grounded second capacitor. The output end of the DCDC converter is used to provide an operating voltage for the circuit, and the output end of the DCDC converter is connected to the grounded third capacitor.
4. The binary input adaptive circuit according to claim 1, characterized in that: The first path module includes a fourth resistor, a fifth resistor, a first diode and a PNP transistor; The emitter terminal of the PNP transistor serves as the output terminal of the first path module, the base terminal of the PNP transistor is connected to the emitter terminal of the PNP transistor through the fourth resistor, the base terminal of the PNP transistor is also connected to the anode terminal of the first diode, the cathode terminal of the first diode serves as the first output terminal of the first path module, the collector terminal of the PNP transistor is connected to the first end of the fifth resistor, and the second end of the fifth resistor serves as the second output terminal of the first path module.
5. The binary input adaptive circuit according to claim 1, characterized in that: The second path module includes a sixth resistor, a seventh resistor, a second diode, a voltage stabilizing diode and an NPN transistor; The collector end of the NPN transistor is connected to the first end of the sixth resistor, and the second end of the sixth resistor serves as the second input end of the second path module; The base terminal of the NPN transistor is connected to the anode terminal of the voltage-stabilizing diode, the cathode terminal of the voltage-stabilizing diode is connected to the cathode terminal of the second diode, and the anode terminal of the second diode serves as the first input terminal of the second path module; The base terminal of the NPN transistor is also connected to the emitter terminal of the NPN transistor through the seventh resistor, and the emitter terminal of the NPN transistor is grounded.
6. The binary input adaptive circuit according to claim 1, characterized in that: When the input voltage connected to the first input terminal and the second input terminal is greater than or equal to 24V and less than or equal to 250V, the first resistor and the second resistor are both resistors in the kilo-ohm range.
7. The binary input adaptive circuit according to claim 6, characterized in that: The sum of the resistance values of the first resistor and the second resistor is greater than or equal to 150KΩ and less than or equal to 1.5MΩ.
8. A circuit board, characterized in that: The invention comprises a binary input adaptive circuit as claimed in any one of claims 1 to 7.
9. A relay protection tester, characterized in that: Comprising a circuit board as claimed in claim 8.