CN211979167U - High-efficient cable open circuit detection circuitry of rectifying certainly - Google Patents
High-efficient cable open circuit detection circuitry of rectifying certainly Download PDFInfo
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- CN211979167U CN211979167U CN202020233905.4U CN202020233905U CN211979167U CN 211979167 U CN211979167 U CN 211979167U CN 202020233905 U CN202020233905 U CN 202020233905U CN 211979167 U CN211979167 U CN 211979167U
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Abstract
The utility model discloses a high-efficiency self-correcting cable open circuit detection circuit in the field of cable fault detection, which comprises an excitation power supply, and an inverse phase cut-off circuit, a voltage division circuit, a clamping circuit and a double-voltage comparison circuit which are connected with the excitation power supply; the reverse-phase cut-off circuit is connected with a resistor in series and then leads out a first detection point, a second detection point and a voltage sampling point are led out from the voltage division circuit, the first detection point and the second detection point are connected to the cable side, the voltage sampling point of the voltage division circuit outputs a voltage sampling value according to the detection results of the first detection point and the second detection point, and the clamping circuit selects whether to clamp the sampling voltage according to the detection results. The utility model provides a circuit can extensively adapt to present different voltage levels, and multiple failure mode's application possesses the ability of disturbing each other that resists different levels, different voltage networks. When a fault occurs, the fault is timely taken as an action, and the requirements of personal and equipment on safe use are met.
Description
Technical Field
The utility model relates to a cable fault detection field specifically is a high-efficient cable open circuit detection circuitry of rectifying certainly.
Background
The situation that the cable is open-circuited (disconnected) and electrically disconnected can occur in the cable application process, and the situation that the cable is open-circuited is often found when the expected signal input, output and feedback do not occur and the problem is passively searched. At present, a feedback signal is reserved for judgment, only simple disconnection detection can be carried out, and signal processing is simple.
However, the above detection and judgment are not professional enough, and when the cable is open and the connection is missed, the fault point cannot be judged and positioned in the first time, and especially when the interface is exposed, unexpected faults such as short circuit may occur. And a simple path of feedback signal is adopted as cable open circuit detection judgment, so that the defect of no self-error correction exists, and meanwhile, the application occasions are more limited by the voltage network grade and the open circuit type, so that greater potential safety hazards exist.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a high-efficient cable open circuit detection circuitry of rectifying to solve the problem that proposes among the above-mentioned background art.
In order to achieve the above object, the utility model provides a following technical scheme:
a high-efficiency self-error-correction cable open circuit detection circuit comprises an excitation power supply, and an inverted cut-off circuit, a voltage division circuit, a clamping circuit and a double-voltage comparison circuit which are connected with the excitation power supply; the reverse-phase cut-off circuit is connected with a resistor in series and then leads out a first detection point, a second detection point and a voltage sampling point are led out from the voltage dividing circuit, the first detection point and the second detection point are connected to the cable side, the voltage sampling point of the voltage dividing circuit outputs a voltage sampling value according to the detection results of the first detection point and the second detection point, and the clamping circuit selects whether to clamp the sampling voltage according to the detection result; the sampling voltage is output to a double-voltage comparison circuit, the double-voltage comparison circuit outputs a comparison level to a fault reporting isolation circuit according to a voltage sampling value, and the fault reporting isolation circuit changes the on-off state of the fault reporting isolation circuit according to the comparison level value and triggers and uploads the fault state.
As the utility model discloses an improvement scheme, when first check point and second check point detection cable do not have the trouble, the excitation power process reverse phase is imported behind the end circuit bleeder circuit, bleeder circuit output sample voltage extremely two voltage comparison circuit, two voltage comparison circuit output high level extremely fault report isolating circuit, fault report isolating circuit ends.
As the utility model discloses an improvement scheme, the cable between first check point and the second check point is opened a way, perhaps, when first check point detects the cable short circuit and the cable between first check point and the second check point is opened a way, bleeder circuit output sampling voltage is zero to be connected to two voltage comparison circuit, two voltage comparison circuit output low level extremely fault report isolating circuit, fault report isolating circuit switches on to trigger and upload cable fault state.
As the utility model discloses an improvement scheme, first check point detection cable short circuit, perhaps, when the second check point detects the cable short circuit and the cable between first check point and the second check point is opened circuit, the cable voltage flows in bleeder circuit through the second check point, clamping circuit does bleeder circuit's sampling voltage clamper, then output sample voltage after the clamper extremely two voltage comparison circuit, two voltage comparison circuit output low level extremely the fault reports isolating circuit, the fault reports isolating circuit switches on to the cable fault condition is uploaded in the triggering.
Has the advantages that: the utility model provides a circuit can extensively adapt to present different voltage levels, and multiple failure mode's application possesses the ability of disturbing each other that resists different levels, different voltage networks. When a fault occurs, the fault is timely taken as an action, and the requirements of personal and equipment on safe use are met.
Drawings
Fig. 1 is a circuit block diagram of the present invention;
FIG. 2 is a schematic circuit diagram of the present invention;
fig. 3 is a truth table of point D of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In this embodiment, +5V1 and GND1 are a set of excitation power supply, the reverse cut-off circuit includes a diode V1 and a diode V2 connected in series in the forward direction, the anode terminal of the diode V1 is connected to +5V1, the cathode terminal of the diode V2 is connected to the first terminal of a resistor R1, and the second terminal of the resistor R1 is used as a first detection point, specifically, point a in fig. 2. The first end of the resistor R1 is connected with a capacitor C1, the second end thereof is connected with a capacitor C2, and the ends of the capacitor C1 and the capacitor C2 are connected with GND 1.
In this embodiment, the second detection point (point B in the figure) is connected to the first end of the resistor R2, the second end of the resistor R2 is connected in series with the resistor R3, the resistor R4, the resistor R5, the resistor R6, the resistor R7, and the resistor R9, a common end of the resistor R9 and the resistor R7 serves as a voltage sampling point (point C), the resistor R8 and the capacitor C6 are connected, and end portions of the resistor R8 and the capacitor C6 are both connected to the GND 1.
The capacitor C5 is connected to the common end of the resistor R5 and the resistor R6, the capacitor C3 and the capacitor C4 are further connected to the point B, and the ends of the capacitor C3, the capacitor C4 and the capacitor C5 are connected with the GND 1.
In this embodiment, the clamping circuit includes a zener diode V3 and a diode V4, a cathode terminal of the zener diode V3 is connected to a common terminal of the resistor R9 and the resistor R7, and an anode terminal thereof is connected to the GND 1; the cathode terminal of the diode V4 is connected to +5V1, and the anode terminal is connected to the end of the resistor R9.
In this embodiment, the voltage comparison circuit includes a voltage comparator N1A and a voltage comparator N1B, and further includes a resistor R10, a resistor R11 and a resistor R12, wherein the non-inverting terminal (pin 3) of the voltage comparator N1A and the inverting terminal (pin 6) of the voltage comparator N1B are commonly connected to the common terminal of the diode V4 and the resistor R9. A first end of the resistor R10 is connected to +5V1, a second end of the resistor R10 is connected to a first end of the resistor R11 and a non-inverting end (pin 5) of the voltage comparator N1B, a second end of the resistor R11 is connected to a first end of the resistor R12 and an inverting end (pin 2) of the voltage comparator N1A, a second end of the resistor R12 and a ground end (pin 4) of the voltage comparator N1A are both connected to GMD1, and a power supply terminal (pin 8) of the voltage comparator N1A is connected to +5V 1.
The two ends of the resistor R11 and the resistor R12 are respectively connected with the capacitor C7 and the capacitor C8 in parallel, the power supply end of the voltage comparator N1A is also connected with the capacitor C9, and the end of the capacitor C9 is connected with the GND 1.
In this embodiment, the fault reporting isolation circuit includes an optocoupler U1 (model is TLP 291), a 2-pin of the optocoupler U1 is connected to an output terminal (1-pin) of the voltage comparator N1A and an output terminal (7-pin) of the voltage comparator N1B, a common output terminal of the voltage comparator N1A and the voltage comparator N1B serves as a point D, an output terminal of the voltage comparator N1B is further connected to a capacitor C10, and an end of the capacitor C10 is grounded. The 1 pin of the optocoupler U1 is connected with a resistor R13 in series and then connected to +5V1, the 4 pin thereof is led out from the point E, and is connected with a resistor R14 in series and then connected with a +5.0V power supply, and the 3 pin thereof is connected with GND.
Through the injection of excitation power supply, the utility model discloses carry out signal processing, whether open a way the trouble appears in the accurate judgement cable. Meanwhile, if direct-current high voltage is led into the detection circuit through the broken skin and the broken wire, the cable open-circuit detection circuit can also make fault judgment immediately.
Further, in this embodiment, when the point a and the point B detect that the cable has no fault, the excitation power passes through the reverse-phase cut-off circuit and is input to the voltage dividing circuit, the voltage dividing circuit outputs the sampling voltage to the dual-voltage comparing circuit, the dual-voltage comparing circuit outputs the high level to the fault reporting isolation circuit, and the fault reporting isolation circuit is cut off.
Specifically, in normal application, the point a and the point B are connected together by an external cable, and the excitation power supply +5V1 is injected into the voltage dividing circuit from the diode V1 and the diode V2 in the reverse blocking circuit, and after voltage division is performed by the resistors R1 to R8, voltage sampling is performed at the point C. The voltage sampling values are respectively sent to the 3 pin of the voltage comparator N1A and the 6 pin of the voltage comparator N1B, the 2 pin of the voltage comparator N1A and the 5 pin of the voltage comparator N1B are inputted with reference voltage signals, and the reference voltage signals are introduced by the voltage division values of the resistors R10-R12. At this time, the input voltage of the 5 pin of the voltage comparator N1B is greater than the input voltage of the 6 pin, which outputs a high level; since the voltage value of the 3 pin of the voltage comparator N1A is equal to the voltage value of the 6 pin of the voltage comparator N1B and is greater than the voltage value of the 2 pin thereof, the voltage comparator N1A outputs a high level, and the point D is a high level. The optocoupler U1 is not painful, point E remains in the high level state, and the cable fault state is not reported, which corresponds to column number 4 in fig. 3.
Because the input impedance of the voltage division circuit is large, under a complex electromagnetic environment, strong interference can be connected in a loop in series, and even circuit misoperation can be caused. The capacitor needs to be added at a proper position, and the C1-C6 are filter capacitors, so that the interference signals can be effectively inhibited or filtered, and the stable and reliable work of the circuit is realized. By adjusting the resistance values of the resistors R10-R12, the voltage difference between the pins 2 and 3 of the voltage comparator N1A and between the pins 5 and 6 of the voltage comparator N1B can be about 1V, and the fault tolerance is reasonable. Capacitors C7-C10 are near-end filter capacitors of each point.
Further, in this embodiment, when the cable between the point a and the point B is open-circuited, or the point a detects that the cable is short-circuited and the cable between the point a and the point B is open-circuited, the voltage dividing circuit outputs a sampling voltage of zero and is connected to the dual-voltage comparing circuit, the dual-voltage comparing circuit outputs a low level to the fault reporting isolation circuit, and the fault reporting isolation circuit is turned on and triggers a fault state of the uploading cable.
Specifically, when only an open circuit is formed between the point a and the point B, the point B has no excitation power supply, the sampling voltage at the point C is zero, the reference voltage of the 2 pin of the voltage comparator N1A is greater than the sampling voltage, the 1 pin outputs a low level, the reference voltage of the 5 pin of the N1B is greater than the sampling voltage value, the 7 pin outputs a high level, finally the point D is a low level, the optocoupler U1 is turned on, and the point E is turned from the high level to the low level to trigger the fault state of the upload cable, which corresponds to the column number 2 in fig. 3.
Specifically, when the circuit is opened between the point a and the point B, and the cable is detected to be broken at the point a, the point a is connected in series with the cable direct-current high voltage, and due to the inverted connection of the diode V1 and the diode V2 in the inverted cut-off circuit relative to the point a, the direct-current high voltage cannot enter the +5V1 excitation power supply and the front-end circuit through the diode V1 and the diode V2, so that the protection of the front-end circuit is realized. And because an open circuit is formed between the point A and the point B, the point B has no excitation power supply, the sampling voltage at the point C is zero, the reference voltage of the 2 pin of the voltage comparator N1A is greater than the sampling voltage, the 1 pin outputs a low level, the reference voltage of the 5 pin of the N1B is greater than the sampling voltage value, the 7 pin outputs a high level, finally the point D is a low level, the optocoupler U1 is conducted, the point E is inverted from the high level to the low level, and the fault state of the uploading cable is triggered, which corresponds to the column number 2 in the figure 3.
Further, in this embodiment, when the point a detects a short circuit of the cable, or the point B detects a short circuit of the cable and the cable between the point a and the point B is open, the voltage of the cable flows into the voltage dividing circuit through the point B, the clamping circuit clamps the sampling voltage of the voltage dividing circuit, and then outputs the clamped sampling voltage to the dual-voltage comparing circuit, the dual-voltage comparing circuit outputs a low level to the fault reporting isolating circuit, the fault reporting isolating circuit is turned on, and the fault state of the cable is triggered and uploaded.
Specifically, when the cable is detected to be broken at the point A and no fault exists between the point A and the point B, the point A penetrates into the direct-current high voltage, and the point A and the point B are the same point. Because the diode V1 and the diode V2 in the inverting cutoff circuit are connected in an inverted manner relative to the point A, direct-current high voltage cannot enter the +5V1 excitation power supply and the front-end circuit through the diode V1 and the diode V2, and the front-end circuit is protected. At the moment, the direct-current high voltage flows into a voltage dividing circuit on the rear stage side through a point B, and due to the current limiting and voltage dividing of resistors R2-R8, the sampling voltage on the point C is clamped by a voltage stabilizing diode V3 and then is clamped by a diode V4 for two stages, so that the rear stage voltage of R9 is less than or equal to 5V. At this time, the reference voltage of the 2 pin of the voltage comparator N1A is smaller than the sampling voltage, the 1 pin outputs a high level, the reference voltage of the 5 pin of N1B is smaller than the sampling voltage value, the 7 pin outputs a low level, finally, the point D is a low level, the optocoupler U1 is turned on, the point E is turned over from the high level to the low level, and the fault state of the upload cable is triggered, which corresponds to the column 3 in fig. 3.
Preferably, the post-stage voltage of the resistor R9 is preferably 5V according to the types of the current-limiting voltage-dividing resistors R2-R8 and the voltage-stabilizing diode V3.
Specifically, when a cable is broken at a point B and the cable between the point A and the point B is open-circuited, a direct-current high voltage is connected to the point B in series, an excitation power supply is injected into an inverting cut-off circuit and then forms an open circuit at the point A, the direct-current high voltage flows into a post-stage circuit through the point B, and due to the current limiting and voltage dividing of resistors R2-R8, the sampling voltage at the point C is clamped by a voltage stabilizing diode V3 and then is clamped by a diode V4 for the second-stage clamping, so that the post-stage voltage of R9 is 5V. At this time, the reference voltage of the 2 pin of the voltage comparator N1A is smaller than the sampling voltage, the 1 pin outputs a high level, the reference voltage of the 5 pin of N1B is smaller than the sampling voltage value, the 7 pin outputs a low level, finally, the point D is a low level, the optocoupler U1 is turned on, the point E is inverted from the high level to the low level, and the fault state of the upload cable is triggered, which corresponds to the column 3 in fig. 3, and the situation in the column number 1 in fig. 3 does not occur in this embodiment.
The utility model is suitable for the application occasions of DC 0V-DC 1100V bus voltage, realizes the cable open circuit detection, and can also be safely detected if the cable breaks the skin or the external stress causes the cable to break, causing the direct current high voltage to be mixed in, and reporting the fault; the multifunctional connector has the advantages that the multifunctional connector covers 4 working modes, can perform two-stage comparison output, has a mutual error correction function, is reliable in fault judgment, meets the practical application of many occasions such as missed connection of connectors, introduction of voltages of different levels due to external force loosening, disconnection and skin breaking, and timely acts as an action when a fault occurs, and meets the requirements of personal and equipment safe use.
Although the present description is described in terms of embodiments, not every embodiment includes only a single embodiment, and such description is for clarity only, and those skilled in the art should be able to integrate the description as a whole, and the embodiments can be appropriately combined to form other embodiments as will be understood by those skilled in the art.
In the description of the present invention, it is noted that relational terms such as first and second, and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
In the description of the present invention, it should be further noted that the terms "upper", "lower", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the products of the present invention are used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Therefore, the above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application; all changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims (4)
1. A high-efficiency self-error-correction cable open circuit detection circuit is characterized by comprising an excitation power supply, and an inverted cut-off circuit, a voltage division circuit, a clamping circuit and a double-voltage comparison circuit which are connected with the excitation power supply; the reverse-phase cut-off circuit is connected with a resistor in series and then leads out a first detection point, a second detection point and a voltage sampling point are led out from the voltage dividing circuit, the first detection point and the second detection point are connected to the cable side, the voltage sampling point of the voltage dividing circuit outputs a voltage sampling value according to the detection results of the first detection point and the second detection point, and the clamping circuit selects whether to clamp the sampling voltage according to the detection result; the sampling voltage is output to a double-voltage comparison circuit, the double-voltage comparison circuit outputs a comparison level to a fault reporting isolation circuit according to a voltage sampling value, and the fault reporting isolation circuit changes the on-off state of the fault reporting isolation circuit according to the comparison level value and triggers and uploads the fault state.
2. The high-efficiency self-error-correcting cable open circuit detection circuit according to claim 1, wherein when the first detection point and the second detection point detect that the cable has no fault, an excitation power source passes through the reverse cut-off circuit and then is input to the voltage division circuit, the voltage division circuit outputs a sampling voltage to the dual-voltage comparison circuit, the dual-voltage comparison circuit outputs a high level to the fault reporting isolation circuit, and the fault reporting isolation circuit is cut off.
3. The efficient self-error-correcting cable open circuit detection circuit according to claim 1, wherein the cable between the first detection point and the second detection point is open, or when the first detection point detects a cable short circuit and the cable between the first detection point and the second detection point is open, the voltage divider circuit outputs a sampling voltage of zero and is connected to a dual-voltage comparison circuit, the dual-voltage comparison circuit outputs a low level to the fault reporting isolation circuit, and the fault reporting isolation circuit is turned on and triggers a fault state of the uploading cable.
4. The efficient self-error-correcting cable open circuit detection circuit according to claim 1, wherein the first detection point detects a cable short circuit, or when the second detection point detects a cable short circuit and a cable between the first detection point and the second detection point is open circuit, a cable voltage flows into the voltage divider circuit through the second detection point, the clamping circuit clamps a sampling voltage of the voltage divider circuit and then outputs the clamped sampling voltage to the dual-voltage comparison circuit, the dual-voltage comparison circuit outputs a low level to the fault reporting isolation circuit, and the fault reporting isolation circuit is turned on and triggers a fault state of the uploading cable.
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| CN202020233905.4U CN211979167U (en) | 2020-02-28 | 2020-02-28 | High-efficient cable open circuit detection circuitry of rectifying certainly |
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| CN202020233905.4U CN211979167U (en) | 2020-02-28 | 2020-02-28 | High-efficient cable open circuit detection circuitry of rectifying certainly |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114019432A (en) * | 2021-11-04 | 2022-02-08 | 上海自动化仪表有限公司 | Method and system for acquiring magnetic resistance type rotating speed signal with open circuit detection |
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2020
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114019432A (en) * | 2021-11-04 | 2022-02-08 | 上海自动化仪表有限公司 | Method and system for acquiring magnetic resistance type rotating speed signal with open circuit detection |
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