Surge protector

Abstract

The utility model discloses a surge protector which comprises a lightning protection circuit, a first monitoring circuit and a second monitoring circuit. The surge protector is connected with the first monitoring circuit and the second monitoring circuit, and the first monitoring circuit is connected with the state indicating lamp in the surge protector, so that whether the state indicating lamp has a fault or not can be monitored. And the second monitoring circuit is connected with the power supply protection circuit in the surge protector, so that whether the power supply protection circuit of the state indicating lamp fails or not can be monitored. On the basis, the condition that the state indicating lamp is extinguished and misinformation is caused due to faults of the state indicating lamp or the power supply protection circuit can be avoided, so that the accuracy of indicating the working state of the surge protector by the state indicating lamp is improved, and the technical effect of saving the use cost is achieved. Meanwhile, efficient communication with after-sales maintenance personnel can be improved, and the technical effect of improving the maintenance accuracy of the surge protector is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of power supply, and particularly relates to a surge protector. Background Art

[0002] A surge protector is an electronic device that provides safety protection for various electronic devices, instruments, and communication lines. When a sharp peak current or voltage suddenly occurs in an electrical circuit or communication line due to external interference, the surge protector can conduct and shunt in an extremely short time to avoid damage to other devices in the circuit caused by the surge. However, the lifespan of the varistor that plays a protective role in the surge protector decreases as the number of lightning pulses processed increases. When the invading lightning pulses exceed the processing capacity of the varistor, it is easy to cause the surge protector to trip and disconnect, resulting in the failure of the surge protector.

[0003] In the existing surge protectors, a status indicator is set to display whether the surge protector fails. When the status indicator is in a constantly lit state, it proves that the surge protector is in a normal working state. When the status indicator is in an extinguished state, it proves that the surge protector is in a failed state. However, in the actual use process, the status indicator in the surge protector will cause false alarms in the following scenarios, resulting in after-sales processing of the surge protector that has not actually failed, affecting production efficiency and the progress of production tasks, and increasing the use cost of the surge protector. Among them, the scenarios that cause false alarms of the status indicator are specifically as follows:

[0004] (1) The status indicator is extinguished due to some reason or its own quality problem;

[0005] (2) The status indicator is extinguished due to a power supply circuit failure;

[0006] (3) When the connection cable of the status indicator is subjected to a certain stress during installation, causing the cable to break or the plug to become loose, resulting in the extinguishment of the status indicator;

[0007] At the same time, after the status indicator is extinguished, the surge protector is usually directly replaced or subjected to after-sales processing, further increasing the use cost. Summary of the Utility Model

[0008] In view of the above problems, the utility model discloses a surge protector to overcome or at least partially solve the above problems.

[0009] To achieve the above object, the utility model adopts the following technical solutions:

[0010] A surge protector includes a lightning protection circuit, a first monitoring circuit, and a second monitoring circuit;

[0011] The lightning protection circuit comprises a power supply protection circuit and a status indicator light which are sequentially connected between the positive power supply electrode and the negative power supply electrode; the status indicator light is used to indicate whether the lightning protection circuit fails;

[0012] The first monitoring circuit is connected to the status indicator light and is used to monitor whether the status indicator light fails; the second monitoring circuit is connected to the power supply protection circuit and is used to monitor whether the power supply protection circuit fails.

[0013] Further, the first monitoring circuit includes a differential circuit and a display circuit;

[0014] The two input ends of the differential circuit are respectively connected to the positive and negative poles of the status indicator light, and the output end of the differential circuit is connected to the display circuit for calculating the difference between the amplified positive voltage of the status indicator light and the negative voltage of the status indicator light. The display circuit is used to indicate whether the status indicator light is faulty.

[0015] Further, the display circuit includes a third triode, a fourth triode, a twelfth resistor, an eighth resistor, a two-color diode and a ninth resistor;

[0016] The base of the third transistor and the base of the fourth transistor are both connected to the differential circuit through the twelfth resistor;

[0017] The emitter of the third triode is connected to the positive power supply electrode through the eighth resistor, and the collector of the third triode is connected to the first end of the two-color diode;

[0018] The emitter of the fourth triode is connected to the second end of the two-color diode, and the common end of the two-color diode is connected to the negative power supply electrode; the collector of the fourth triode, the ninth resistor and the positive power supply electrode are connected in sequence.

[0019] Further, the second monitoring circuit includes a fourth capacitor, a nineteenth resistor and a fifth diode;

[0020] The anodes of the fourth capacitor, the nineteenth resistor and the fifth diode are connected in sequence, the cathode of the fifth diode is connected to the negative power supply electrode, the fourth capacitor is connected to the power supply protection circuit, and the fifth diode is a light emitting diode.

[0021] Further, it also includes a fault indication circuit;

[0022] The lightning protection circuit also includes a second photoelectric coupler; the fourth end of the second photoelectric coupler is connected to the negative electrode of the status indicator light, the first end of the second photoelectric coupler is connected to the power supply protection circuit; the third end of the second photoelectric coupler is connected to the negative electrode of the power supply;

[0023] The fault indication circuit is connected to the second end of the second optocoupler and is used to detect the on / off state of the power supply protection circuit.

[0024] Further, the fault indication circuit includes a relay, a first triode, a second resistor, a self-check switch, a first resistor, a second triode, a second diode, a first diode, a third resistor, and a sixth resistor;

[0025] The first contact of the relay is connected to the second end of the second optocoupler; the second contact of the relay is connected to the collector of the first triode, the emitter of the first triode is connected to the negative power supply, the base of the first triode is respectively connected to one end of the second resistor and one end of the first resistor, and the other end of the second resistor is connected to the positive power supply through the self-check switch; the other end of the first resistor is connected to the base of the second triode;

[0026] The emitter of the second triode, the second diode, and the negative pole of the status indicator light are connected in sequence, the collector of the second triode, the first diode, the third resistor, and the positive power supply are connected in sequence, and the first diode is a light-emitting diode;

[0027] The sixth contact of the relay, the sixth resistor, and the positive power supply are connected in sequence;

[0028] The first contact of the relay or the fourteenth contact of the relay can be connected to the seventh contact of the relay;

[0029] The seventh contact of the relay is connected to the zero line;

[0030] When the self-check switch is in the normally open state, the first contact of the relay is conducted with the seventh contact of the relay; when the self-check switch is in the closed state, the fourteenth contact of the relay is conducted with the seventh contact of the relay.

[0031] Further, the fault indication circuit further includes a third optocoupler, a twenty-ninth resistor, a sixth triode, a thirtieth resistor, and a redundant display element;

[0032] The seventh contact of the relay is connected to the zero line through the second end of the third optocoupler, and the first end of the third optocoupler is connected to the seventh contact of the relay; the fourth end of the third optocoupler is connected to the positive power supply;

[0033] The third terminal of the third optocoupler is respectively connected to one end of the twenty-ninth resistor and the base of the sixth triode. The other end of the twenty-ninth resistor and the emitter of the sixth triode are respectively connected to the negative power supply. The collector of the sixth triode, the thirtieth resistor, the redundant display element, and the positive power supply are connected in sequence.

[0034] Further, the redundant display element is a light-emitting element.

[0035] Further, a wire break detection circuit is further included; the wire break detection circuit is connected to the negative electrode of the status indicator lamp and is used to detect the on-off of the internal circuit of the status indicator lamp itself.

[0036] Further, the wire break detection circuit includes a fifth amplifier, a twenty-eighth resistor, a seventh diode, a twenty-sixth resistor, a twenty-seventh resistor, a twenty-fifth resistor, and a sixth capacitor;

[0037] The output terminal of the fifth amplifier, the twenty-eighth resistor, and the positive electrode of the seventh diode are connected in sequence. The negative electrode of the seventh diode is connected to the negative power supply. The seventh diode is a light-emitting diode. The negative power supply terminal of the fifth amplifier is connected to the negative power supply;

[0038] The positive input terminal of the fifth amplifier is respectively connected to one end of the twenty-sixth resistor and one end of the twenty-seventh resistor. The other end of the twenty-sixth resistor is connected to the negative power supply. The other end of the twenty-seventh resistor is connected to the positive power supply;

[0039] The negative input terminal of the fifth amplifier, the twenty-fifth resistor, and the negative electrode of the status indicator lamp are connected in sequence;

[0040] The positive power supply terminal of the fifth amplifier is respectively connected to the positive power supply and one end of the sixth capacitor. The other end of the sixth capacitor is connected to the negative power supply.

[0041] The advantages and beneficial effects of the present utility model are:

[0042] In the surge protector of the present utility model, a first monitoring circuit and a second monitoring circuit are connected to the surge protector. By connecting the first monitoring circuit to the status indicator light in the surge protector, it is possible to monitor whether the status indicator light itself is faulty. Further, by connecting the second monitoring circuit to the power supply protection circuit in the surge protector, it is possible to monitor whether the power supply protection circuit of the status indicator light is faulty. Based on this, it is possible to avoid the situation where the status indicator light is extinguished and false alarms are triggered due to a fault in the status indicator light itself or the power supply protection circuit, thereby improving the accuracy of the status indicator light indicating the working state of the surge protector, avoiding unnecessary after-sales maintenance, and further achieving the technical effect of saving usage costs. At the same time, it can also improve the efficient communication with after-sales maintenance personnel and achieve the technical effect of improving the accuracy of surge protector maintenance and repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present utility model. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0044] Figure 1 is the connection block diagram between the lightning protection circuit, the first monitoring circuit and the second monitoring circuit in the surge protector of this embodiment;

[0045] Figure 2 is the connection schematic diagram of the lightning protection circuit in the surge protector of this embodiment;

[0046] Figure 3 is the connection schematic diagram of the first port and the second port of the first monitoring circuit and the lightning protection circuit in the surge protector of this embodiment;

[0047] Figure 4 is the connection schematic diagram of the first monitoring circuit in the surge protector of this embodiment;

[0048] Figure 5 is the connection schematic diagram of the second monitoring circuit in the surge protector of this embodiment;

[0049] Figure 6 is the connection schematic diagram of the open circuit detection circuit in the surge protector of this embodiment;

[0050] Figure 7 is the connection schematic diagram of the display circuit and the lightning protection circuit in the surge protector of this embodiment.

[0051] In the figure: 1. Lightning protection circuit; 2. First monitoring circuit; 3. Second monitoring circuit;

[0052] VCC, positive power supply terminal; U2, the second optocoupler; D6, the sixth diode;

[0053] R4, the fourth resistor; R5, the fifth resistor; R11, the eleventh resistor; MOV, metal oxide varistor; RV1, fuse; check+, positive terminal of the status indicator; check-, negative terminal of the status indicator; L, live wire; N, neutral wire;

[0054] Port1, the first port; Port2, the second port;

[0055] R15, the fifteenth resistor; A2, the second amplifier; R14, the fourteenth resistor; C2, the second capacitor; R17, the seventeenth resistor; R21, the twenty - first resistor; A4, the fourth amplifier; R16, the sixteenth resistor; A3, the third amplifier; R13, the thirteenth resistor; C3, the third capacitor; R18, the eighteenth resistor; R22, the twenty - second resistor; R24, the twenty - fourth resistor; R23, the twenty - third resistor; C5, the fifth capacitor;

[0056] Q3, the third triode; Q4, the fourth triode; R12, the twelfth resistor; R8, the eighth resistor; DS1, dual - color diode; R9, the ninth resistor;

[0057] AC / DC2, AC - DC converter; C4, the fourth capacitor; R19, the nineteenth resistor; D5, the fifth diode;

[0058] A5, the fifth amplifier; R28, the twenty - eighth resistor; D7, the seventh diode; R26, the twenty - sixth resistor; R27, the twenty - seventh resistor; R25, the twenty - fifth resistor; C6, the sixth capacitor;

[0059] K1, relay; Q1, the first triode; R2, the second resistor; S1, self - test switch; R1, the first resistor; Q2, the second triode; D2, the second diode; D1, the first diode; R3, the third resistor; R6, the sixth resistor; U3, the third optocoupler; R29, the twenty - ninth resistor; Q6, the sixth triode; R30, the thirtieth resistor; D8, light - emitting diode. Detailed implementation manners

[0060] To make the objectives, technical solutions and effects of the present utility model clearer, the technical solutions of the present utility model will be clearly and completely described below in conjunction with specific embodiments of the present utility model and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts fall within the scope of protection of the present utility model.

[0061] The technical solutions provided by the embodiments of the present utility model will be described in detail below with reference to the accompanying drawings.

[0062] Combined with Figure 1 As shown, the surge protector of this embodiment includes a lightning protection circuit 1, a first monitoring circuit 2, and a second monitoring circuit 3.

[0063] Combined with Figure 2 As shown, the lightning protection circuit 1 includes a power supply positive electrode VCC, a power supply protection circuit, a status indicator light, a second optocoupler U2, and a power supply negative electrode that are connected in sequence. The power supply negative electrode is grounded, and the status indicator light is used to indicate whether the lightning protection circuit fails. Among them, the status indicator light is the sixth diode D6, and specifically, the sixth diode D6 is a light-emitting diode.

[0064] It should be noted that the power supply protection circuit includes a power supply circuit and a protection circuit. The power supply circuit and the protection circuit are connected. The power supply circuit is used to supply power to the status indicator light, and the protection circuit is used to absorb the energy of lightning pulses and give the technical effect of protecting the device.

[0065] Specifically, the power supply circuit includes an AC / DC converter AC / DC2. Combined with Figure 2 As shown, the first end of the AC / DC converter AC / DC2 ( Figure 2 the position marked 1 of the AC / DC converter in Figure 2 is connected to the power supply positive electrode VCC, and the second end of the AC / DC converter AC / DC2 ( Figure 2 the position marked 2 of the AC / DC converter in Figure 2 is connected to the power supply negative electrode. The third end of the AC / DC converter AC / DC2 (

[0066] the position marked 3 of the AC / DC converter in Figure 2 is connected to the live wire L, and the fourth end of the AC / DC converter AC / DC2 ( Figure 2 the position marked 4 of the AC / DC converter in Figure 2 is connected to the neutral wire N. Figure 2 Figure 2 Figure 2 The protection circuit includes a varistor, a fourth resistor R4, a fifth resistor R5, and an eleventh resistor R11. Specifically, combined with Figure 2is connected to the neutral line N at the position marked 2 of the second opto-coupler), and the third terminal of the second opto-coupler U2 ( Figure 2 is connected to the negative power supply at the position marked 3 of the second opto-coupler), and the fourth terminal of the second opto-coupler U2 ( Figure 2 at the position marked 4 of the second opto-coupler), the positive pole check+ of the status indicator light, the negative pole check- of the status indicator light, the eleventh resistor R11, and the positive power supply VCC are connected in sequence.

[0067] Among them, the varistor includes a series-connected metal oxide varistor MOV and a fuse RV1. The end point of the metal oxide varistor MOV grounded serves as the first terminal of the varistor, the connection point between the metal oxide varistor MOV and the fuse RV1 serves as the third terminal of the varistor, and the connection end point between the fuse RV1 and the live wire L serves as the second terminal of the varistor. When the varistor fails and overcurrents or the energy of a lightning pulse invasion exceeds the tolerance of the fuse RV1, the fuse RV1 melts, and the connection between the second terminal and the third terminal of the varistor is disconnected, so that no current flows through the second opto-coupler U2. At this time, the status indicator light is in the off state, indicating that the surge protector has failed and needs to be replaced and repaired. In this embodiment, an AC lightning protection circuit is taken as an example. Of course, the principle of the DC lightning protection circuit is the same as that of the surge protector in this embodiment.

[0068] Furthermore, in combination with Figure 1 and Figure 3 as shown, one end of the first monitoring circuit is connected to the positive pole check+ of the status indicator light, and the other end of the first monitoring circuit is connected to the negative pole check- of the status indicator light, for monitoring whether the status indicator light fails. The second monitoring circuit is connected to the protection circuit, for monitoring whether the protection circuit fails.

[0069] Based on this, when the status indicator light is off, it can be monitored through the first monitoring circuit and the second monitoring circuit to avoid the situation where the status indicator light is off due to its own failure and the circuit failure of the power supply of the status indicator light, so as to achieve the technical effect of improving the accuracy of the status indicator light indicating the working state of the surge protector. Among them, the working state of the surge protector refers to whether the surge protector fails.

[0070] In the surge protector of this embodiment, by connecting a first monitoring circuit and a second monitoring circuit to the surge protector, and using the first monitoring circuit to connect to the status indicator in the surge protector, it is possible to monitor whether the status indicator itself is faulty. Further, by connecting the second monitoring circuit to the power supply protection circuit in the surge protector, it is possible to monitor whether the power supply protection circuit of the status indicator is faulty. Based on this, it is possible to avoid the occurrence of false alarms of the status indicator caused by a fault in the status indicator itself or the power supply protection circuit, thereby improving the accuracy of the status indicator indicating the working state of the surge protector, avoiding unnecessary after-sales maintenance situations, and thus achieving the technical effect of saving usage costs. At the same time, it can also improve the efficient communication with after-sales maintenance personnel, achieving the technical effect of improving the accuracy of surge protector maintenance.

[0071] In addition, preferably, in this embodiment, in combination with Figure 3 As shown, the first monitoring circuit 2 includes a first port Port1, a second port Port2, a differential circuit, and a display circuit. The first port Port1 is connected to the positive electrode check+ of the status indicator as an input terminal of the differential circuit, and the second port Port2 is connected to the negative electrode check- of the status indicator as the other input terminal of the differential circuit, for extracting the positive electrode voltage of the status indicator and the negative electrode voltage of the status indicator. The output terminal check OUT of the differential circuit is connected to the display circuit.

[0072] Specifically, the differential circuit calculates and amplifies the difference between the positive electrode voltage and the negative electrode voltage of the status indicator after amplification, judges whether the status indicator is in a normal working state according to the difference, and outputs the judgment result to the display circuit. The staff judges whether the extinguishing of the status indicator is a false alarm through the visual signal displayed by the display circuit, so as to avoid unnecessary after-sales processing situations and thus improve work efficiency. At the same time, by using the differential circuit to output the working state of the status indicator, the anti-interference ability of the first monitoring circuit can be improved, thereby achieving the technical effect of improving the accuracy of the monitoring result of the first monitoring circuit.

[0073] In combination with Figure 4 As shown, in this embodiment, the differential circuit includes a fifteenth resistor R15, a second amplifier A2, a fourteenth resistor R14, a second capacitor C2, a seventeenth resistor R17, a twenty-first resistor R21, a fourth amplifier A4, a sixteenth resistor R16, a third amplifier A3, a thirteenth resistor R13, a third capacitor C3, an eighteenth resistor R18, a twenty-second resistor R22, a twenty-fourth resistor R24, a twenty-third resistor R23, and a fifth capacitor C5.

[0074] Among them, in combination with Figure 4As shown, the positive pole check+ of the status indicator light, the fifteenth resistor R15, and the positive input terminal of the second amplifier A2 ( Figure 4 the position marked 3 of the second amplifier in Figure 4 ) are connected in sequence. The negative power supply terminal of the second amplifier A2 ( Figure 4 the position marked 2 of the second amplifier in Figure 4 ) is connected to the negative pole of the power supply. The negative input terminal of the second amplifier A2 ( Figure 4 the position marked 4 of the second amplifier in Figure 4 ) is connected to one end of the fourteenth resistor R14, and the other end of the fourteenth resistor R14 is connected to the negative pole of the power supply. The positive power supply terminal of the second amplifier A2 ( Figure 4 the position marked 5 of the second amplifier in

[0075] ) is respectively connected to the positive power supply VCC and one end of the second capacitor C2, and the other end of the second capacitor C2 is connected to the negative pole of the power supply. The seventeenth resistor R17 is connected between the output terminal check+OUT of the second amplifier A2 ( Figure 4 the position marked 1 of the second amplifier in Figure 4 ) and the negative input terminal of the second amplifier A2. The output terminal check+OUT of the second amplifier A2 is respectively connected to the positive input terminal of the fourth amplifier A4 ( Figure 4 the position marked 3 of the fourth amplifier in Figure 4 ) and one end of the twenty-third resistor R23 through the twenty-first resistor R21. The other end of the twenty-third resistor R23 is connected to the negative pole of the power supply. The output terminal check OUT of the fourth amplifier A4 ( Figure 4 the position marked 1 of the fourth amplifier in Figure 4 ) is connected to the status display circuit.

[0075] Furthermore, the negative pole check- of the status indicator light, the sixteenth resistor R16, and the positive input terminal of the third amplifier A3 ( Figure 4 the position marked 3 of the third amplifier in Figure 4 ) are connected in sequence. The negative power supply terminal of the third amplifier A3 ( Figure 4 the position marked 2 of the third amplifier in Figure 4 ) is connected to the negative pole of the power supply. The negative input terminal of the third amplifier A3 ( Figure 4 the position marked 4 of the third amplifier in Figure 4It is connected to the position marked 4 of the fourth amplifier, and one end of the twenty-fourth resistor R24, and the other end of the twenty-fourth resistor R24 is connected to the output terminal check OUT of the fourth amplifier A4.

[0076] Meanwhile, the negative power supply terminal of the fourth amplifier A4 ( Figure 4 at the position marked 2 of the fourth amplifier in [[]]) is connected to the negative power supply. The positive power supply terminal of the fourth amplifier A4 ( Figure 4 at the position marked 5 of the fourth amplifier in [[]]) is respectively connected to the positive power supply VCC and one end of the fifth capacitor C5, and the other end of the fifth capacitor C5 is connected to the negative power supply.

[0077] Furthermore, the display circuit includes a third triode Q3, a fourth triode Q4, a twelfth resistor R12, an eighth resistor R8, a bi-color diode DS1, and a ninth resistor R9. The bases of the third triode Q3 and the fourth triode Q4 are both connected to the output terminal check OUT of the fourth amplifier A4 in the differential circuit through the twelfth resistor R12. The emitter of the third triode Q3 is connected to the positive power supply VCC through the eighth resistor R8, and the collector of the third triode Q3 is connected to the first end of the bi-color diode DS1 (specifically, the green light end of the bi-color diode). Among them, the third triode Q3 is of the PNP type, and the fourth triode Q4 is of the NPN type.

[0078] Meanwhile, the emitter of the fourth triode Q4 is connected to the second end of the bi-color diode DS1 (specifically, the red light end of the bi-color diode), the common terminal of the bi-color diode DS1 is connected to the negative power supply, and the collector of the fourth triode Q4 is connected to the positive power supply VCC through the ninth resistor R9.

[0079] Based on the above description, through the connection between the differential circuit and the display circuit, the bi-color diode DS1 in the display circuit indicates whether the status indicator light is in a normal working state. Specifically, the working principle of the first monitoring circuit is as follows:

[0080] Since the light-emitting conduction voltage of the status indicator light is 2.0V, and this voltage does not change with the change of the external voltage. When there is no problem with the quality of the status indicator light itself, the status indicator light can conduct normally. For example, at this time, the voltage of the positive electrode check+ of the status indicator light is 2.7V, and the second amplifier A2 amplifies the 2.7V voltage to 4V.

[0081] At the same time, the third amplifier A3 is used to amplify the voltage of the negative electrode check- of the status indicator light, wherein, regardless of whether the status indicator light is turned on or not, the voltage of the negative electrode check- of the status indicator light is pulled down to the ground through the third end of the second photocoupler U2, that is, the second photocoupler U2 can reduce the voltage of the negative electrode check- of the status indicator light, for example, the reduced voltage value is 0.7V, and at this time, the third amplifier A3 can amplify the voltage of the negative electrode check- of the status indicator light to 4V.

[0082] Furthermore, the second amplifier A2 and the third amplifier A3 both input the amplified voltages to the fourth amplifier A4, and the fourth amplifier A4 is used to amplify the difference between the voltage output by the second amplifier A2 and the voltage output by the third amplifier A3.

[0083] Among them, when the output voltages of the output terminal check+OUT of the second amplifier A2 and the output terminal check-OUT of the third amplifier A3 are both 4V, the output voltage of the output terminal check OUT of the fourth amplifier A4 is 0V. At this time, the third transistor Q3 is turned on, that is, the green light in the two-color diode DS1 is on, which proves that the status indicator light itself has no fault and the extinction of the status indicator light has nothing to do with its own quality.

[0084] When the status indicator light has a quality problem, the status indicator light is in an open circuit state. At this time, the positive electrode check+ of the status indicator light, the eleventh resistor R11 and the positive power supply electrode VCC are connected, that is, at this time, the voltage of the status indicator light is equal to the voltage of the positive power supply electrode VCC, which is 5V, and reaches the saturation voltage of the second amplifier A2. After amplification by the second amplifier A2, the output voltage is still 5V.

[0085] At the same time, the voltage output by the third amplifier A3 is 4V, that is, the difference between the output voltages of the second amplifier A2 and the third amplifier A3 is 1V, and the voltage output by the output terminal check OUT of the fourth amplifier A4 is greater than 0V, so that the fourth transistor Q4 is turned on, that is, the red light in the two-color diode DS1 is on, which proves that the status indicator light is off due to its own quality reasons, and the status indicator light needs to be repaired.

[0086] The difference between the positive voltage of the status indicator light and the negative voltage of the status indicator light after the above calculation and amplification can be used to determine whether the status indicator light is invalid, which can achieve the technical effect of improving the simplicity of quality detection of the status indicator light. At the same time, by using the different colors of the two-color diode to identify whether the status indicator light is faulty, this visual detection result can improve the technical effect of the simplicity of the staff to understand the detection results.

[0087] Of course, in other embodiments, the differential circuit and the display circuit may be adjusted and replaced according to different circuit functions.

[0088] In addition, as shown in Figure 5 , the second monitoring circuit 3 includes a fourth capacitor C4, a nineteenth resistor R19, and a fifth diode D5. One end of the fourth capacitor C4 is connected to the positive power supply VCC, and the other end of the fourth capacitor C4 is connected to the negative power supply. The first end of the AC / DC converter AC / DC2, the connection point between the fourth capacitor C4 and the positive power supply VCC, the nineteenth resistor R19, and the positive electrode of the fifth diode D5 are connected in sequence, and the negative electrode of the fifth diode D5 is connected to the negative power supply. Among them, the fifth diode is a light-emitting diode.

[0089] When the status indicator is off, if the fifth diode D5 is also off, it can be proved at this time that the second monitoring circuit is not conducting, that is, there is a fault in the power supply circuit, and there is no power output at this time, and the power supply circuit needs to be repaired. When the status indicator is off and the fifth diode D5 emits light, it proves that the power supply circuit is not faulty and the power supply protection circuit of the status indicator is effective. Based on this, it is possible to judge whether the extinguishing of the status indicator is due to the self-failure of the surge indicator or the failure of the power supply circuit of the status indicator, so as to achieve the technical effect of improving the accuracy of surge protector failure monitoring.

[0090] In addition, as shown in Figure 6 , the surge protector further includes a disconnection detection circuit. The disconnection detection circuit is connected to the negative electrode check- of the status indicator and is used to detect the on / off of the internal circuit of the status indicator itself, which can further avoid the occurrence of false alarms of the status indicator due to internal cable faults or loose plugs of the status indicator itself, so as to improve the accuracy of the status indicator indicating the working status of the surge protector.

[0091] Among them, the disconnection detection circuit includes a fifth amplifier A5, a twenty-eighth resistor R28, a seventh diode D7, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a twenty-fifth resistor R25, and a sixth capacitor C6. The output terminal of the fifth amplifier A5 ( Figure 6 the position marked 1 of the fifth amplifier in

[0092] ), the twenty-eighth resistor R28, and the positive electrode of the seventh diode D7 are connected in sequence, and the negative electrode of the seventh diode D7 is connected to the negative power supply. Among them, the seventh diode is a light-emitting diode. Figure 6 At the same time, the negative power supply terminal of the fifth amplifier A5 ( Figure 6 the position marked 2 of the fifth amplifier inFigure 6 the position marked 4 of the fifth amplifier (in the figure), the twenty-fifth resistor R25, and the negative electrode check- of the status indicator are connected in sequence. The positive power supply terminal of the fifth amplifier A5 ( Figure 6 the position marked 5 of the fifth amplifier in the figure) is respectively connected to the positive power supply VCC and one end of the sixth capacitor C6, and the other end of the sixth capacitor C6 is connected to the negative power supply.

[0093] Based on the above discussion, when the status indicator is off and the seventh diode D7 emits light, it can be proved that the cable connection between the negative electrode check- of the status indicator and the second port Port2 of the first monitoring circuit is normal, and the extinguishing of the status indicator is not caused by the cable or plug of the status indicator. That is, the circuit of the positive power supply VCC, the eleventh resistor R11, the status indicator, the second optocoupler U2, and the negative power supply is a conducting path.

[0094] Specifically, the reason for the seventh diode D7 to emit light is as follows: Since the 0.7V voltage in the second optocoupler U2 is amplified by the fifth amplifier A5, it can drive the seventh diode D7 to emit light.

[0095] When the status indicator is off and the seventh diode D7 is also off, there is a cable connection fault between the negative electrode check- of the status indicator and the second port Port2 of the first monitoring circuit, which can prove that the extinguishing of the status indicator is at least related to the power supply circuit. That is to say, the circuit of the positive power supply VCC, the eleventh resistor R11, the status indicator, the second optocoupler U2, and the negative power supply is an open circuit.

[0096] Specifically, the reason for the seventh diode D7 to be off is as follows: When the plug is loose or the cable is disconnected due to stress between the negative electrode check- of the status indicator and the second port Port2 of the first monitoring circuit, the negative electrode check- of the status indicator is suspended, and the voltage of the negative electrode check- of the status indicator is the power supply voltage, which is higher than the voltage of the non-inverting input terminal of the fifth amplifier A5. Therefore, the output voltage of the output terminal of the fifth amplifier is 0V, and thus, the seventh diode D7 is off.

[0097] That is, by connecting the disconnection detection circuit to the status indicator and using the seventh diode, the connection of the cable and plug of the status indicator can be detected, which can avoid the false alarm of the status indicator and affect the judgment of the effectiveness of the surge protector, thereby achieving the technical effect of improving the accuracy of the judgment of the working effectiveness of the surge protector.

[0098] In addition, combined with Figure 7As shown, the surge protector further includes a fault indication circuit. The fault indication circuit is connected between the second end of the second optocoupler U2 and the neutral line, and is used to regularly check the effectiveness of the protection circuit to ensure that the lighting and extinguishing of the status indicator are in a normal indication state.

[0099] In addition, in combination with Figure 7 As shown, the fault indication circuit includes a relay K1, a first triode Q1, a second resistor R2, a self-check switch S1, a first resistor R1, a second triode Q2, a second diode D2, a first diode D1, a third resistor R3, and a sixth resistor R6.

[0100] Among them, the first contact of the relay K1 ( Figure 7 the position marked 1 in the relay) is connected to the second end of the second optocoupler U2, and the second contact of the relay K1 ( Figure 7 the position marked 2 in the relay) is connected to the collector of the first triode Q1. Among them, the first triode Q1 is of NPN type.

[0101] Further, the emitter of the first triode Q1 is connected to the negative power supply, the base of the first triode Q1 is respectively connected to one end of the second resistor R2 and one end of the first resistor R1, the other end of the second resistor R2 is connected to the positive power supply VCC through the self-check switch S1, and the other end of the first resistor R1 is connected to the base of the second triode Q2. The emitter of the second triode Q2, the positive pole of the second diode D2, the negative pole of the second diode D2, and the negative pole check- of the status indicator are connected in sequence. The collector of the second triode Q2, the negative pole of the first diode D1, the positive pole of the first diode D1, the third resistor R3, and the positive power supply VCC are connected in sequence. Among them, the first diode D1 is a light-emitting diode, and the second triode Q2 is of NPN type.

[0102] Furthermore, the seventh contact of the relay K1 ( Figure 7 the position marked 7 in the relay) is connected to the neutral line N, the sixth contact of the relay K1 ( Figure 7 the position marked 6 in the relay), the sixth resistor R6, and the positive power supply VCC are connected in sequence, and the first contact or the fourteenth contact of the relay K1 ( Figure 7 the position marked 14 in the relay) can be connected to the seventh contact of the relay K1.

[0103] Specifically, when the self-check switch S1 is in the normally open state, the relay K1 is not attracted. At this time, the first contact of the relay K1 is conducted with the seventh contact of the relay K1, and the positive power supply VCC, the status display lamp, the second optocoupler U2, the relay K1, and the neutral line N in the fault indication circuit are conducted, so that the loop of the status indicator is conducted and the status indicator lights up.

[0104] When it is necessary to check the indication function status of the status indicator light, turn off the self-check switch S1. The first triode Q1 conducts, causing the coil of the relay K1 to be energized. At this time, the fourteenth contact of the relay K1 is conducted with the seventh contact of the relay K1, and the first contact of the relay K1 is disconnected from the seventh contact of the relay K1. The status indicator light goes out due to the disconnection of the circuit. At the same time, the second triode Q2 conducts, and a path is formed among the positive power supply VCC, the third resistor R3, the first diode D1, the second triode Q2, the second diode D2, the negative pole check- of the status indicator light, and the negative power supply in the fault indication circuit, that is, the first diode emits light, which proves that the indication function of the status indicator light is in a normal state, and proves that the on / off of the status indicator light and the working effectiveness of the protection circuit indicating the surge protector are accurate. After the inspection is completed, then control the self-check switch S1 to be in the normally open state. At this time, the status indicator light emits light and the first diode goes out, completing a disconnection inspection. Based on this, the reliability of the fuse and the protection circuit can be detected through the self-check switch before leaving the factory, and the technical effects of improving the accuracy and reliability of the working effectiveness of the surge protector can be achieved.

[0105] In addition, in combination with Figure 7 as shown, the fault indication circuit further includes a third optocoupler U3, a twenty-ninth resistor R29, a sixth triode Q6, a thirtieth resistor R30, and a redundant display element.

[0106] Among them, the third optocoupler U3 is connected between the seventh contact of the relay K1 and the neutral line N. At this time, the closed loop of the above-mentioned fault indication circuit is adjusted from "positive power supply VCC, status display light, second optocoupler U2, relay K1, and neutral line N" to "positive power supply VCC, status display light, second optocoupler U2, relay K1, third optocoupler U3, and neutral line N".

[0107] Furthermore, the second terminal of the third optocoupler U3 ( Figure 7 the position marked 2 of the third optocoupler in Figure 7 ) is connected to the neutral line N, and the first terminal of the third optocoupler U3 (combined with Figure 7 the position marked 1 of the third optocoupler in Figure 7The positions marked 3 of the third optocoupler are respectively connected to one end of the twenty-ninth resistor R29 and the base of the sixth triode Q6. The other end of the twenty-ninth resistor R29 is connected to the negative power supply, and the emitter of the sixth triode Q6 is connected to the negative power supply. The collector of the sixth triode Q6, the thirtieth resistor R30, the negative pole of the redundant display element, the positive pole of the redundant display element, and the positive power supply VCC are connected in sequence. Among them, the sixth triode Q6 is an NPN type.

[0108] Based on this, in the normal working state, that is, when the self-check switch S1 is in the normally open state, the third optocoupler U3 is in the conducting state, that is, the third terminal and the fourth terminal of the third coupler are conducting, making the sixth triode Q6 conducting, and further making the redundant display element conducting. Through the redundant display element, it can be proved that the surge protector is in an effective state. Even if the status indicator light goes out due to false alarm, the redundant display element can still emit light, enabling the surge protector to be used normally without replacement and maintenance, thus achieving the technical effect of reducing the use cost of the surge protector.

[0109] Furthermore, preferably, in this embodiment, the redundant display element is a light-emitting element, which can improve the visibility of the redundant display element and the simplicity for the staff to understand the working state of the surge protector. Among them, the light-emitting element is a light-emitting diode D8. Based on this, the seismic resistance of the light-emitting element can be improved, thereby achieving the improvement of the reliability of the redundant display element.

[0110] Of course, in other embodiments, the fault indication circuit can also select other redundant display elements according to different circuit designs, such as a voltmeter.

[0111] The above is only the specific implementation manner of the present invention. Under the above teaching of the present invention, those skilled in the art can make other improvements or deformations based on the above embodiments. Those skilled in the art should understand that the above specific description is only to better explain the purpose of the present invention, and the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A surge protector, characterized in that: It includes a lightning protection circuit, a first monitoring circuit and a second monitoring circuit; The lightning protection circuit comprises a power supply protection circuit and a status indicator light which are sequentially connected between the positive power supply electrode and the negative power supply electrode; the status indicator light is used to indicate whether the lightning protection circuit fails; The first monitoring circuit is connected to the status indicator light and is used to monitor whether the status indicator light fails; the second monitoring circuit is connected to the power supply protection circuit and is used to monitor whether the power supply protection circuit fails.

2. The surge protector according to claim 1, characterized in that: The first monitoring circuit includes a differential circuit and a display circuit; The two input ends of the differential circuit are respectively connected to the positive and negative poles of the status indicator light, and the output end of the differential circuit is connected to the display circuit for calculating the difference between the amplified positive voltage of the status indicator light and the negative voltage of the status indicator light. The display circuit is used to indicate whether the status indicator light is faulty.

3. The surge protector according to claim 2, characterized in that: The display circuit includes a third triode, a fourth triode, a twelfth resistor, an eighth resistor, a two-color diode and a ninth resistor; The base of the third transistor and the base of the fourth transistor are both connected to the differential circuit through the twelfth resistor; The emitter of the third triode is connected to the positive power supply electrode through the eighth resistor, and the collector of the third triode is connected to the first end of the two-color diode; The emitter of the fourth triode is connected to the second end of the two-color diode, and the common end of the two-color diode is connected to the negative power supply electrode; the collector of the fourth triode, the ninth resistor and the positive power supply electrode are connected in sequence.

4. The surge protector according to claim 1, characterized in that: The second monitoring circuit includes a fourth capacitor, a nineteenth resistor and a fifth diode; The anodes of the fourth capacitor, the nineteenth resistor and the fifth diode are connected in sequence, the cathode of the fifth diode is connected to the negative power supply electrode, the fourth capacitor is connected to the power supply protection circuit, and the fifth diode is a light emitting diode.

5. The surge protector according to claim 1, characterized in that: Also includes a fault indication circuit; The lightning protection circuit also includes a second photoelectric coupler; the fourth end of the second photoelectric coupler is connected to the negative electrode of the status indicator light, the first end of the second photoelectric coupler is connected to the power supply protection circuit; the third end of the second photoelectric coupler is connected to the negative electrode of the power supply; The fault indication circuit is connected to the second end of the second photoelectric coupler and is used to detect the on / off state of the power supply protection circuit.

6. The surge protector according to claim 5, characterized in that: The fault indication circuit includes a relay, a first triode, a second resistor, a self-checking switch, a first resistor, a second triode, a second diode, a first diode, a third resistor and a sixth resistor; The first contact of the relay is connected to the second end of the second photocoupler; the second contact of the relay is connected to the collector of the first transistor, the emitter of the first transistor is connected to the negative power supply electrode, the base of the first transistor is respectively connected to one end of the second resistor and one end of the first resistor, and the other end of the second resistor is connected to the positive power supply electrode through the self-test switch; the other end of the first resistor is connected to the base of the second transistor; The emitter of the second triode, the second diode and the cathode of the status indicator light are connected in sequence, the collector of the second triode, the first diode, the third resistor and the positive electrode of the power supply are connected in sequence, and the first diode is a light emitting diode; The sixth contact of the relay, the sixth resistor and the positive power supply electrode are connected in sequence; The first contact of the relay or the fourteenth contact of the relay can be connected to the seventh contact of the relay; The seventh contact of the relay is connected to the neutral line; When the self-test switch is in a normally open state, the first contact of the relay is connected to the seventh contact of the relay; when the self-test switch is in a closed state, the fourteenth contact of the relay is connected to the seventh contact of the relay.

7. The surge protector according to claim 6, characterized in that: The fault indication circuit also includes a third photoelectric coupler, a twenty-ninth resistor, a sixth transistor, a thirtieth resistor and a redundant display element; The seventh contact of the relay is connected to the neutral line through the second end of the third photoelectric coupler, and the first end of the third photoelectric coupler is connected to the seventh contact of the relay; the fourth end of the third photoelectric coupler is connected to the positive power supply electrode; The third end of the third photocoupler is respectively connected to one end of the twenty-ninth resistor and the base of the sixth transistor, the other end of the twenty-ninth resistor and the emitter of the sixth transistor are respectively connected to the negative power supply electrode, and the collector of the sixth transistor, the thirtieth resistor, the redundant display element and the positive power supply electrode are connected in sequence.

8. The surge protector according to claim 7, characterized in that: The redundant display element is a light emitting element.

9. The surge protector according to any one of claims 1 to 8, characterized in that: It also includes a disconnection detection circuit; the disconnection detection circuit is connected to the negative pole of the status indicator light and is used to detect the on-off of the internal circuit of the status indicator light itself.

10. The surge protector according to claim 9, characterized in that: The disconnection detection circuit includes a fifth amplifier, a twenty-eighth resistor, a seventh diode, a twenty-sixth resistor, a twenty-seventh resistor, a twenty-fifth resistor and a sixth capacitor; The output end of the fifth amplifier, the twenty-eighth resistor and the anode of the seventh diode are connected in sequence, the cathode of the seventh diode is connected to the negative power supply electrode, the seventh diode is a light emitting diode, and the negative power supply end of the fifth amplifier is connected to the negative power supply electrode; The positive input terminal of the fifth amplifier is respectively connected to one end of the twenty-sixth resistor and one end of the twenty-seventh resistor, the other end of the twenty-sixth resistor is connected to the negative power supply electrode, and the other end of the twenty-seventh resistor is connected to the positive power supply electrode; The negative input terminal of the fifth amplifier, the twenty-fifth resistor and the negative electrode of the status indicator light are connected in sequence; The positive power supply terminal of the fifth amplifier is connected to the positive power supply electrode and one end of the sixth capacitor respectively, and the other end of the sixth capacitor is connected to the negative power supply electrode.

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