CN113917219A - Automatic detection alarm device - Google Patents
Automatic detection alarm device Download PDFInfo
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- CN113917219A CN113917219A CN202111173226.8A CN202111173226A CN113917219A CN 113917219 A CN113917219 A CN 113917219A CN 202111173226 A CN202111173226 A CN 202111173226A CN 113917219 A CN113917219 A CN 113917219A
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- current
- alarm
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- optical coupler
- detection circuit
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/145—Indicating the presence of current or voltage
- G01R19/15—Indicating the presence of current
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/22—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using light-emitting devices, e.g. LED, optocouplers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/145—Indicating the presence of current or voltage
- G01R19/155—Indicating the presence of voltage
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- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
The invention discloses an automatic detection alarm device, which is used for detecting a junction box and comprises: the voltage detection circuit comprises a full-wave rectification circuit and an optocoupler, and the full-wave rectification circuit is respectively connected with a fire wire end and a zero wire end of the detection junction box; the optical coupler is connected with a full-wave rectifying circuit, and the full-wave rectifying circuit is used for converting alternating current into direct current to be input into the optical coupler; the first alarm is connected with the output end of the optocoupler, and the optocoupler is used for driving the first alarm to operate; the current detection circuit comprises an integrated operational amplifier and a diode, wherein the integrated operational amplifier is connected with a current inlet end of the junction box and is used for amplifying current input by the junction box; the diode is connected with the output end of the operational amplifier and is used for carrying out unidirectional rectification on the current; the second alarm is connected with the output end of the diode, and the current detection circuit is used for driving the second alarm to operate.
Description
Technical Field
The invention relates to the technical field of power detection equipment, in particular to an automatic detection alarm device.
Background
The electricity meter is a meter for measuring consumption of electric energy and consumption speed, which is indispensable in the power transmission and distribution line. When using the ammeter, need install the ammeter on the ammeter case, current ammeter case installation is accomplished the back, and a lot of customers need to be changed and are qualified for the next round of competitions or will appear temporarily removing, and power supply personnel must arrive the scene and assist the customer to remove seal and ammeter case lid, change trouble electric energy meter, the work that power supply company measurement professional staff often goes on, account for in the measurement work than 80%.
When the trouble electric energy meter is changed, because of receiving influences such as power supply mode or customer power consumption nature, often can not change after taking the power failure measure, need electrified change, at this moment, demolish behind the trouble electric energy meter, former electric energy meter binding post end of a thread is exposed, for the sake of safety, although can wrap up the exposed end of a thread with insulating adhesive tape, it is all more troublesome to wrap up and demolish the adhesive tape, in the work of actually electrified meter change, the staff often does not wrap up, therefore, the staff takes place people's electric shock or short circuit electric arc burns very easily at the in-process of changing the electric energy meter, serious probably causes personnel to electrocute, have great personal risk.
In view of this, need to the prior art in the process of changing the electric energy meter, the technical problem that personnel's safety is influenced to the exposure of the end of a thread of demolition.
Disclosure of Invention
The invention aims to provide an automatic detection alarm device to solve the technical problems.
In order to achieve the purpose, the invention adopts the following technical scheme:
an automatic detection alarm device for detecting a junction box, comprising: a voltage detection circuit, a current detection circuit, a first alarm and a second alarm,
the voltage detection circuit comprises a full-wave rectifying circuit and an optical coupler, and the full-wave rectifying circuit is respectively connected with a live wire end and a zero wire end of the junction box; the optical coupler is connected with the full-wave rectifying circuit, and the full-wave rectifying circuit is used for converting alternating current into direct current to be input into the optical coupler;
the first alarm is connected with the output end of the optical coupler, and the optical coupler is used for driving the first alarm to operate;
the current detection circuit comprises an integrated operational amplifier and a diode, wherein the integrated operational amplifier is connected with a current inlet end of the junction box and is used for amplifying current input by the junction box; the diode is connected with the output end of the operational amplifier and is used for carrying out unidirectional rectification on current;
the second alarm is connected with the output end of the diode, and the current detection circuit is used for driving the second alarm to operate.
Optionally, the voltage detection circuit further includes a first current-limiting resistor and a second current-limiting resistor, where the first current-limiting resistor is connected in series between the live wire end and the full-wave rectification circuit, and is configured to limit an input current of the full-wave rectification circuit;
the full-wave rectifying circuit is connected in series between the full-wave rectifying circuit and the optocoupler and used for limiting the output current of the full-wave rectifying circuit.
Optionally, the voltage detection circuit further includes a first capacitor and a second capacitor, where the first capacitor is connected in parallel with an input side of the optocoupler and is used to perform ac shunting on an input current of the optocoupler;
and the second capacitor is connected with the output side of the optical coupler in parallel and is used for carrying out alternating current shunting on the output current of the optical coupler.
Optionally, the first alarm includes a third resistor, a first LED lamp and a first buzzer, which are connected in parallel, and the first LED lamp is connected in series with a fourth resistor.
Optionally, the current detection circuit further includes a driving power supply, and an input end and an output end of the driving power supply are respectively connected to the integrated operational amplifier.
Optionally, the second alarm includes a second LED lamp and a second buzzer, which are arranged in parallel; and the second LED lamp is connected with a seventh resistor in series.
Optionally, the alarm device further comprises an insulating cover, the insulating cover is sleeved outside the junction box, the voltage detection circuit and the current detection circuit, and the first alarm and the second alarm are exposed out of the insulating cover.
Compared with the prior art, the invention has the following beneficial effects: when the voltage detection circuit works, the voltage detection circuit is connected to a live wire end and a zero line end of the junction box, the full-wave rectification circuit rectifies alternating current connected into the circuit to form first current close to direct current, the first current is input to the optocoupler, the alternating current in the first current is shunted in parallel under the shunting action of the first capacitor to form second direct current, the second direct current is input to the optocoupler, the optocoupler operates to output current under the current stabilization action of the second capacitor to form third direct current, the third direct current is output to the first alarm, and the first alarm operates to prompt a worker that working voltage exists in the circuit so as to avoid electric shock caused by mistaken touch; similarly, the working current in the junction box is input into the current detection circuit and amplified by the integrated operational amplifier to generate a larger current to drive the second alarm to operate, so that a user is prompted that the working current exists in the junction box, a safety warning effect is achieved, and mistaken touch is avoided; the automatic detection alarm device has the function of automatically detecting voltage and current, and once the current and the voltage are not in accordance with safe operation conditions, the alarm function can be triggered to remind an operator, so that electric shock is prevented from being mistakenly triggered, and the personal safety of the operator is ensured.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.
The structure, proportion, size and the like shown in the drawings are only used for matching with the content disclosed in the specification, so that the person skilled in the art can understand and read the description, and the description is not used for limiting the limit condition of the implementation of the invention, so the method has no technical essence, and any structural modification, proportion relation change or size adjustment still falls within the scope of the technical content disclosed by the invention without affecting the effect and the achievable purpose of the invention.
Fig. 1 is a schematic structural diagram of voltage detection of the automatic detection alarm device.
Fig. 2 is a schematic structural diagram of current detection of the automatic detection alarm device.
Illustration of the drawings: the alarm device comprises a voltage detection circuit 1, a current detection circuit 2, a first alarm 3, a second alarm 4, a full-wave rectification circuit 11, an optocoupler 12, a live wire end L, a zero line end N, an integrated operational amplifier 21, a diode 22, a first current-limiting resistor R1, a second current-limiting resistor R2, a first capacitor C1, a second capacitor C2, a third resistor R3, a first LED lamp 32, a first buzzer 31, a fourth resistor R4, a driving power supply 23, a second LED lamp 41, a second buzzer 42 and a seventh resistor R7.
Detailed Description
In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the embodiments described below are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. It should be noted that when one component is referred to as being "connected" to another component, it can be directly connected to the other component or intervening components may also be present.
The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.
The embodiment of the invention provides an automatic detection alarm device, which is used for detecting a junction box and comprises the following components: a voltage detection circuit 1, a current detection circuit 2, a first alarm 3 and a second alarm 4,
the voltage detection circuit 1 comprises a full-wave rectification circuit 11 and an optical coupler 12, wherein the full-wave rectification circuit 11 is respectively connected with a live wire end L and a zero wire end N of the junction box; the optical coupler 12 is connected with the full-wave rectifying circuit 11, and the full-wave rectifying circuit 11 is used for converting alternating current into direct current to be input into the optical coupler 12;
the first alarm 3 is connected with the output end of the optical coupler 12, and the optical coupler 12 is used for driving the first alarm 3 to operate;
the current detection circuit 2 comprises an integrated operational amplifier 21 and a diode 22, wherein the integrated operational amplifier 21 is connected with a current inlet end of the junction box and is used for amplifying current input by the junction box; the diode 22 is connected with the output end of the integrated operational amplifier 21 and is used for performing unidirectional rectification on current;
the second alarm 4 is connected with the output end of the diode 22, and the current detection circuit 2 is used for driving the second alarm 4 to operate.
The working principle of the invention is as follows: when the voltage detection circuit 1 works, the voltage detection circuit 1 is connected to a live wire end L and a zero line end N of the junction box, the full-wave rectification circuit 11 rectifies alternating current connected into the circuit to form first current close to direct current, the first current is input into the optical coupler 12, the alternating current in the first current is shunted in parallel through the shunting action of the first capacitor C1 to form second direct current, the second direct current is input into the optical coupler 12, the optical coupler 12 operates to output current through the current stabilization action of the second capacitor C2 to form third direct current, the third direct current is output to the first alarm 3, and the first alarm 3 operates to prompt a worker that working voltage exists in the circuit so as to avoid electric shock caused by error touch; similarly, the working current in the junction box is input into the current detection circuit 2 and amplified by the integrated operational amplifier 21, and a larger current is generated to drive the second alarm 4 to operate, so that a user is prompted that the working current exists in the junction box, a safety warning effect is achieved, and mistaken touch is avoided; the automatic detection alarm device has the function of automatically detecting voltage and current, and once the current and the voltage are not in accordance with safe operation conditions, the alarm function can be triggered to remind an operator, so that electric shock is prevented from being mistakenly triggered, and the personal safety of the operator is ensured.
In this embodiment, the voltage detection circuit 1 further includes a first current limiting resistor R1 and a second current limiting resistor R2, where the first current limiting resistor R1 is connected in series between the live line terminal L and the full-wave rectification circuit 11, and is used for limiting the input current of the full-wave rectification circuit 11;
the full-wave rectifying circuit 11 is connected in series between the full-wave rectifying circuit 11 and the optocoupler 12, and is configured to limit an output current of the full-wave rectifying circuit 11.
The first current limiting resistor R1 has a preset first resistance value, and is used for limiting the input current of the voltage detection circuit 1, that is, setting a safe current value, and when the input current exceeds the safe current value, driving the first alarm 3 to operate.
Further illustratively, the voltage detection circuit 1 further includes a first capacitor C1 and a second capacitor C2, where the first capacitor C1 is connected in parallel with the input side of the optical coupler 12, and is used for ac shunting the input current of the optical coupler 12;
the second capacitor C2 is connected in parallel with the output side of the optocoupler 12 and is used for ac shunting the output current of the optocoupler 12. The first capacitor C1 and the second capacitor C2 respectively play a role in stabilizing current and divide alternating current in current.
In this embodiment, the first alarm 3 includes a third resistor R3, a first LED lamp 32 and a first buzzer 31, which are arranged in parallel, and the first LED lamp 32 is connected in series with a fourth resistor R4.
In this embodiment, the current detection circuit 2 further includes a driving power supply 23, and an input terminal and an output terminal of the driving power supply 23 are respectively connected to the integrated operational amplifier 21.
In the present embodiment, the second alarm 4 includes a second LED lamp 41 and a second buzzer 42 arranged in parallel; the second LED lamp 41 is connected in series with a seventh resistor R7.
In this embodiment, still include the insulating boot, the insulating boot cover is located outside terminal box, voltage detection circuit 1 and the current detection circuit 2, first alarm 3 and second alarm 4 expose in the insulating boot.
The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (7)
1. An automatic detection alarm device for detecting a junction box, comprising: a voltage detection circuit, a current detection circuit, a first alarm and a second alarm,
the voltage detection circuit comprises a full-wave rectifying circuit and an optical coupler, and the full-wave rectifying circuit is respectively connected with a live wire end and a zero wire end of the junction box; the optical coupler is connected with the full-wave rectifying circuit, and the full-wave rectifying circuit is used for converting alternating current into direct current to be input into the optical coupler;
the first alarm is connected with the output end of the optical coupler, and the optical coupler is used for driving the first alarm to operate;
the current detection circuit comprises an integrated operational amplifier and a diode, wherein the integrated operational amplifier is connected with a current inlet end of the junction box and is used for amplifying current input by the junction box; the diode is connected with the output end of the operational amplifier and is used for carrying out unidirectional rectification on current;
the second alarm is connected with the output end of the diode, and the current detection circuit is used for driving the second alarm to operate.
2. The automatic detection alarm device according to claim 1, wherein the voltage detection circuit further comprises a first current limiting resistor and a second current limiting resistor, the first current limiting resistor is connected in series between the live wire end and the full-wave rectification circuit for limiting an input current of the full-wave rectification circuit;
the full-wave rectifying circuit is connected in series between the full-wave rectifying circuit and the optocoupler and used for limiting the output current of the full-wave rectifying circuit.
3. The automatic detection alarm device according to claim 2, wherein the voltage detection circuit further comprises a first capacitor and a second capacitor, the first capacitor is connected in parallel with the input side of the optical coupler and is used for alternating current shunting of the input current of the optical coupler;
and the second capacitor is connected with the output side of the optical coupler in parallel and is used for carrying out alternating current shunting on the output current of the optical coupler.
4. The automatic detection alarm device according to claim 1, wherein the first alarm comprises a third resistor, a first LED lamp and a first buzzer, which are arranged in parallel, and the first LED lamp is connected with a fourth resistor in series.
5. The automatic detection alarm device of claim 1, wherein the current detection circuit further comprises a driving power supply, and an input end and an output end of the driving power supply are respectively connected with the integrated operational amplifier.
6. The automatic detection alarm device according to claim 1, wherein the second alarm comprises a second LED lamp and a second buzzer arranged in parallel; and the second LED lamp is connected with a seventh resistor in series.
7. The automatic detection alarm device according to claim 1, further comprising an insulating cover, wherein the insulating cover is sleeved outside the junction box, the voltage detection circuit and the current detection circuit, and the first alarm and the second alarm are exposed out of the insulating cover.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111173226.8A CN113917219A (en) | 2021-10-08 | 2021-10-08 | Automatic detection alarm device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111173226.8A CN113917219A (en) | 2021-10-08 | 2021-10-08 | Automatic detection alarm device |
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| Publication Number | Publication Date |
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| CN113917219A true CN113917219A (en) | 2022-01-11 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111173226.8A Pending CN113917219A (en) | 2021-10-08 | 2021-10-08 | Automatic detection alarm device |
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