CN111751778A - Detection system and method for reliable access of electric energy meter calibration instrument - Google Patents
Detection system and method for reliable access of electric energy meter calibration instrument Download PDFInfo
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- CN111751778A CN111751778A CN202010430287.7A CN202010430287A CN111751778A CN 111751778 A CN111751778 A CN 111751778A CN 202010430287 A CN202010430287 A CN 202010430287A CN 111751778 A CN111751778 A CN 111751778A
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- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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- G01R35/04—Testing or calibrating of apparatus covered by the other groups of this subclass of instruments for measuring time integral of power or current
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Abstract
The invention provides a system and a method for detecting reliable access of an electric energy meter calibrator, which comprises the following steps: the method comprises the steps that an existing calibration instrument is connected into a detection tool, the detection tool is inserted into a first preset position of an intelligent junction box, a first branch is connected, and a second branch is disconnected; collecting main loop current through a first sampling circuit, collecting first branch circuit current through a second sampling circuit, and comparing the main loop current with the first branch circuit current through a processor to determine whether the current calibration instrument is normally connected into a current loop; and after the current calibration instrument is normally connected into the main loop, the detection tool is continuously inserted into a second preset position in the junction box, so that the current calibration instrument can detect the electric energy meter. The current in the corresponding branch is acquired through the first sampling circuit and the second sampling circuit, and whether the current-correcting instrument is accurately connected into the loop is determined through the processor, so that the detection precision of the current-correcting instrument is improved, the field detection efficiency is improved, and potential safety hazards are eliminated.
Description
Technical Field
The invention relates to the technical field of electric energy meter measurement, in particular to a system and a method for detecting reliable access of a calibration instrument of an electric energy meter.
Background
The electric energy meter is a metering device for metering the electricity consumption of electric power users in electric power enterprises, ensures accurate metering of the electric energy meter, is responsible for the electric energy meter users, and is directly related to the economic benefits of the related electric power enterprises. With the continuous and rapid development of economy in China, the living standard of people is greatly improved, and the demand on electric power is more and more serious. The user detects or retrieves it before new electric energy meter uses or after old electric energy meter uses, generally uses present school appearance to measure it, and among the prior art, when present school appearance carries out the on-the-spot inspection to on-the-spot three-phase electric energy meter, there are potential safety hazard, wiring complicacy, data acquisition inefficiency scheduling problem.
Disclosure of Invention
In view of this, the invention provides a system and a method for detecting reliable access of an electric energy meter calibration instrument, and aims to solve the problems of low efficiency and potential safety hazard when the existing calibration instrument is used for detecting the electric energy meter in the prior art.
In one aspect, the present invention provides a system for detecting reliable access of a calibration instrument of an electric energy meter, including: detecting a tool and an intelligent junction box; the junction box is internally provided with a first branch, a second branch and a third branch which are connected in parallel; the first branch is provided with a first resistor; the second branch is provided with a normally closed branch switch for controlling the on-off of the branch; the third branch is provided with two current terminals for connecting with a current calibration instrument; the detection tool comprises: the device comprises a controller, a processor, a first sampling circuit and a second sampling circuit; the first sampling circuit is used for collecting voltage on a main loop, and the main loop is electrically connected with a current input end and a current output end of each branch circuit; two poles of the second sampling circuit are electrically connected with two ends of the second resistor; the controller is electrically connected with the first sampling circuit and the second sampling circuit and used for controlling the first sampling circuit to collect voltage on a main loop and controlling the second sampling circuit to collect voltage at two ends of the second resistor; the processor is electrically connected with the controller and used for receiving the main loop voltage signal and the voltage signals at the two ends of the second resistor and calculating a main loop current and a first branch current according to the main loop voltage signal and the voltage signals at the two ends of the second resistor.
Furthermore, in the detection system for reliable access of the electric energy meter calibration instrument, two poles of the first sampling circuit are respectively connected with a first resistor and a main loop mutual inductor, and the first resistor and the main loop mutual inductor are arranged in parallel.
Further, in the above-mentioned detecting system that electric energy meter school appearance reliably inserts, still include: a relay; wherein, the coil of relay with the controller is connected, the contact setting of relay is in first branch is gone up.
Further, in the above detection system for reliable access of the electric energy meter, the processor is provided with a calculation unit for comparing the main loop current with the first branch current, so as to determine that the current meter is accurately connected to the current test loop when a ratio of the first branch current to the main loop current is greater than a preset value and less than 1.
Further, in the detection system for reliable access of the electric energy meter calibration instrument, a first pole of the main loop is connected with a first pole of a power supply, a second pole of the main loop is connected with the first pole of the electric energy meter, and a second pole of the electric energy meter is connected with the second pole of the power supply.
Further, in the detection system that the electric energy meter calibrator reliably accessed, a power supply is further arranged in the detection tool.
Further, among the detecting system that above-mentioned electric energy meter school appearance reliably accessed, it still includes still to detect the frock: a housing; the intelligent junction box comprises a shell, a detection tool and a detection tool, wherein the detection tool is arranged in the shell, and the detection tool is inserted into the intelligent junction box.
Further, in the detection system for reliable access of the electric energy meter calibration instrument, the normally closed branch switch is a mechanical switch.
On the other hand, the invention also provides a method for detecting the reliable access of the electric energy meter calibration instrument, which comprises the following steps: the method comprises the steps that an existing calibration instrument is connected into a detection tool, the detection tool is inserted into a first preset position of an intelligent junction box, a first branch is connected, and a second branch is disconnected; collecting main loop current through a first sampling circuit, collecting first branch circuit current through a second sampling circuit, and comparing the main loop current with the first branch circuit current through a processor to determine whether the current calibration instrument is normally connected into a current loop; and after the current calibration instrument is normally connected into the main loop, the detection tool is continuously inserted into a second preset position in the junction box, so that the current calibration instrument can detect the electric energy meter.
Further, in the method for detecting reliable access of the electric energy meter calibration instrument, when the ratio of the first branch circuit current to the main circuit current is greater than a preset value and less than 1, it is determined that the calibration instrument is accurately connected to the current circuit.
According to the detection system and the detection method for reliable access of the electric energy meter, the three parallel branches are arranged in the junction box, the currents in the corresponding branches are collected through the first sampling circuit and the second sampling circuit, and then whether the current passes through the branch where the current meter is located is judged after calculation through the processor, so that whether the current meter is accurately accessed into the loop is determined, the detection precision of the current meter is improved, the field detection efficiency is improved, and potential safety hazards are eliminated.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
fig. 1 is a schematic view of a current loop of a detection system to which an electric energy meter calibration instrument is reliably connected according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of an intelligent junction box into which a detection tool is inserted in a detection system for reliable access of an electric energy meter calibration provided by an embodiment of the invention;
fig. 3 is a schematic structural diagram of an intelligent junction box in a detection system for reliable access of an electric energy meter according to an embodiment of the present invention.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
Referring to fig. 1, the system for detecting reliable access of the electric energy meter calibration instrument according to the embodiment of the present invention includes: detecting a tool and an intelligent junction box; the junction box is internally provided with a first branch, a second branch and a third branch which are connected in parallel; a second resistor R2 is arranged on the first branch circuit; the second branch is provided with a normally closed branch switch for controlling the on-off of the branch; the third branch is provided with two current terminals for connecting with a current calibration instrument; the detection tool comprises: the device comprises a controller, a processor, a first sampling circuit and a second sampling circuit; the first sampling circuit is used for collecting voltage on a main loop, and the main loop is electrically connected with a current input end and a current output end of each branch circuit; two poles of the second sampling circuit are electrically connected with two ends of the second resistor; the controller is electrically connected with the first sampling circuit and the second sampling circuit and used for controlling the first sampling circuit to collect voltage on a main loop and controlling the second sampling circuit to collect voltage at two ends of the second resistor;
the processor is electrically connected with the controller and used for receiving the main loop voltage signal and the voltage signals at the two ends of the second resistor and calculating a main loop current and a first branch current according to the main loop voltage signal and the voltage signals at the two ends of the second resistor.
Referring to fig. 2, the detection tool further includes: a housing 10; the controller, the processor, the first sampling circuit and the second sampling circuit are all arranged in the shell, and a plurality of safety bolts 11 are arranged at the bottom of the shell and used for limiting the stroke of the detection tool inserted into the intelligent junction box, for example, the stroke is about 10 mm. In this embodiment, be provided with two safety bolts on the binding post that detects frock bottom one side, can manually pull the safety bolt to detect the frock and insert the preset position department in the intelligent terminal box. And a power supply is also arranged in the detection tool and used for supplying power to the controller and the processor. An interface is arranged in the detection tool, and a current and voltage test line of the current and voltage calibration instrument can be inserted into the detection tool through the corresponding interface.
Referring to fig. 3, a protective cover is disposed on the top of the intelligent junction box, and the protective cover may be made of a transparent material. The intelligent junction box is provided with an interface 20 matched with the safety plug.
In a specific implementation manner of this embodiment, two poles of the first sampling circuit are respectively connected to a first resistor R1 and a main loop transformer L1, the first resistor R1 and the main loop transformer L1 are arranged in parallel, and a voltage across the resistor R1 can be detected by the main loop transformer, so as to calculate a main loop current I0.
The normally closed branch switch arranged on the second branch is a mechanical switch, and the on and off of the mechanical switch are manually operated (normally in an on state, so that the use of the electric energy meter is not influenced).
The main loop is electrically connected with the current input end and the current output end of each branch. The first pole of the main loop is connected with the positive pole of the power supply, the second pole of the main loop is connected with the positive pole of the electric energy meter, and the negative pole of the electric energy meter is connected with the negative pole of the power supply.
The current calibration instrument is used for field detection of a three-phase electric energy meter, a voltage module arranged in the detection tool can measure voltages (opening K1 and closing K2) at two ends of the electric energy meter, and a current module arranged in the detection tool can detect current (opening K1 and closing K2) I2 flowing through a third branch. The controller is electrically connected with the current calibration instrument and used for detecting the current of the third branch, and the processor is connected with the controller and used for receiving the current I2 flowing through the third branch and judging whether the current calibration instrument is reliably connected into the detection loop according to a preset current value. The current preset value can be determined according to actual conditions, and can be 200mA, for example.
With reference to fig. 1, the present embodiment may further include: a relay; and a coil of the relay is connected with the controller, and a contact of the relay is arranged on the first branch. The controller controls the on-off of the relay coil so as to control the opening and closing of the contact of the relay coil, and therefore the closing or opening of the first branch circuit is controlled.
For safety of field wiring, the relay is connected in series with a second resistor R2, the resistance of R2 being comparable to the internal resistance of the current terminals of the current meter, for example about 50m Ω.
The processor is provided with a calculation unit for comparing the main loop current with the first branch current to obtain a first branch current I1And the main loop current I0When the ratio of (1) is greater than a preset value and less than 1, the current calibration instrument is determined to be connected in the current test loop.
In general, the first branch current I1Less than main loop current I0And the current calibration instrument can be considered to be normally switched on. More specific preset values may be 0.3-0.6, for example when I1＞0.3I0The calibration apparatus is considered to be able to be switched on normally.
With reference to fig. 1 and 2, before field testing, the current calibration instrument is first inserted into the testing tool, and then the testing tool is inserted into the intelligent junction box for electrical connection. The current loop detection working principle is as follows: inserting a detection tool to a first position (limited by a safety plug and about 10mm of travel) of a certain interface of the intelligent junction box, automatically switching on a power supply of the detection tool, and controlling a relay K2 to be closed by a controller; manually operating to disconnect a K1 switch, and detecting whether the current calibration instrument is normally connected or not by a detection circuit; the voltage at two ends of the first resistor R1 is detected by the first sampling circuit, and the main loop current I is calculated0(ii) a Detecting the voltage across the series resistor R2 to calculate the branch current I1(ii) a If the branch current I1Less than main loop current I0(design I)1About 0.5I0) As long as I1＞0.3I0And if the current calibration instrument can be normally switched on, the safety plug can be pulled down, so that the detection tool is inserted into the second position of the interface of the intelligent junction box, the controller controls the K2 to be switched off, the K1 is switched off continuously, and the electric energy meter is detected (at the moment, the connection is in a safe state). Otherwise, the current calibration instrument is not normally connected and can not be disconnected K2, the detection service can not be carried out downwards, and the fault can be eliminated; after the detection work that present school appearance inserts finishes, will detect the frock and extract from intelligent terminal box, at first switch on mechanical switch K1, then disconnect K2, pull out at last and appear the school appearance to accomplish the detection of present school appearance to the electric energy meter.
The detection system for reliable access of the electric energy meter calibration instrument provided by the embodiment can obviously be obtained by arranging three parallel branches in the junction box, collecting current in the corresponding branches through the first sampling circuit and the second sampling circuit, and then judging whether the current passes through the branch where the current meter is located through the processor after calculation so as to determine whether the current is accurately accessed into the loop, so that the detection precision of the current meter is improved, the field detection efficiency is improved, and the potential safety hazard is eliminated.
The invention also discloses a method for detecting whether the electric energy meter calibration instrument is reliably accessed, which comprises the following steps:
step S1, the current calibration instrument is connected into a detection tool, then the detection tool is inserted into a first preset position of the intelligent junction box, the first branch is connected, and the second branch is disconnected; namely: and inserting current and voltage test wires of the current calibration instrument into the detection tool.
Step S2, collecting main loop current through a first sampling circuit, collecting first branch current through a second sampling circuit, and comparing the main loop current with the first branch current through a processor to determine whether the current calibration instrument is normally connected into a current loop;
and step S3, after the current calibration instrument is normally connected into the main loop, the detection tool is continuously inserted into a second preset position in the junction box, so that the current calibration instrument detects the electric energy meter.
Specifically, the first preset position and the second preset position in this embodiment refer to two positions with different depths in an interface corresponding to the detection tool connection terminal on the intelligent junction box, and the two preset positions respectively correspond to the on state and the off state of the first branch. The safety plug is arranged at the bottom of the detection tool to limit the stroke of the detection tool in the intelligent junction box.
And when the ratio of the first branch circuit current to the main circuit current is greater than a preset value and less than 1, determining that the current calibration instrument is accurately switched into a current circuit.
In this embodiment, the relevant parts to the system embodiment can be referred to each other, and are not described herein again.
In a specific embodiment of this embodiment, open the transparent lid of intelligent terminal box, insert the school appearance now and detect the frock, then insert the intelligent terminal box with detecting the frock. Whether the current calibration instrument is connected into the main loop or not is tested, then the safety plug is opened, the detection tool is pressed down again, calibration of the current calibration instrument on the electric energy meter is achieved, and connecting wires such as voltage and current do not need to be connected.
In summary, the three parallel branches are arranged in the junction box, the first sampling circuit and the second sampling circuit are used for collecting the current in the corresponding branch, and then the current is judged whether to pass through the branch where the current calibration instrument is located after calculation by the processor, so that whether the current calibration instrument is accurately connected into the loop is determined, the detection precision of the current calibration instrument is improved, the field detection efficiency is improved, and the potential safety hazard is eliminated.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. The utility model provides a detecting system that electric energy meter school appearance reliably inserts which characterized in that includes: detecting a tool and an intelligent junction box; wherein the content of the first and second substances,
a first branch, a second branch and a third branch which are connected in parallel are arranged in the junction box; the first branch is provided with a first resistor; the second branch is provided with a normally closed branch switch for controlling the on-off of the branch; the third branch is provided with two current terminals for connecting with a current calibration instrument;
the detection tool comprises: the device comprises a controller, a processor, a first sampling circuit and a second sampling circuit; wherein the content of the first and second substances,
the first sampling circuit is used for collecting voltage on a main loop, and the main loop is electrically connected with the current input end and the current output end of each branch circuit; two poles of the second sampling circuit are electrically connected with two ends of the second resistor;
the controller is electrically connected with the first sampling circuit and the second sampling circuit and used for controlling the first sampling circuit to collect voltage on a main loop and controlling the second sampling circuit to collect voltage at two ends of the second resistor;
the processor is electrically connected with the controller and used for receiving the main loop voltage signal and the voltage signals at the two ends of the second resistor and calculating a main loop current and a first branch current according to the main loop voltage signal and the voltage signals at the two ends of the second resistor.
2. The system for detecting reliable access of an electrical energy meter according to claim 1,
the two poles of the first sampling circuit are respectively connected with a first resistor and a main circuit mutual inductor, and the first resistor and the main circuit mutual inductor are arranged in parallel.
3. The system for detecting reliable access of an electrical energy meter according to claim 1, further comprising: a relay; wherein the content of the first and second substances,
and a coil of the relay is connected with the controller, and a contact of the relay is arranged on the first branch.
4. The system for detecting the reliable access of an electric energy meter according to claim 1, wherein a computing unit is disposed in the processor for comparing the main loop current with the first branch current to determine that the meter is correctly connected in the current test loop when a ratio of the first branch current to the main loop current is greater than a predetermined value and less than 1.
5. The system of claim 1, wherein a first pole of the primary loop is coupled to a first pole of a power source, a second pole of the primary loop is coupled to a first pole of a power meter, and a second pole of the power meter is coupled to a second pole of the power source.
6. The system for detecting reliable access of an electric energy meter according to claim 1, wherein a power supply is further arranged in the detection tool.
7. The system of claim 1, wherein the detection tool further comprises: a housing; wherein the content of the first and second substances,
the intelligent junction box comprises a shell, a detection tool and a detection tool, wherein the detection tool is arranged in the shell, and the detection tool is inserted into the intelligent junction box.
8. The system for detecting reliable access of an electrical energy meter according to claim 1, wherein the normally closed branch switch is a mechanical switch.
9. A method for detecting whether an electric energy meter is reliably accessed is characterized by comprising the following steps:
the method comprises the steps that an existing calibration instrument is connected into a detection tool, the detection tool is inserted into a first preset position of an intelligent junction box, a first branch is connected, and a second branch is disconnected;
collecting main loop current through a first sampling circuit, collecting first branch circuit current through a second sampling circuit, and comparing the main loop current with the first branch circuit current through a processor to determine whether the current calibration instrument is normally connected into a current loop;
and after the current calibration instrument is normally connected into the main loop, the detection tool is continuously inserted into a second preset position in the junction box, so that the current calibration instrument can detect the electric energy meter.
10. The method of claim 9, wherein the calibration instrument is determined to be accurately connected to the current loop when the ratio of the first branch current to the main loop current is greater than a predetermined value and less than 1.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010430287.7A CN111751778B (en) | 2020-05-20 | 2020-05-20 | Detection system and method for reliable access of electric energy meter calibration instrument |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010430287.7A CN111751778B (en) | 2020-05-20 | 2020-05-20 | Detection system and method for reliable access of electric energy meter calibration instrument |
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| CN111751778B CN111751778B (en) | 2022-10-04 |
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| CN109085401A (en) * | 2018-08-30 | 2018-12-25 | 中国电力科学研究院有限公司 | The multifunctional combined terminal box of electrical energy measurement with test fixture |
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| GB201320625D0 (en) * | 2011-04-22 | 2014-01-08 | Sichuan Elec Power Res Inst | Field integral detecting system of three-phase electric energy measuring system of electric distribution network |
| WO2012159400A1 (en) * | 2011-05-25 | 2012-11-29 | 重庆市电力公司电力科学研究院 | Online check meter of high-voltage electric energy metering device |
| CN102798838A (en) * | 2012-08-29 | 2012-11-28 | 重庆市电力公司电力科学研究院 | Pluggable safety junction box for site calibration of electric energy meter |
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