An intelligent inspection method for three-phase electric energy meter wiring in passive state

Abstract

The present invention discloses an intelligent inspection method for the wiring of a three-phase electric energy meter in a passive state, comprising: adding a meter tail disconnection detection circuit board between a joint junction box and a three-phase mutual inductor electric energy meter; connecting the three-phase electric energy meter's A, B, and C phase voltage input terminals, neutral input terminal, and all current connection terminals to the meter tail disconnection detection circuit board via coaxial terminal blocks; the meter tail disconnection detection circuit board includes a single-chip microcomputer and a relay, and switches between strong and weak current points by controlling the relay; the meter tail disconnection detection circuit board detects whether the meter tail connection has been removed or installed by detecting the connection status of two contact points on the coaxial terminal block connector, thereby ensuring that the order of disconnection of the three-phase electric energy meter's meter tail is correct. The present invention can automatically implement meter tail connection sequence inspection.

Description

Technical Field

[0001] The present invention relates to the technical field of electrician training equipment, and in particular to an intelligent inspection method for wiring of a three-phase electric energy meter in a passive state. Background Art

[0002] Electricity metering devices are crucial instruments for power companies to deliver marketing services. Routine maintenance of these devices requires meter replacements, especially when they enter their rotation cycle or when they malfunction. This is particularly important for high-quality service, requiring continuous power outages for both high-supply, high-meter and high-supply, low-meter (electricity meters connected via transformers) without disrupting users' daily lives. The complexity and risk of this work place high demands on the technical skills of those involved, necessitating training and assessment of three-phase meter installation skills. Currently, domestic methods for verifying the wiring sequence of three-phase meters in a passive state are still incomplete.

[0003] The existing products have the following problems:

[0004] The existing device cannot automatically check the wiring sequence at the end of the table. It requires trained invigilators to observe in real time with the naked eye, which increases the workload of trained invigilators. In addition, the misjudgment and missed judgment rates of wiring inspection are high, and the scoring cannot be fully automated. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides an intelligent inspection method for the wiring of a three-phase electric energy meter in a passive state, which automatically implements the wiring sequence inspection at the end of the meter.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An intelligent inspection method for wiring of a three-phase electric energy meter in a passive state, comprising:

[0008] A meter tail disconnection detection circuit board is added between the joint junction box and the three-phase mutual inductor electric energy meter. The voltage input terminals of the three-phase electric energy meter A, B, and C phases, the neutral input terminal, and all the current connection terminals are connected to the meter tail disconnection detection circuit board through coaxial terminal blocks. The meter tail disconnection detection circuit board includes a single-chip microcomputer and a relay, and switches between strong and weak current by controlling the relay.

[0009] The meter tail disconnection detection circuit board detects whether the meter tail connection is removed or installed by detecting the connection status of the two contact points on the coaxial terminal connector, and determines whether the order of disconnecting the meter tail connection of the three-phase electric energy meter is correct.

[0010] Furthermore, the coaxial terminal adopts a double-contact structure of a twin-core coaxial cable and a plug.

[0011] Furthermore, the coaxial terminal includes a conductive rod, an end conductive tube, an insulating sleeve, a tail conductive tube, a locking nut, an insulating sleeve and a double-core wire. One end of the conductive rod serves as a plug end, and the other end passes through the end conductive tube and the insulating sleeve in sequence. The conductive rod is in contact with the end conductive tube and is connected. The tail conductive tube is installed outside the insulating sleeve. The tail conductive tube and the conductive rod are insulated through the insulating sleeve. The insulating sleeve, the tail conductive tube and the conductive rod are locked with an insulating locking nut. The outer core of the wire at one end of the double-core wire is welded to the tail conductive tube, and the inner core of the wire is welded to the conductive rod. The inner and outer cores of the other end of the double-core wire are connected to the meter tail disconnection wiring detection circuit board; during detection, When the connector of the outer core and inner core of the coaxial terminal wire is inserted into the wiring hole at the tail end of the three-phase electric energy meter and the two screws on the wiring hole at the tail end of the three-phase electric energy meter are tightened, the two contact points on the coaxial terminal are short-circuited. When the two screws on the wiring hole at the tail end of the three-phase electric energy meter are loosened and the coaxial terminal connector is removed from the wiring hole at the tail end of the three-phase electric energy meter, the two contact points on the coaxial terminal plug are disconnected. The tail end wiring removal detection circuit board detects whether the tail end wiring is removed or installed by detecting the connection status of the two contact points on the coaxial terminal plug. The contact state change state combined with the sorting algorithm determines whether the order of disconnecting the tail end of the three-phase electric energy meter is correct.

[0012] Furthermore, the outside of the welding point between the inner core of the wire and the conductive rod is wrapped with an insulating sheath.

[0013] Furthermore, all current connection line terminals include the three-phase electricity meter A, B, and C phase current input terminals, the three-phase electricity meter A, B, and C phase current output terminals, plus the three-phase electricity meter A, B, and C phase voltage input terminals and neutral line input terminals, a total of 10 groups of terminal blocks are connected to the meter tail disconnection detection circuit board through coaxial terminal blocks.

[0014] Furthermore, one end of the double-core wire away from the conductive rod can be connected to a virtual load power supply.

[0015] Compared with the prior art, the present invention provides an intelligent inspection method for the wiring of a three-phase electric energy meter in a passive state, which has the following beneficial effects:

[0016] 1. Realize the functions of automatic monitoring of the meter tail disconnection sequence and automatic detection of the meter tail connection sequence;

[0017] 2. The present invention combines the intelligent guidance mode to guide students to complete the workflow training by following the correct operation process independently, thus reducing the workload of teachers;

[0018] 3. The method of automatic inspection of the three-phase meter tail connection of the present invention can realize the automatic scoring function of wiring training, and can automatically score according to the scoring requirements and the trainees' operation records, reducing the workload of teachers while improving the objectivity and accuracy of the assessment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the wiring diagram for the tail of the meter.

[0020] Figure 2 This is the system communication topology diagram.

[0021] Figure 3 This is a schematic diagram of the coaxial terminal connector.

[0022] Figure 4 This is the wiring diagram of the tail end of the table.

[0023] Figure 5 This is a schematic diagram of the wiring detection switch at the end of the meter.

[0024] Figure 6 This is a schematic diagram of the terminal structure at the end of the table.

[0025] In the figure: 1-conductive rod, 2-end conductive tube, 3-insulating sleeve, 4-tail conductive tube, 5-locking nut, 6-insulating sheath, 7-dual-core wire, 7-1-outer core of wire, 7-2-inner core of wire. DETAILED DESCRIPTION

[0026] In order to better understand the present invention, the following Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 To further clarify the content of the present invention, in the following description, numerous specific details are given to provide a more thorough understanding of the present invention.

[0027] like Figure 2 As shown, the hardware of the current comprehensive intelligent training device for operation and maintenance of electric energy metering devices mainly consists of a communication control module, a virtual load three-phase power supply, an illegal operation detection board, an incorrect wiring setting board, a combined junction box, a three-phase mutual inductor electric energy meter, a combined junction box connection status detection board and a meter tail disconnection detection circuit board. The structure of the three-phase mutual inductor electric energy meter in this embodiment is not the point protected by the present invention, and the training device of other existing electric energy metering devices can also be used, so it will not be described in detail here.

[0028] An intelligent inspection method for the wiring of a three-phase electric energy meter in a passive state comprises: adding a meter tail disconnection detection circuit board between a joint junction box of an electric energy metering device operation and maintenance training device and a three-phase mutual inductor electric energy meter, wherein the meter tail disconnection detection circuit board realizes meter tail connection and disconnection sequence detection in combination with a coaxial line terminal, and at the same time, the UA, UB, UC, and UN (respectively the voltage input terminals and neutral input terminals of the three-phase electric energy meter A, B, and C phases) voltage connection lines and IA+, IA-, IB+, IB-, IC+, and IC- (IA+, IB+, and IC+ are respectively the current input terminals of the three-phase electric energy meter A, B, and C phases) between the three-phase mutual inductor electric energy meter and the meter tail disconnection detection circuit board are connected. Figure 6 The terminals 1, 4, and 7 at the end of the meter are shown; IA-, IB-, and IC- are the current output terminals of phases A, B, and C of the three-phase energy meter, respectively. Figure 6 All current connection lines (10 sets in total) use twin-core coaxial cables with double-contact coaxial terminal blocks similar to headphone plugs. Figure 3 As shown (hereinafter referred to as coaxial terminal) connection.

[0029] The coaxial terminal includes a conductive rod 1, an end conductive tube 2, an insulating sleeve 3, a tail conductive tube 4: a locking nut 5, an insulating sleeve 6, a double-core wire 7, a wire outer core 7-1, and a wire inner core 7-2. The conductive rod 1 passes through the end conductive tube 2 and contacts and conducts with the end conductive tube 2. Then the conductive rod 1 passes through the insulating sleeve 3, and the tail conductive tube 4 is installed outside the insulating sleeve 3. The tail conductive tube 4 is insulated from the conductive rod 1 through the insulating sleeve 3. Then, the insulating locking nut 5 is used to lock it. Finally, the outer core 7-1 of the double-core wire 7 is welded to the tail conductive tube 4, and the inner core 7-2 of the double-core wire 7 is welded to the conductive rod 1. Finally, the insulating sleeve 6 is wrapped around the outside. Figure 5 The two wires of the double-core wire 7 are connected to the microcontroller interface and the virtual load three-phase power supply through a relay.

[0030] Working principle: Figure 4 As shown, when the coaxial terminal connector is inserted into the wiring hole at the end of the three-phase electric energy meter and the two screws 8 on the wiring hole at the end of the three-phase electric energy meter are tightened, the two contact points on the coaxial terminal plug will be short-circuited. When the two screws on the wiring hole at the end of the three-phase electric energy meter are loosened and the coaxial terminal connector is removed from the wiring hole at the end of the three-phase electric energy meter, the two contact points on the coaxial terminal plug will be disconnected. In this way, the meter tail wiring removal detection circuit board can detect whether the meter tail wiring is removed or installed by detecting the connection status of the two contact points on the coaxial terminal plug. By detecting the contact state change status of the 10 groups of coaxial terminal blocks at the end of the meter and combining it with a sorting algorithm, it can be determined whether the order of disconnecting the three-phase electric energy meter at the end of the meter is correct.

[0031] like Figure 1 As shown in the figure, the principle of the detection of the disconnection sequence of the tail of the three-phase electric energy meter is as follows: during the disconnection process, when the A, B, C, and N voltage connectors in the joint junction box are disconnected, and then the two current connectors of the A, B, and C phases are short-circuited in sequence and the disconnection detection circuit board of the tail is informed, the tail disconnection detection circuit board controls the K1-K10 relays (such as Figure 1 The action shown in the figure switches the 10 groups of wires at the end of the meter (4 groups of twin-core coaxial cables for voltage lines A, B, C, and N, and 6 groups of twin-core coaxial cables for current input and output of phases A, B, and C) from the voltage and current output end (strong current end) of the joint junction box to the wiring detection end (weak current end) of the end of the meter. The 10 groups of wires are respectively connected to the 20 IO ports of the auxiliary microcontroller (defined as MCU_IO1, MCU_IO2, MCU_IO3, MC...MCU_IO20); each of the 10 IO ports of the auxiliary microcontroller is configured as one output high level, and the other IO port is configured as a pull-down input detection port. The test ports, i.e. MCU_IO1, MCU_IO3, MCU_IO5, MCU_IO7, MCU_IO9, MCU_IO11, MCU_IO13, MCU_IO15, MCU_IO17, MCU_IO19, output high level, and MCU_IO2, MCU_IO4, MCU_IO6, MCU_IO8, MCU_IO10, MCU_IO12, MCU_IO14, MCU_IO16, MCU_IO18, MCU_IO20 are configured as pull-down input detection. If the voltage line of phase A of group 1 is not removed from the end of the meter, as shown in the following example: Figure 4 As shown, MCU_IO1 and MCU_IO2 are short-circuited, and the MCU_IO2 port of the microcontroller is at a high level; Figure 6 As shown in the figure, when the A-phase voltage line is removed from the connection terminal hole 1 at the end of the meter, MCU_IO1 and MCU_IO2 are open, and the auxiliary microcontroller's MCU_IO2 port is at a low level. The order in which the meter's terminal connections are disconnected can be accurately determined by sequentially determining the low-level changes of the MCU_IO2, MCU_IO4, MCU_IO6, MCU_IO8, MCU_IO10, MCU_IO12, MCU_IO14, MCU_IO16, MCU_IO18, and MCU_IO20 ports. Conversely, the order in which the meter's terminal connections are connected can be accurately determined by sequentially determining the high-level changes of the MCU_IO2, MCU_IO4, MCU_IO6, MCU_IO8, MCU_IO10, MCU_IO12, MCU_IO14, MCU_IO16, MCU_IO18, and MCU_IO20 ports.

[0032] The method of the present invention can eliminate misjudgments and omissions during the disassembly and assembly of electric energy meters in training and assessment of electric energy metering device disassembly and assembly, help achieve fully automated scoring, and improve the fairness and impartiality of the assessment. It can also assist and guide trainees to conduct independent practice and training, while significantly reducing the workload of trainers during practical training and assessment.

Claims

1. An intelligent inspection method for three-phase electric energy meter wiring in a passive state, characterized in that: include: A meter tail disconnection detection circuit board is added between the joint junction box and the three-phase mutual inductor electric energy meter. The voltage input terminals of the three-phase electric energy meter A, B, and C phases, the neutral input terminal, and all the current connection terminals are connected to the meter tail disconnection detection circuit board through coaxial terminal blocks. The meter tail disconnection detection circuit board includes a single-chip microcomputer and a relay, and switches between strong and weak current by controlling the relay. The meter tail disconnection detection circuit board detects whether the meter tail connection is removed or installed by detecting the connection status of the two contact points on the coaxial terminal connector, and verifies whether the order of disconnecting the meter tail connection of the three-phase electric energy meter is correct; The coaxial terminal adopts a double-contact structure of a twin-core coaxial line and a plug; The coaxial terminal comprises a conductive rod (1), an end conductive tube (2), an insulating sleeve (3), a tail conductive tube (4), a locking nut (5), an insulating sleeve (6) and a double-core wire (7). One end of the conductive rod (1) serves as a plug end, and the other end passes through the end conductive tube (2) and the insulating sleeve (3) in sequence. The conductive rod (1) is in contact with the end conductive tube (2) and is connected to the end conductive tube. The tail conductive tube (4) is installed outside the insulating sleeve (3). The tail conductive tube (4) and the conductive rod (1) are in an insulated state through the insulating sleeve (3). The insulating sleeve (3) , the tail conductive tube (4) and the conductive rod (1) are locked with an insulating locking nut (5), the outer core (7-1) of the wire at one end of the double-core wire (7) is welded to the tail conductive tube (4), the inner core (7-2) of the wire is welded to the conductive rod (1), and the inner and outer cores of the other end of the double-core wire (7) are connected to the meter tail disconnection wiring detection circuit board; when testing, the connector of the coaxial terminal wire outer core (7-1) and the wire inner core (7-2) is inserted into the three-phase electric energy meter tail wiring hole and the two screws on the three-phase electric energy meter tail wiring hole are tightened. When the screws are tightened, the two contact points on the coaxial terminal block are short-circuited. When the two screws on the wiring hole at the tail of the three-phase electric energy meter are loosened and the coaxial terminal block connector is removed from the wiring hole at the tail of the three-phase electric energy meter, the two contact points on the coaxial terminal block plug are disconnected. The tail wiring removal detection circuit board detects whether the tail wiring is removed or installed by detecting the connection status of the two contact points on the coaxial terminal block plug. The contact state change state combined with the sorting algorithm determines whether the order of disconnecting the tail of the three-phase electric energy meter is correct.

2. The intelligent inspection method for three-phase electric energy meter connection in passive state according to claim 1 is characterized in that: The welding point between the inner core of the conductor (7-2) and the conductive rod (1) is wrapped with an insulating sheath (6).

3. The intelligent inspection method for three-phase electric energy meter connection in passive state according to claim 1 is characterized in that: All current connection terminals include the three-phase electricity meter A, B, and C phase current input terminals, the three-phase electricity meter A, B, and C phase current output terminals, plus the three-phase electricity meter A, B, and C phase voltage input terminals and neutral input terminals, a total of 10 groups of terminal blocks are connected to the meter tail disconnection detection circuit board through coaxial terminal blocks.

4. The intelligent inspection method for three-phase electric energy meter connection in passive state according to claim 1 is characterized in that: One end of the double-core conductor (7) away from the conductive rod (1) can also be connected to a virtual load power supply.

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