On-site verification device for electric energy meter

Abstract

The invention relates to the technical field of verification equipment, in particular to an electric energy meter on-site verification device, which comprises a load unit comprising a shell; the mounting surface of the shell is provided with a probe unit, and the probe unit comprises a plurality of telescopic probes; a locking buckle and a locking buckle release switch are arranged on each of the two sides of the mounting surface of the shell, and the locking buckle release switches are in driving connection with the locking buckles and are used for driving the locking buckles to be clamped with clamping grooves in the two sides of the to-be-verified electric energy meter; a virtual load module and a real load module are arranged in the shell, the virtual load module and the real load module are respectively connected to one end of the change-over switch, and the other end of the change-over switch is connected with the probe unit; the shell is provided with an output port which is connected with the virtual load module and the real load module, and the technical problems that an existing electric energy meter verification device is single in function and tedious in use are solved.

Description

Technical Field

[0001] This invention relates to the field of verification equipment technology, and in particular to an on-site verification device for electrical energy meters. Background Technology

[0002] An electricity meter is a measuring instrument used to measure and record the energy consumption of electricity. The accuracy and effectiveness of its measurement affect power system dispatching, energy calculation, and energy monitoring. Therefore, in order to reduce the occurrence of inaccurate measurement during the operation of electricity meters, existing technologies typically perform on-site calibration of electricity meters after they are put into operation.

[0003] Currently, there are two methods for on-site verification of electricity meters. One is to remove the meter and send it to a professional testing laboratory for metering testing. However, removing and installing the meter requires disconnecting the main power switch from the user's circuit breaker, and this process is time-consuming and labor-intensive. The meter also takes at least 4-5 days to be retrieved and sent for testing, resulting in a long cycle and significant inconvenience for users. The second method involves professional technicians bringing specialized on-site testing equipment. However, often, technicians can only perform the test when the user has electricity. When the user is not using electricity, the meter cannot register readings, making testing impossible. Traditional on-site testing uses clamp meters to measure the circuit current, requiring three or more clamp meters, which is inconvenient to carry. Figure 1 As shown, this type of test requires multiple clamps to be attached to the voltage terminals of the meter for voltage connection. This wiring is cumbersome, and this method typically involves live operation by technicians. Since the voltage being tested is usually 220VAC or 380VAC, the operation is highly dangerous. Furthermore, the live clamps are prone to slippage, potentially leading to short circuits or electric shocks. Existing calibration devices usually only have a single function of virtual load testing, and connection requires screws and tools such as screwdrivers, making the process cumbersome. Therefore, it is necessary to propose a new on-site calibration device for electricity meters. Summary of the Invention

[0004] This invention provides an on-site verification device for electricity meters, which solves the technical problems of existing electricity meter verification devices having limited functionality and being cumbersome to use.

[0005] The present invention provides an on-site verification device for an energy meter, comprising: a load unit, the load unit including a housing; a probe unit provided on the mounting surface of the housing, the probe unit including a plurality of retractable probes; and locking buckles and locking buckle release switches provided on both sides of the mounting surface of the housing, the locking buckle release switches being connected to the locking buckle drive and used to drive the locking buckles to engage with the slots on both sides of the energy meter to be verified.

[0006] The housing is equipped with a virtual load module and a real load module. The virtual load module and the real load module are respectively connected to one end of a switch, and the other end of the switch is connected to the probe unit. The housing is provided with an output port, which is connected to the virtual load module and the real load module respectively.

[0007] Optionally, the virtual load module includes: a current boosting unit module;

[0008] One side of the current boosting unit module is connected to the current amplitude regulator, and one end of the other side of the current boosting unit module is connected to the switching switch; the other end of the other side of the current boosting unit module is connected to the probe unit.

[0009] The current amplitude regulator is connected to the power factor adjustment module.

[0010] Optionally, the actual load module includes: a resistor assembly; one end of the resistor assembly is connected to a switching switch; and the other end of the resistor assembly is connected to the probe unit.

[0011] Optionally, it may also include: a power supply module;

[0012] The input terminal of the power supply module is connected to the power source;

[0013] The output terminal of the power supply module is connected to the power factor adjustment module, the other end of the switching switch, and the connection point between the actual load module and the probe unit.

[0014] Optionally, it further includes: a protection module; the protection module includes a short-circuit protection relay;

[0015] The normally closed contact of the short-circuit protection relay is connected to the connection point between the other end of the current boosting unit module and the probe unit.

[0016] The coil of the short-circuit protection relay is connected to one end of the short-circuit detection unit;

[0017] The other end of the short-circuit detection unit is connected to the other end of the switching switch, the connection between the normally closed contact of the anti-short-circuit relay and the probe unit, and the other end of the resistor assembly.

[0018] Optionally, the probe unit is provided with multiple direct-access voltage probes, multiple transformer-access voltage probes, and multiple current probes.

[0019] Optionally, a heat dissipation hole is provided on one side of the housing;

[0020] The housing is equipped with heat dissipation elements at the positions corresponding to the heat dissipation holes.

[0021] Optionally, it also includes a verification unit;

[0022] The verification unit is connected to the output port of the load unit.

[0023] Optionally, the verification unit includes an input port, an analog-to-digital converter, and a main control unit;

[0024] One end of the input port is connected to the output port of the load unit;

[0025] The other end of the input port is connected to one end of the analog-to-digital converter;

[0026] The other end of the analog-to-digital converter is connected to the main control unit.

[0027] Optionally, the verification unit further includes a temperature and humidity detection element;

[0028] The temperature and humidity detection element is connected to the main control unit.

[0029] As can be seen from the above technical solutions, the present invention has the following advantages:

[0030] This invention provides an on-site verification device for an energy meter, comprising: a load unit, the load unit including a housing; a probe unit including multiple retractable probes disposed on the mounting surface of the housing; locking latches and locking latch release switches disposed on both sides of the mounting surface of the housing, the locking latch release switches being driven by the locking latches to drive the locking latches to engage with the slots on both sides of the energy meter to be verified; a virtual load module and a real load module disposed inside the housing, the virtual load module and the real load module being respectively connected to one end of a switching switch, the other end of the switching switch being connected to the probe unit; and an output port disposed on the housing, which is respectively connected to the virtual load module and the real load module.

[0031] In this invention, a probe unit comprising multiple retractable probes is provided on the mounting surface of the housing. Locking latches and locking latch release switches are located on both sides of the mounting surface. During calibration, the locking latches are engaged with the energy meter under calibration via the locking latch release switches. This causes the probes on the mounting surface to press against the terminals of the energy meter under calibration, allowing the energy meter to connect to the virtual load module and the real load module inside the housing via the probes. Therefore, this invention requires only a single press-to-connection, avoiding the cumbersome wiring and unsafe operation issues associated with manual live-line clamps in existing solutions. This significantly improves operational safety and convenience. Furthermore, the locking latches and locking latch release switches ensure stable fixation of the load unit to the energy meter under calibration. The connection improves both stability and convenience of fixed connections. Furthermore, the load unit of this invention includes a virtual load module and a real load module, along with a switching switch connecting them. During actual verification, the switching switch selects one load module to calibrate the energy meter under test. When switched to the virtual load module, a calibration current is generated to calibrate the energy meter, avoiding the inability to complete calibration when the user is not using electricity, as is common in existing technologies. When switched to the real load module, the voltage and current of the energy meter are collected, providing effective data support for checking the wiring of the energy meter under test. Therefore, the energy meter on-site calibration device provided by this invention, by incorporating both virtual and real load modules, avoids the limitation of existing technologies that require user power consumption for testing, making testing more flexible and convenient. It also allows for wiring checks of the energy meter, avoiding the single-function limitations of traditional calibration devices. Therefore, the on-site verification device for electricity meters provided by the present invention solves the technical problems of existing electricity meter verification devices having limited functions and being cumbersome to use. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 Wiring diagram of the existing verification device;

[0034] Figure 2 This is one of the structural schematic diagrams of an on-site verification device for electrical energy meters provided in an embodiment of the present invention;

[0035] Figure 3 This is a second schematic diagram of the structure of an on-site verification device for an electrical energy meter provided in an embodiment of the present invention;

[0036] Figure 4 This is the third schematic diagram of the structure of an on-site verification device for an electrical energy meter provided in an embodiment of the present invention;

[0037] Figure 5 This is the fourth schematic diagram of a field verification device for an electrical energy meter provided in an embodiment of the present invention;

[0038] Figure 6 This is the fifth schematic diagram of the structure of an on-site verification device for an electrical energy meter provided in an embodiment of the present invention;

[0039] Figure 7 This is the sixth schematic diagram of the structure of an on-site verification device for an electrical energy meter provided in an embodiment of the present invention;

[0040] Figure 8 This is the seventh schematic diagram of the structure of an on-site verification device for an electrical energy meter provided in an embodiment of the present invention;

[0041] Figure 9 This is a schematic diagram illustrating the principles of the virtual load module and the real load module provided in an embodiment of the present invention.

[0042] Figure 10 This is a block diagram of the architecture of the verification unit provided in an embodiment of the present invention;

[0043] In the diagram, 1. Locking buckle; 2. Direct-connect voltage probe; 3. Transformer-connected voltage probe; 4. Current probe; 5. Locking buckle release switch; 6. Auxiliary terminal probe; 7. Three-phase virtual load transformer; 8. Cooling fan; 9. Output port. Detailed Implementation

[0044] The present invention provides an on-site verification device for electricity meters, which solves the technical problems of existing electricity meter verification devices having limited functions and being cumbersome to use.

[0045] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0046] Please see Figures 2 to 8The present invention provides an on-site verification device for an energy meter, comprising: a load unit, the load unit including a housing; a probe unit provided on the mounting surface of the housing, the probe unit including a plurality of retractable probes; a locking buckle 1 and a locking buckle release switch 5 provided on both sides of the mounting surface of the housing, the locking buckle release switch 5 being drivenly connected to the locking buckle 1, for driving the locking buckle 1 to engage with the slots on both sides of the energy meter to be verified;

[0047] The housing is equipped with a virtual load module and a real load module. The virtual load module and the real load module are respectively connected to one end of a switch, and the other end of the switch is connected to the probe unit. The housing is provided with an output port 9, which is connected to the virtual load module and the real load module respectively.

[0048] It should be noted that the shell is made of ABS (acrylonitrile-butadiene-styrene copolymer), which has the advantages of being lightweight, having good insulation, high mechanical strength, and good durability.

[0049] The locking buckle 1 and the locking buckle release switch 5 adopt the driving principle of a spring-loaded buckle. In actual use, by pressing the locking buckle release switch 5, the spring inside the locking buckle release switch 5 is compressed, thereby moving the locking buckle 1 so that the locking buckle 1 can be engaged in the slot of the energy meter to be tested. After releasing the locking buckle release switch 5, the spring inside the locking buckle release switch 5 returns to its original position, driving the locking buckle 1 to return to its original position. Thus, the locking buckle 1 remains in the open state and is fixedly engaged with the slot under the action of the spring. Therefore, the load unit can be quickly wired to the energy meter to be tested. After the test is completed, by simultaneously pressing the locking buckle release switches 5 on both sides of the mounting surface, the locking buckle 1 is driven to disengage from the slot, thereby removing the load unit from the energy meter to be tested. Therefore, the spring-loaded clip-on fixing method allows for automatic connection of voltage and current lines simply by pressing, achieving one-button operation. This not only avoids the risks associated with traditional voltage clips operating under live conditions, but also provides convenient operation, structural stability, and eliminates the cumbersome process of using external screwdrivers and other tools for screw fixing found in existing calibration devices. It is understood that the slot of the energy meter to be calibrated can be matched to the shape of the locking clip 1 to ensure proper engagement.

[0050] The virtual load module has three virtual current loads. Its working principle is to simulate the impedance, power factor, active / reactive power, and other parameters of a real load, outputting a pre-set analog electrical signal to the energy meter to simulate load characteristics and generate metering pulses. The real load module has three actual load units, and the probe unit has four voltage crimping devices to automatically connect the four-phase voltage lines. Therefore, this embodiment achieves automatic connection of both virtual and actual loads, solving the problem of not being able to detect when the user is not using electricity. It also functions as a virtual load, allowing for detection when the user is not using electricity. Furthermore, by setting up the real load module, the load units can be combined with a field calibrator to perform on-site wiring checks, overcoming the limitations of a single virtual load module in terms of limited functionality and application scenarios. It is understood that the positions of the probes in the probe unit are matched to the meter positions of the three-phase energy meter.

[0051] The virtual load module and the real load module are switched between two modes using a switch. When switched to the virtual load module, the load unit operates in virtual load mode. After the three-phase current is connected, the virtual load module is turned on and outputs a preset analog electrical signal to the energy meter. This allows the meter to flow current even when there is no external power supply, thereby generating a measured pulse. This pulse is then transmitted to the calibration unit, which compares the measured pulse with a standard energy pulse to calculate the error of the measured energy meter, thus achieving the purpose of calibrating the energy meter.

[0052] The real-load module is used in scenarios where users are using electricity normally and there is electrical flow on the electricity meter. When switching to the real-load module, it connects to the electricity meter under test, allowing the electricity from the meter to flow through the module. Therefore, by collecting current and voltage data passing through the real-load module, analysis is performed to determine if the three-phase wiring of the meter under test is incorrect. It is understood that the voltage and current in the standard wiring of the meter under test have a fixed phase relationship. By comparing the phase relationship of the measured current and voltage data from the meter under test with the corresponding phase relationship in the standard wiring, it is possible to determine if a wiring error exists. Therefore, this device, by using a real-load module, can assist in wiring verification, thus avoiding the shortcomings of a single virtual load being insufficient for wiring verification.

[0053] In this invention, a probe unit comprising multiple retractable probes is provided on the mounting surface of the housing. Locking latches 1 and locking latch release switches 5 are provided on both sides of the mounting surface. During verification, the locking latches 1 are engaged with the energy meter to be verified via the locking latch release switches 5. This causes the probes on the mounting surface to press against the terminals of the energy meter, allowing the energy meter to connect to the virtual load module and the real load module inside the housing via the probes. Therefore, this invention requires only a single press-to-connection, avoiding the cumbersome wiring and unsafe operation problems associated with manual live-line clamps in existing solutions. This significantly improves operational safety and convenience. Furthermore, the locking latches 1 and 5 ensure stable connection between the load unit and the energy meter to be verified. The fixed connection improves both stability and convenience. Furthermore, the load unit of this invention includes a virtual load module and a real load module, with a switching switch connecting them. During actual verification, the switch selects one load module to calibrate the energy meter under test. When switched to the virtual load module, a calibration current is generated to calibrate the energy meter, avoiding the inability to complete calibration when the user is not using electricity, as is common in existing technologies. When switched to the real load module, the voltage and current of the energy meter are collected, providing effective data support for checking the wiring of the energy meter. Therefore, this invention provides an on-site energy meter calibration device that, by incorporating both virtual and real load modules, avoids the limitation of existing technologies that require user power consumption for testing, making testing more flexible and convenient. It also allows for wiring checks of the energy meter, avoiding the single-function limitations of traditional calibration devices. Therefore, the on-site verification device for electricity meters provided by the present invention solves the technical problems of existing electricity meter verification devices having limited functions and being cumbersome to use.

[0054] In one embodiment, the probe unit is provided with multiple direct-access voltage probes 2, multiple transformer-access voltage probes 3, and multiple current probes 4.

[0055] It should be noted that in this embodiment, multiple direct-access voltage probes 2 are arranged on the surface of the housing according to the layout of the voltage terminals of the direct-access three-phase energy meter. Thus, when the direct-access three-phase energy meter needs to be calibrated, after the load unit is connected to the energy meter, the direct-access voltage probes 2 can be pressed against the voltage terminals of the direct-access three-phase energy meter to complete the connection, so as to collect and transmit the voltage of the energy meter to be calibrated to the calibration unit, thereby realizing automatic voltage connection and detection.

[0056] Multiple transformer-connected voltage probes 3 are positioned on the surface of the housing according to the layout of the voltage terminals of the transformer-connected three-phase energy meter. When the transformer-connected three-phase energy meter needs to be calibrated, after the load unit is connected to the energy meter, the transformer-connected voltage probes 3 can be pressed against the voltage terminals of the transformer-connected three-phase energy meter to complete the connection, so as to collect and transmit the voltage of the energy meter to be calibrated to the calibration unit, thereby realizing automatic voltage connection and detection.

[0057] There are 6 current probes 4. After the load unit is connected to the three-phase energy meter, the 6 current probes 4 are automatically connected to the A+, A-, B+, B-, C+, and C- terminals of the energy meter to be tested.

[0058] It is understandable that the direct-connection voltage probe 2, the transformer-connection voltage probe 3, and the current probe 4 have the same structure. They all have a spring structure inside to achieve a retractable function, so that each probe can automatically connect to the terminal of the energy meter to realize the transmission of current and voltage.

[0059] In one embodiment, the probe unit further includes an auxiliary terminal probe 6.

[0060] In one embodiment, the virtual load module includes: a current boosting unit module;

[0061] One side of the current boosting unit module is connected to the current amplitude regulator, and one end of the other side of the current boosting unit module is connected to the switching switch; the other end of the other side of the current boosting unit module is connected to the probe unit.

[0062] The current amplitude regulator is connected to the power factor adjustment module.

[0063] It should be noted that the current boosting unit module includes a three-phase virtual load transformer 7, which is a three-phase current transformer, meaning that a current transformer is set for each phase.

[0064] In one embodiment, the actual load module includes: a resistor assembly; one end of the resistor assembly is connected to a switching switch; and the other end of the resistor assembly is connected to the probe unit.

[0065] In one embodiment, it further includes: a power supply module;

[0066] The input terminal of the power supply module is connected to the power source;

[0067] The output terminal of the power supply module is connected to the power factor adjustment module, the other end of the switching switch, and the connection point between the actual load module and the probe unit.

[0068] In one embodiment, it further includes: a protection module; the protection module includes a short-circuit protection relay;

[0069] The normally closed contact of the short-circuit protection relay is connected to the connection point between the other end of the current boosting unit module and the probe unit.

[0070] The coil of the short-circuit protection relay is connected to one end of the short-circuit detection unit;

[0071] The other end of the short-circuit detection unit is connected to the other end of the switching switch, the connection between the normally closed contact of the anti-short-circuit relay and the probe unit, and the other end of the resistor assembly.

[0072] It should be noted that, as Figure 9 As shown, the working principle of the virtual load module and the real load module in this device will be explained below, taking single-phase detection as an example. Figure 9 In this invention, the virtual / real load switching switch is the switching switch itself; the real load is the actual load, and the virtual load is the virtual load; the miswiring detection module is the protection module itself. To facilitate illustrating the connection relationship between the virtual and real loads, Figure 9 The diagram uses red, yellow, and black wires to illustrate the wiring. It can be understood that in actual applications, this wiring is implemented through a probe unit.

[0073] like Figure 9 As shown, when the virtual load switching switch is switched to the virtual load side, the virtual load operates. The virtual load is implemented by the current boosting unit module. The current boosting unit module adopts a transformation ratio of 1143:4. Based on the law of conservation of energy, the primary current value of the current boosting unit module is adjusted by regulating the size of the downstream regulating resistor, and then the secondary current is regulated by the correlation principle of the current transformer. The power factor adjustment module has selectable ranges, which can be used to select capacitive, inductive, and resistive loads to achieve different power factors. This allows the current boosting unit module to output the corresponding power factor electrical signal to the energy meter for verification.

[0074] Figure 9 The internal circuitry uses an online power supply module to power relays and logic circuits.

[0075] like Figure 9As shown, the normally closed contact of the short-circuit protection relay is in the open state. However, in actual use, the normally closed contact of the short-circuit protection relay is in the closed state. The short-circuit judgment unit collects the inter-line voltage and judges whether there is a short circuit based on the inter-line voltage. If so, it outputs an electrical signal to drive the transistor to cut off, so that the circuit where the coil of the short-circuit protection relay is located is turned on, thereby de-energizing the coil of the short-circuit protection relay, opening the normally closed contact of the short-circuit relay, and thus disconnecting the device from the energy meter.

[0076] When switched to the actual load mode, the actual load uses a structure of 2kΩ nickel-chromium alloy power resistors with heat sinks for each circuit, which can generate a current of about 0.11A in each circuit. At the same time, the load power is 24.2W / phase, and the total power of the three phases is 72.6W.

[0077] In one embodiment, a heat dissipation hole is provided on one side of the housing;

[0078] The housing is equipped with heat dissipation elements at the positions corresponding to the heat dissipation holes.

[0079] It should be noted that when switching to the actual load module, since the actual load module generates heat during operation, this embodiment uses heat dissipation elements inside the housing to reduce the risk of overheating and burning out of the actual load module. In one example, a 60mm ultra-thin cooling fan 8 with an airflow of 18 CFM can be used to achieve effective heat dissipation.

[0080] In one embodiment, a verification unit is also included;

[0081] The verification unit is connected to the output port 9 of the load unit.

[0082] In one embodiment, the verification unit includes an input port, an analog-to-digital converter, and a main control unit;

[0083] One end of the input port is connected to the output port 9 of the load unit;

[0084] The other end of the input port is connected to one end of the analog-to-digital converter;

[0085] The other end of the analog-to-digital converter is connected to the main control unit.

[0086] In one embodiment, the verification unit further includes a temperature and humidity detection element;

[0087] The temperature and humidity detection element is connected to the main control unit.

[0088] It should be noted that the verification unit in this embodiment adopts the STM32 chip architecture, and is composed of a three-phase voltage and current metering and detection unit, an LCD touch display unit, a pulse input unit, an RS485 communication unit, an EEPROM storage unit, etc.

[0089] Specifically, the verification unit includes: MCU (i.e., main control unit), U / I input port, analog-to-digital converter, temperature and humidity detection element, pulse input / output port 9, RS232 / RS485 / USB communication interface, EEPROM storage unit, LCD touch screen, MAX6225 voltage reference chip, MAX308CMOS analog multiplexer, and LM1117 voltage regulator.

[0090] like Figure 10 As shown, the MCU uses the STM32F429 platform, which can realize functions such as voltage signal acquisition, current signal acquisition and calculation, LCD touch screen signal reading and control, RS485 communication, data storage, and reading of temperature and humidity sensor signals. It can realize functions such as three-phase voltage measurement, three-phase current measurement, three-phase power and energy measurement, phase measurement, wiring error identification, and energy pulse input.

[0091] The temperature and humidity detection element uses a temperature and humidity sensor, a dedicated device for on-site environmental data acquisition. It records temperature and humidity data at the testing site, providing environmental parameter data for testing or measurement traceability. In one example, the temperature and humidity sensor used is the HDC1080DMBR model, with a temperature acquisition range of -40℃ to +125℃ and a humidity acquisition range of 0%RH to 100%RH, which meets the needs of this on-site testing. In one example, the temperature and humidity sensor is connected to the MCU via an I2C interface.

[0092] Pulse input / output port 9 is used to implement the pulse input acquisition function. The pulse input acquisition function collects the pulse data of the energy meter to be calibrated, inputs it to the energy meter field calibrator, compares the standard pulse converted from the standard power data measured by the field calibrator with the pulse being measured, and calculates the error data of the energy meter to be calibrated through the MCU.

[0093] The RS232 / RS485 / USB communication interface includes one RS485 communication interface, one RS232 communication interface, and one USB communication interface. The RS485 communication interface is primarily used to communicate with the energy meter under test. The calibrator's built-in 597 and 687 communication protocols allow for the reading of data parameters from the smart energy meter, facilitating better recording of meter information. The RS232 communication interface is the uplink communication interface, enabling connection between the field calibrator and PC software for data transmission and control. The USB interface is used for program upgrades and output / export. When a program upgrade is needed, inserting a USB flash drive containing the upgrade program will automatically perform the upgrade. Users can also choose to export the tested meter data for convenient report generation.

[0094] An EEPROM storage unit is a storage chip used to save settings parameters. In one example, the EEPROM storage unit can be an M24256-BRMN6TP storage chip with a storage capacity of 256K, used to store device parameters and user-defined status data.

[0095] The LCD touchscreen uses a capacitive touchscreen, supporting not only testing interfaces, wiring inspection interfaces, test data display interfaces, calibration interfaces, and settings interfaces, but also touch-based data input functionality. It allows users to perform touch operations such as entering information about the energy meter to be calibrated, selecting testing schemes, choosing test points, starting and ending experiments, and saving data. This reduces the number of physical buttons found in traditional field calibrators, making the device smaller and more convenient to operate.

[0096] The load unit inputs the analog voltage, current, and other parameters measured by the energy meter under test through the U / I input port to a 24-bit low-noise, high-speed analog-to-digital converter (ADC). The ADC converts the acquired three-phase voltage and current data into digital signals and transmits them to the MCU chip. In one example, the ADC used is the LTC2380-24, which has an integrated digital filter with real-time averaging function and a typical integral nonlinearity (INL) of ≤±0.5ppm, which can meet the signal acquisition and conversion requirements of a 0.05-level field calibrator. This is understandable. Figure 10 The snap-on intelligent virtual and real load unit in the present invention is the load unit of the present invention.

[0097] In summary, the on-site energy meter verification device provided by this invention adopts a spring-loaded snap-fit ​​installation, allowing for automatic connection of voltage, current, and auxiliary terminals of the meter with a single press, eliminating the need for manual operation with live voltage clamps and greatly improving operational safety. Simultaneously, it avoids the difficulties of using clamp meters to carry current, effectively improving wiring efficiency. Furthermore, this innovative spring-loaded snap-fit ​​fixing structure avoids the cumbersome operation of fixing virtual loads with screwdrivers and other tools required by some existing market offerings. The on-site energy meter verification device provided by this invention employs a virtual and real load compatible design, effectively avoiding the dilemma of traditional methods requiring users to use electricity for testing, making testing more flexible and convenient. It also solves the problem of existing virtual loads on the market having only one function—providing current but not wiring checks. This invention uses a real and virtual load switching scheme. The virtual load satisfies the function of generating current when the user is not using electricity, while the real load addresses the shortcoming of virtual loads being unable to perform wiring checks. At the same time, the switching design can meet the needs of multiple usage scenarios and avoids the problem of continuous heat generation when the real load is constantly loaded.

[0098] It should be noted that in the description of this invention, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0099] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0100] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electric energy meter field calibration device, characterized in that, The utility model relates to a kind of electric energy meter verification device, including: Load unit, the load unit includes shell;The mounting surface of the shell is provided with probe unit, the probe unit includes a plurality of retractable probe;The mounting surface of the shell is provided with locking buckle and locking buckle release switch on both sides, and the locking buckle release switch is driven connection with locking buckle, for driving the locking buckle and the card slot of the electric energy meter to be verified two sides card joint; The inside of the shell is provided with virtual load module and real load module, and the virtual load module and the real load module are respectively connected to one end of switch, and the other end of the switch is connected with the probe unit;The shell is provided with output port, and is connected with the virtual load module and real load module respectively.

2. The apparatus of claim 1, wherein, The virtual load module includes: current rise unit module; One side of the current rise unit module is connected with current amplitude regulator, and the other end of the other side of the current rise unit module is connected with the switch;The other end of the other side of the current rise unit module is connected with the probe unit; The current amplitude regulator is connected with power factor adjustment module.

3. The apparatus of claim 2, wherein, The real load module includes: resistance component;One end of the resistance component is connected with switch;The other end of the resistance component is connected with the probe unit.

4. The apparatus of claim 3, wherein, Further including: Power taking module; The input end of the power taking module is connected with power supply; The output end of the power taking module is connected to the power factor adjustment module, the other end of the switch, the connection place of the real load module and the probe unit respectively.

5. The apparatus of claim 4, wherein, Further including: Protection module;The protection module includes anti-short-circuit relay; The normally closed contact of the anti-short-circuit relay is connected between the other end of the other side of the current rise unit module and the probe unit; The coil of the anti-short-circuit relay is connected with one end of short-circuit judging unit; The other end of the short-circuit judging unit is connected with the other end of the switch, the connection place between the normally closed contact of the anti-short-circuit relay and the probe unit, the other end of the resistance component respectively.

6. The apparatus of claim 5, wherein, The probe unit is provided with a plurality of direct access type voltage probes, a plurality of mutual inductor access type voltage probes and a plurality of current probes.

7. The apparatus of claim 6, wherein, The side surface of the shell is provided with heat dissipation hole; The inside of the shell is provided with heat dissipation element corresponding to the position of the heat dissipation hole.

8. The apparatus of claim 7, wherein, Further including verification unit; The output port of the load unit is connected with the verification unit.

9. The apparatus of claim 8, wherein, The verification unit includes input port, analog-digital converter and main control unit; One end of the input port is connected with the output port of the load unit; The other end of the input port is connected with one end of the analog-digital converter; The other end of the analog-digital converter is connected with the main control unit.

10. The apparatus of claim 9, wherein, The verification unit further includes temperature and humidity detection element; The temperature and humidity detection element is connected with the main control unit.

Images