CN213023537U - Installation type standard meter with pulse input and output switching function - Google Patents
Installation type standard meter with pulse input and output switching function Download PDFInfo
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- CN213023537U CN213023537U CN202020753740.3U CN202020753740U CN213023537U CN 213023537 U CN213023537 U CN 213023537U CN 202020753740 U CN202020753740 U CN 202020753740U CN 213023537 U CN213023537 U CN 213023537U
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Abstract
The utility model discloses an installation formula standard table with pulse input/output switches function, installation formula standard table includes voltage sampling circuit, current sampling circuit, voltage channel ADC converter, current channel ADC converter, RS485 communication interface, DSP data processing unit, pulse switching unit, pulse terminal and wireless transceiver module. The utility model discloses the pulse terminal of well installation formula standard meter both can make output terminal also can make input terminal wiring by the school electric energy meter, and conventional installation formula standard meter, pulse terminal only do active pulse, idle pulse output terminal and use. The utility model discloses when well pulse terminal used as active pulse, idle pulse input terminal, it was continuous with the pulse terminal of installation formula standard table by the active, idle pulse of school's electric energy meter. When the RS485 communication port of the installation type standard meter or the electric energy meter to be calibrated fails, electric energy can be metered through the pulse input terminal, so that the error of the electric energy meter to be calibrated is measured in multiple calibration modes, and the calibration efficiency is improved.
Description
Technical Field
The utility model relates to an electric energy measurement technical field, especially an installation formula standard meter with pulse input/output switches function.
Background
The installation type standard electric energy meter (hereinafter referred to as installation type standard meter) is an electric energy meter which not only meets the appearance and the size of the installation type electric energy meter, but also has the high-precision characteristic of the standard electric energy meter. With the development of the smart grid, the installation type standard electric energy meter plays an increasingly important role in monitoring the operation quality of the automatic electric energy meter verification system, can be fixed on a certain station of the verification system for quality monitoring, and can be circulated in each bin and station of the verification system like the installation type electric energy meter to be detected, so that the dynamic monitoring of the verification system is realized.
Because the pulse terminal of the conventional installation type standard meter is only used as an output terminal and cannot be used as a pulse input terminal, when the RS485 port of the installation type standard meter or the calibrated electric energy meter fails, calibration data cannot be copied, and the calibration efficiency of the calibrated electric energy meter is influenced.
For overcoming the not enough of prior art, the utility model provides a high accuracy installation formula standard meter, the pulse terminal of this installation formula standard meter both can regard as active pulse, idle pulse output terminal, also can regard as input terminal wiring by the active pulse, the idle pulse of school's electric energy meter, carry out the electric energy measurement through calculating the active pulse, the idle pulse of being checked the electric energy meter, compare with the electric energy of installation formula standard meter self measurement to the measurement is by the electric energy error of school's electric energy meter. The technology is different from the traditional mode of copying the electric energy meter to be calibrated by the RS485, namely, when the RS485 port fails, the calibration work of the electric energy meter to be calibrated can still be normally finished, so that the calibration efficiency is improved.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome prior art's not enough, provide an installation formula standard table with pulse input/output switches function to solve the problem that proposes in the above-mentioned technical background.
In order to achieve the above object, the present invention provides a method for manufacturing a semiconductor device, comprising:
an installation type standard meter with a pulse input and output switching function comprises a voltage sampling circuit, a current sampling circuit, a voltage channel ADC (analog to digital converter), a current channel ADC, a DSP (digital signal processor) data processing unit, an RS485 communication interface, a pulse switching unit, two current isolation modules, a pulse terminal and a wireless transceiving module, wherein the voltage sampling circuit is connected with the DSP data processing unit through the voltage channel ADC; the current sampling circuit is connected with the DSP data processing unit through the current channel ADC, the DSP data processing unit is further respectively electrically connected with the pulse switching unit, the wireless transceiver module and the RS485 communication interface, and the pulse switching unit is electrically connected with the pulse terminal through the two current isolation modules.
In the technical scheme, the liquid crystal display device further comprises a liquid crystal screen, and the liquid crystal screen is electrically connected with the DSP data processing unit.
In the above technical solution, the DSP data processing unit employs a chip TMS320F 28377.
In the above technical solution, the pulse switching unit adopts a chip 74LVX 3245.
In the above technical solution, each of the galvanic isolation modules includes a chip ISO7421, the chip ISO7421 has two isolation channels, each isolation channel has a logic input and output buffer, and each isolation channel is connected in series with the chip 74LVX3245 through a current limiting resistor.
In the technical scheme, the accuracy grade of the installation type standard meter is 0.02 grade.
Among the above-mentioned technical scheme, still include the host computer, the host computer is connected with DSP data processing unit communication, is used for receiving the data that installation formula standard meter detected and control DSP data processing unit sets up pulse terminal output active pulse, reactive pulse, perhaps sets up the active pulse, the reactive pulse of pulse terminal input surveyed the electric energy meter.
Compared with the prior art, the beneficial effects of the utility model are that:
the utility model discloses in, the pulse terminal of installation formula standard meter both can regard as active pulse, reactive pulse output terminal also can regard as input terminal wiring by the active pulse, the reactive pulse of school's electric energy meter, and the installation formula standard meter carries out the electric energy measurement back through receiving and calculating by the active pulse, the reactive pulse of school's electric energy meter, compares with the electric energy of installation formula standard meter self measurement to measure the error by the electric energy meter of school. The utility model provides a measure by new examination mode of school's electric energy meter error for by school's electric energy meter examination more diversified.
Drawings
FIG. 1 is a schematic block diagram of the present invention;
FIG. 2 is a schematic block diagram of the mid-mounted standard meter according to the present invention for switching the input and output of pulses;
FIG. 3 is a diagram of the working mode of the pulse terminal of the installation type standard meter for outputting active pulse and reactive pulse; the solid line is used for controlling the pulse terminal to output active pulses by the DSP data processing unit, and the dotted line is used for controlling the pulse terminal to output reactive pulses by the DSP data processing unit;
FIG. 4 is a diagram of the working mode of inputting the active pulse and the reactive pulse of the electric energy meter to be tested into the pulse terminal of the installation type standard meter; the solid line is an active pulse input into the detected electric energy meter by the DSP data processing unit control pulse terminal, and the dotted line is a reactive pulse input into the detected electric energy meter by the DSP data processing unit control pulse terminal;
in the figure, 1, a voltage sampling circuit; 2. a current sampling circuit; 3. a voltage channel ADC converter; 4. a current channel ADC converter; 5. a DSP data processing unit; 6. an RS485 communication interface; 7. a pulse switching unit; 8. a galvanic isolation module; 9. a pulse terminal; 10. a wireless transceiver module; 11. a liquid crystal panel.
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can also be implemented or applied through other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict.
It should be noted that the drawings provided in the following embodiments are only for illustrating the basic concept of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the form, amount and ratio of the components in actual implementation may be changed at will, and the layout of the components may be more complicated.
Referring to fig. 1 to 4, the utility model provides an installation formula standard table, including a voltage sampling circuit 1, a current sampling circuit 2, a voltage channel ADC converter 3, a current channel ADC converter 4, a DSP data processing unit 5, a RS485 communication interface 6, a pulse switching unit 7, two galvanic isolation modules 8, a pulse terminal 9 and a wireless transceiver module 10, voltage sampling circuit 1 passes through voltage channel ADC converter 3 and is connected with DSP data processing unit 5, and current sampling circuit 2 passes through current channel ADC converter 4 and is connected with DSP data processing unit 5, DSP data processing unit 5 still respectively with pulse switching unit 7, wireless transceiver module 10 and RS485 communication interface 6 electricity be connected, pulse switching unit 7 is connected with pulse terminal 9 electricity through two galvanic isolation modules 8.
The utility model discloses in, still include LCD screen 11, LCD screen 11 is connected with 5 electricity of DSP data processing unit. The liquid crystal screen 11 displays parameters such as voltage value, current value, power value and the like calculated by the DSP data processing unit 5 on the liquid crystal screen, and related parameter information of the installation type standard table can be intuitively known.
The utility model discloses in, voltage sampling circuit 1 is through resistance partial pressure sampling conversion to the small signal with voltage, sends into voltage channel ADC converter 3.
The current sampling circuit 2 converts the current into a small current through a current transformer, converts the small current into a voltage signal through a sampling resistor, and sends the voltage signal to the current channel ADC converter 4.
The voltage channel ADC converter 3 performs analog-to-digital conversion on the voltage signal sent by the voltage sampling, converts the voltage signal into a voltage digital signal, and sends the voltage digital signal to the DSP data processing unit 5.
The current channel ADC converter 4 performs analog-to-digital conversion on the current signal sampled and sent by the current sampling, converts the current signal into a current digital signal, and sends the current digital signal to the DSP data processing unit 5.
The DSP data processing unit 5 is used for calculating a voltage signal converted by the voltage channel ADC 3 and a current signal converted by the current channel ADC 4 to obtain an actual power value, and the DSP data processing unit is also used for measuring the phase, the frequency and the like of a true effective value of the voltage and the current; the device is also used for controlling the input or output of a pulse terminal, measuring the active pulse and the reactive pulse of the received electric energy meter when the pulse terminal is input, comparing the measured electric energy parameters with the electric energy parameters measured by the installation type standard meter, and calculating the error precision of the electric energy meter to be corrected;
and the pulse switching unit 7 is used for receiving a command sent by the DSP data processing unit 5 for switching input or output of the pulse terminal, and setting the switching pulse terminal 9 as an active pulse output terminal, a reactive pulse output terminal, an active pulse input terminal and a reactive pulse input terminal.
The pulse terminal 9 is used for leading out terminals for inputting and outputting active pulses or leading out terminals for inputting and outputting reactive pulses, and wiring is convenient.
The RS485 communication interface 6 is realized by a 485 chip in the installation type standard meter, and the RS485 communication mode is realized by using the 485 chip.
In a further embodiment, the DSP data processing unit 5 adopts a chip TMS320F28377, which is a single/dual core 32-bit floating point Micro Control Unit (MCU), the master frequency is up to 200MHz, and two types of single/dual core pin to pin are compatible, and is suitable for various control industrial devices. The method can be used in the fields of intelligent meter reading, power line communication, digital power supplies, solar micro inverters and converters, industrial driving products and the like.
The pulse switching unit 7 adopts a chip 74LVX 3245; the chip 74LVX3245 is a dual power, 8-bit conversion transceiver designed to interface between a 3V bus and a 5V power environment. Pin 22 is output and input enable pin of/OE, and when/OE is low, the chip 74LVX3245 can transmit data; when/OE is high, the A and B ports are disabled, and the A and B ports are high impedance and cannot transmit data. The input of transmitting/receiving (T/R) is used for determining the direction of data flow, when the (T/R) is high level, data is input from the A port, and data is output from the B port; when (T/R) is low, data is input from the B port and output from the A port.
Chip ISO7421 can provide current isolation up to 1 minute and up to 2500VRMS in compliance with UL standards, and 4242VPK isolation in compliance with VDE standards; these devices have 2 isolation channels (i.e., chip ISO7421 has two isolation channels in opposite directions and a signal transmission rate >50Mbps), each isolation channel has a logic input and output buffer, and the two devices are separated by a silicon diode (SiO2) insulated gate. By use with an isolated power supply, these devices can prevent noise currents on the data bus or other circuitry from entering local ground and interfering with or damaging sensitive circuitry. The two isolated channels of each chip ISO7421 are respectively connected in series with the chip 74LVX3245 through a current-limiting resistor, for example, one chip ISO7421 is connected in series with the chip 74LVX3245 through current-limiting currents R1, R2, and the other chip ISO7421 is connected in series with the chip 74LVX3245 through current-limiting currents R3, R4.
The current limiting currents R1, R2, R3 and R4 are mainly used for limiting the excessive current and damaging the chip 74LVX3245 and ISO7421, and play a role in protection.
The utility model discloses in, the degree of accuracy grade of installation formula stopwatch is 0.02 level.
The utility model discloses in, still include the host computer, a wireless communication module is connected through the net twine to the host computer, and wireless transceiver module 10 communication on wireless communication module and the installation formula standard table is connected, and wireless transceiver module 10 is connected with 5 electricity of DSP data processing unit. The upper computer is used for receiving data detected by the installation type standard meter and controlling the DSP data processing unit to set the pulse terminal to output active pulses and reactive pulses or set the pulse terminal to input the active pulses and the reactive pulses of the tested electric energy meter.
The pulse terminal of the installation type standard meter has 4 working modes, 1) outputs low-frequency active pulse and low-frequency reactive pulse; 2) outputting high-frequency active pulse and high-frequency reactive pulse; 3) outputting active pulses and reactive pulses, as shown in fig. 3; 4) the active pulse and the reactive pulse of the electric energy meter to be calibrated are input, and the figure 4 shows.
The utility model discloses in, the high low frequency pulse switching mode of installation formula standard table controls the realization through installation formula standard table DSP data processing unit. The default outputs are low-frequency active pulse and low-frequency reactive pulse, when necessary, a command set to high frequency can be sent by the upper computer, and the DSP data processing unit 5 controls the pulse terminal 9 to output high-frequency active pulse and high-frequency reactive pulse.
Referring to fig. 2, the utility model discloses well installation formula standard meter realizes the principle that active pulse, idle pulse input-output switch:
Pin/OE of chip 74LVX3245 is set low, and pin/OE is tied to digital ground GND.
1. The pulse terminal outputs active pulse and reactive pulse working modes:
when pin/OE of the chip 74LVX3245 is set to a low level, pin P2 of the chip TMS320F28377 in the DSP data processing unit outputs a high level, pin T/R of 74LVX3245 is set to a high level, pin P4 of the chip TMS320F28377 in the DSP data processing unit outputs an active pulse, the active pulse passes through pin a1 of the chip 74LVX3245, is output from pin B1 of the chip 74LVX3245, passes through a current limiting resistor R2, enters a pin INB of the U1 chip ISO7421, is output from pin ISO7421 OUTB of the U1 chip, and enters an active pulse terminal, and the pulse terminal is used as an output terminal to output an active pulse at this time, which is shown in fig. 3.
When pin/OE of the chip 74LVX3245 is set to a low level, pin P2 of the chip TMS320F28377 in the DSP data processing unit outputs a high level, pin T/R of 74LVX3245 is set to a high level, pin P6 of the chip TMS320F28377 in the DSP data processing unit outputs a reactive pulse, the reactive pulse passes through pin A3 of the chip 74LVX3245, is output from pin B3 of the chip 74LVX3245, passes through a current limiting resistor R4, enters pin INB of the U2 chip ISO7421, is output from pin OUTB of the U2 chip ISO7421, and enters a reactive pulse terminal, and the pulse terminal is used as an output terminal to output the reactive pulse at this time, which is shown in fig. 3.
The active pulse of the installation type standard meter is an electric energy parameter calculated by the output DSP data processing unit 5 and is connected with the pulse terminal of the installation type standard meter, when the precision of the installation type standard meter needs to be detected, the pulse terminal of the installation type standard meter can be connected with the standard meter for verification, and the source tracing of the installation type standard meter is realized; the reactive pulse of the installation type standard meter is an electric energy parameter calculated by the output DSP data processing unit 5 and is connected with the pulse terminal of the installation type standard meter, when the precision of the installation type standard meter needs to be detected, the pulse terminal of the installation type standard meter can be connected by the standard meter for verification, and the tracing of the installation type standard meter is realized.
2. The pulse terminal inputs the working modes of active pulse and reactive pulse of the electric energy meter to be detected:
when the active pulse of the electric energy meter to be calibrated is received at the pulse terminal, the pulse terminal is used as an input terminal to input the active pulse. Setting a pin/OE of a chip 74LVX3245 to be a low level, outputting the low level by a pin P2 of a chip TMS320F28377 in a DSP data processing unit, setting a pin T/R of the chip 74LVX3245 to be the low level, enabling an active pulse to enter a pin INA of a U1 chip ISO7421, outputting from a pin OUTA of the U1 chip ISO7421, passing through a current-limiting resistor R1, entering a pin B0 of the chip 74LVX3245, outputting from a pin A0 of the chip 74LVX3245, entering a pin P3 of a chip TMS320F28377 in the DSP data processing unit, measuring the active pulse by the DSP data processing unit, obtaining an active pulse electric energy parameter of the corrected electric energy meter, comparing the active pulse electric energy parameter with an active pulse electric energy parameter measured by a mounting type standard meter, and calculating the active pulse error precision of the corrected electric energy meter, and referring.
When the reactive pulse of the electric energy meter to be calibrated is connected at the pulse terminal, the pulse terminal is used as an input terminal to input the reactive pulse. Setting a pin/OE of a chip 74LVX3245 to be a low level, outputting the low level by a pin P2 of a chip TMS320F28377 in a DSP data processing unit, setting a pin T/R of the chip 74LVX3245 to be the low level, enabling reactive pulses to enter a pin INA of a U2 chip ISO7421 in the DSP data processing unit, outputting the pins OUTA of the U1 chip ISO7421 through a current-limiting resistor R3, entering a pin B2 of the chip 74LVX3245, outputting the pins A2 of the chip 74LVX3245, entering a pin P5 of a chip TMS320F28377 in the DSP data processing unit, and metering the reactive pulses by the DSP data processing unit to obtain reactive pulse electric energy parameters of the calibrated electric energy meter and comparing the reactive pulse electric energy parameters metered by a mounting type standard meter to calculate the reactive pulse error precision of the calibrated electric energy meter, and see FIG. 4.
The utility model provides an installation formula standard table, the pulse terminal 9 that the default set up installation formula standard table of dispatching from the factory exports active pulse, idle pulse as output terminal. When the error accuracy of the installation type standard meter is verified, the installation type standard meter outputs the standard meter with higher wiring accuracy of active pulse and reactive pulse, and the error accuracy of the installation type standard meter is verified.
When the pulse terminal 9 of the installation type standard table is set as an input terminal, the upper computer internal setting software sends a setting command, the setting command is sent to the wireless communication module through a network cable, the antenna of the wireless communication module sends out a signal, the wireless transceiver module 10 on the installation type standard table receives the signal and sends the setting command to the DSP data processing unit 5 in the installation type standard table, the pin P2 of the chip TMS320F28377 in the DSP data processing unit 5 of the installation type standard table outputs a low level, the pin T/R of the 74LVX3245 is set to be a low level, and the pulse terminal 9 of the installation type standard table is set as an input terminal at the moment. And connecting the active pulse and the reactive pulse of the electric energy meter to be calibrated to a pulse terminal 9 of the installation type standard meter, receiving the active pulse and the reactive pulse of the electric energy meter to be calibrated by the installation type standard meter, metering, comparing a metering result with the electric energy parameter metered by the installation type standard meter, and calculating the error precision of the electric energy meter to be calibrated. The utility model provides a measure by the new examination mode of the error precision of school's electric energy meter for by the more diversified of school's electric energy meter examination.
The above-mentioned embodiments only express the specific embodiments of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention.
Claims (7)
1. An installation type standard meter with a pulse input and output switching function comprises a voltage sampling circuit (1), a current sampling circuit (2), a voltage channel ADC converter (3), a current channel ADC converter (4), a DSP data processing unit (5) and an RS485 communication interface (6), and is characterized by further comprising a pulse switching unit (7), two current isolation modules (8), a pulse terminal (9) and a wireless transceiving module (10), wherein the voltage sampling circuit (1) is connected with the DSP data processing unit (5) through the voltage channel ADC converter (3); the current sampling circuit (2) is connected with the DSP data processing unit (5) through a current channel ADC converter (4); the DSP data processing unit (5) is also respectively electrically connected with the pulse switching unit (7), the wireless transceiver module (10) and the RS485 communication interface (6), and the pulse switching unit (7) is electrically connected with the pulse terminal (9) through the two current isolation modules (8).
2. The mounted standard meter with the pulse input and output switching function according to claim 1, further comprising a liquid crystal screen (11), wherein the liquid crystal screen (11) is electrically connected with the DSP data processing unit (5).
3. The mounted standard table with the pulse input and output switching function according to claim 1, wherein the DSP data processing unit (5) adopts a chip TMS320F 28377.
4. The mounted standard watch with the pulse input-output switching function according to claim 1, wherein the pulse switching unit (7) adopts a chip 74LVX 3245.
5. The mounted standard meter with the pulse input-output switching function according to claim 4, wherein each galvanic isolation module (8) comprises a chip ISO7421, the chip ISO7421 has two isolation channels, each isolation channel has a logic input and output buffer, and each isolation channel is connected in series with a chip 74LVX3245 through a current limiting resistor.
6. The mounted standard meter with the pulse input and output switching function as claimed in any one of claims 1 to 5, wherein the accuracy level of the mounted standard meter is 0.02 level.
7. The installation type standard meter with the pulse input and output switching function according to any one of claims 1 to 5, further comprising an upper computer, wherein the upper computer is in communication connection with the DSP data processing unit (5) and is used for receiving data detected by the installation type standard meter and controlling the DSP data processing unit (5) to set the pulse terminal (9) to output active pulses and reactive pulses or set the pulse terminal (9) to input active pulses and reactive pulses of a tested electric energy meter.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116739307A (en) * | 2023-08-09 | 2023-09-12 | 广东电网有限责任公司 | Verification unit checking and scheduling method, system, equipment and storage medium |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116739307A (en) * | 2023-08-09 | 2023-09-12 | 广东电网有限责任公司 | Verification unit checking and scheduling method, system, equipment and storage medium |
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