CN211979181U

CN211979181U - Calibration device of universal meter

Info

Publication number: CN211979181U
Application number: CN201921737638.8U
Authority: CN
Inventors: 杨康; 黄天展; 马庆云; 黄品高; 于文龙; 翁恭伟; 朱显忠; 高超
Original assignee: Guilin Huayi Peakmeter Technology Co ltd
Current assignee: Guilin Huayi Peakmeter Technology Co ltd
Priority date: 2019-10-16
Filing date: 2019-10-16
Publication date: 2020-11-20
Anticipated expiration: 2029-10-16

Abstract

The embodiment of the application provides a calibration device of universal meter, includes: the device comprises an optical signal detector, a coder-decoder and a calibration source interface, wherein the optical signal detector is connected with the coder-decoder, and the coder-decoder is connected with the calibration source interface; the optical signal detector is used for detecting a first visible light signal output by the multimeter, and the first visible light signal represents a first function type to be calibrated and a first value to be calibrated of the multimeter; the coder-decoder is used for analyzing the first visible light signal to obtain a first function type to be calibrated and a first value to be calibrated; and the calibration source interface is used for indicating the calibration source to output a first calibration analog quantity according to the first function type to be calibrated and the first value to be calibrated, and the first calibration analog quantity is used for realizing the measurement of the first function type to be calibrated of the multimeter. By implementing the embodiment of the application, the labor can be saved, the calibration efficiency is improved, and the user experience is improved.

Description

Calibration device of universal meter

Technical Field

The application relates to the technical field of electronic communication, in particular to a calibration device of a universal meter.

Background

Digital multimeters are a versatile electronic measurement instrument that typically includes functions such as an ammeter, voltmeter, ohmmeter, and the like, also known as "multimeters".

Before the digital multimeter leaves a factory, calibration of each gear parameter is carried out to ensure the accuracy of multimeter measurement. The calibration of the multimeter instrument mainly involves parameters such as direct voltage, alternating voltage, direct current, alternating current, capacitance, resistance, and the like. At present, the calibration process of the universal meter is generally completed by manual operation, the calibration point is output by the manual control calibration device, the calibration point is collected by the manual control universal meter, calibration is carried out, and manual inspection is needed after calibration is completed.

The calibration mode is complex to operate, needs to consume a large amount of manpower, and has long calibration time and low efficiency.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a calibrating device of universal meter, uses the device to calibrate the universal meter, can overcome prior art's defect, raises the efficiency, promotes the user and uses experience.

In a first aspect, an embodiment of the present application provides a calibration apparatus for a multimeter, the calibration apparatus including: the device comprises an optical signal detector, a coder-decoder and a calibration source interface, wherein the optical signal detector is connected with the coder-decoder, and the coder-decoder is connected with the calibration source interface;

the optical signal detector is used for detecting a first visible light signal output by the multimeter, and the first visible light signal represents a first function type to be calibrated and a first value to be calibrated of the multimeter;

the codec is used for analyzing the first visible light signal to obtain the first function type to be calibrated and a first value to be calibrated;

the calibration source interface is used for indicating a calibration source to output a first calibration analog quantity according to the first function type to be calibrated and the first value to be calibrated, and the first calibration analog quantity is used for realizing measurement of the first function type to be calibrated of the multimeter.

It can be seen that, when the calibration device provided in this embodiment of the present application is used to calibrate a multimeter, the calibration device receives a first visible light signal output by the multimeter through the optical signal detector, where the first visible light signal represents a first function type to be calibrated and a first value to be calibrated of the multimeter, the codec decodes and analyzes the optical signal to obtain a calibration instruction, and then the calibration source interface instructs the calibration source to output a first calibration analog quantity according to the calibration instruction. In some implementations, when the multimeter has the capability of calculating the calibration coefficient, the multimeter can measure the first calibration analog quantity to obtain a measurement value, and then calculate a new calibration function (or called calibration equation) according to the first value to be calibrated and the measurement value, where the calibration function includes a new calibration coefficient corresponding to the first function type to be calibrated, and subsequently, in the measurement of the first function type to be calibrated, the multimeter can calibrate the new measurement value of the first function type to be calibrated by using the calibration function, thereby realizing the calibration of the measurement value of the first function type to be calibrated of the multimeter. Therefore, the embodiment of the application can automatically calibrate the multimeter in a visible light communication mode, so that the labor cost is reduced, the working efficiency is improved, and the user experience is improved.

In addition, it can be seen that in the embodiment of the application, the calibration device receives the calibration instruction of the multimeter in a visible light communication mode instead of a wired communication mode, so that the defect of signal interference introduced in a wired communication mode is avoided, and the robustness is ensured.

In a possible embodiment, the first visible light signal includes at least one of a light-on/off changing state and a light-intensity changing state of light emitted by the light-emitting device.

It can be seen that, in the embodiment of the present application, the first visible light signal may be a light on/off changing state of light emitted by the light emitting device, and may also be a light intensity changing state of light emitted by the light emitting device, where the light on/off changing state or the light intensity changing state may represent a meaning included in the first visible light. Therefore, the method and the device can fully express the instruction and meaning of the multimeter comprehensively, and therefore the multimeter can be accurately calibrated.

Based on the first aspect, in a possible implementation manner, the calibration apparatus further includes an analog input interface and an analog output interface; the analog quantity input interface is used for acquiring the first calibration analog quantity output by the calibration source, and the analog quantity output interface is used for outputting the first calibration analog quantity to the multimeter.

It can be seen that in the embodiment of the present application, an analog quantity input interface and an analog quantity output interface exist on the calibration device, and the calibration device can output the first calibration analog quantity obtained from the calibration source to the multimeter through the analog quantity input interface and the analog quantity output interface. Therefore, the embodiment of the application can be implemented to effectively output the first calibration analog quantity to the multimeter through the analog quantity output interface, so that the method and the device are used for measuring the multimeter.

Based on the first aspect, in a possible implementation, the calibration source interface is configured to instruct the calibration source to output the first calibration analog quantity to the multimeter.

It can be seen that, in the embodiment of the present application, the calibration apparatus may also instruct the calibration source to output the first calibration analog quantity through the calibration source interface, and then directly output the first calibration analog quantity to the multimeter for measurement of the multimeter. Therefore, by implementing the embodiment of the application, the first calibration analog quantity output by the calibration source can be quickly and directly output to the multimeter, so that the method and the device are used for measurement of the multimeter.

Based on the first aspect, in a possible implementation, the calibration apparatus further includes a processor;

the optical signal detector is further used for detecting a second visible light signal output by the multimeter, the second visible light signal represents a first function type to be calibrated and a first measurement value of the multimeter, and the first measurement value is obtained by measuring the first calibration analog quantity;

the codec is further configured to parse the second visible light signal to obtain the first function type to be calibrated and the first measurement value;

the processor is used for calculating a calibration coefficient according to the first value to be calibrated and the first measurement value, and the calibration coefficient is used for calibrating a first function type to be calibrated of the multimeter.

It can be seen that in the embodiment of the present application, the calibration device further comprises a processor, and if the calculation function of the multimeter is weak or the multimeter has no function of calculating the calibration coefficient, the calibration device can calculate the calibration coefficient by using the calculation function of the processor, wherein the calibration coefficient is used for calibrating the first function type to be calibrated of the multimeter. Specifically, an optical signal detector of the calibration device receives a second visible light signal output by the multimeter, wherein the second visible light signal represents a first function type to be calibrated and a first measurement value of the multimeter, the codec analyzes the second visible light signal to obtain first measurement value data, and the processor calculates a calibration coefficient according to a first calibration value to be calibrated and the first measurement value. Therefore, by implementing the embodiment of the application, the calibration device can also be used for calculating the calibration coefficient of the first function type to be calibrated of the multimeter, and the calculation capability of the calibration device is improved.

In a possible embodiment, based on the first aspect, the calibration apparatus further comprises a light emitting device; the light-emitting device is used for sending a third visible light signal to the multimeter, and the third visible light signal represents the calibration coefficient used by the multimeter for measuring the first function type to be calibrated.

It can be seen that, in this embodiment of the application, the calibration apparatus further includes a light emitting device, if the calculation function of the multimeter is weak or the multimeter does not have the function of calculating the calibration coefficient, the calibration apparatus may use the light emitting device to emit the calculated calibration coefficient in the form of a third visible light signal, accordingly, the multimeter uses the light signal detector to receive the third visible light signal and analyze the third visible light signal to obtain the calibration coefficient, and the multimeter obtains a new calibration function according to the calibration coefficient to complete calibration of the multimeter. And subsequently, in the measurement of the first function type to be calibrated, the multimeter can utilize the calibration function to calibrate the newly measured measurement value of the first function type to be calibrated, so that the calibration of the measurement value of the first function type to be calibrated of the multimeter is realized. Therefore, according to the embodiment of the application, the calibration device can send data to the multimeter in an optical communication mode, and user experience is improved.

Based on the first aspect, in a possible embodiment, the optical signal detector is further configured to detect a fourth visible light signal output by the multimeter, where the fourth visible light signal characterizes a first function type to be calibrated and a second function type to be calibrated of the multimeter;

the codec is further configured to parse the fourth visible light signal to obtain the first function type to be calibrated and the second function type to be calibrated;

the calibration source interface is further configured to instruct the calibration source to output a second calibration analog quantity according to the first function type to be calibrated and a second value to be calibrated, where the second calibration analog quantity is used for measuring the first function type to be calibrated of the multimeter;

the optical signal detector is further configured to detect a fifth visible light signal output by the multimeter, where the fifth visible light signal represents the first function type to be calibrated and a second measurement value of the multimeter, and the second measurement value is obtained by measuring the second value to be calibrated;

the codec is further configured to analyze the fifth visible light signal to obtain the first function type to be calibrated and a second measurement value;

the processor is also used for realizing the verification of the first function type to be calibrated of the multimeter according to the first calibration value to be calibrated and the second measurement value.

It can be seen that, in the embodiment of the present application, after the calibration device is used to calibrate the multimeter, the calibration device can be used to implement the inspection of the multimeter, check whether the calibration process is correct, and the processor performs calculation according to the first calibration value to be calibrated and the second measurement value to implement the inspection of the first function to be calibrated of the multimeter. Therefore, by implementing the embodiment of the application, after the calibration of the multimeter is finished, the test process can be continued to ensure the correctness of the calibration process.

Based on the first aspect, in a possible implementation manner, the calibration apparatus further includes a relay, and the relay is connected with the analog input interface; the relay is used for acquiring the first calibration analog quantity transmitted by the analog quantity input interface through switching the state of the switch according to the first function type to be calibrated.

It can be seen that, in the embodiment of the present application, the calibration apparatus further includes a relay, and the relay is capable of switching the switch state according to the first function type to be calibrated, so as to obtain the first calibration analog quantity output by the calibration source and transmitted through the analog quantity input interface. Therefore, the embodiment of the application is implemented, and automatic calibration of the multimeter is facilitated through control of the relay.

In a possible embodiment, based on the first aspect, the relay is further configured to obtain the second calibration analog quantity transmitted by the analog quantity input interface by switching a switch state according to the first function type to be calibrated.

It can be seen that, in the embodiment of the present application, the relay may also switch according to the first function type to be calibrated, and obtain the second calibration analog quantity transmitted by the analog quantity input interface, where the second calibration analog quantity is output by the calibration source and is used for the multimeter to perform the process of checking the first function type to be calibrated. Therefore, the embodiment of the application is implemented, and the automatic verification of the multimeter is facilitated through the control of the relay.

Based on the first aspect, in a possible implementation, the calibration apparatus includes: the coder-decoder is connected with the relay, and the relay is connected with the resistance-capacitance matrix circuit;

the optical signal detector is used for detecting a sixth visible light signal output by the multimeter, and the sixth visible light signal represents a second function type to be calibrated and a third value to be calibrated of the multimeter;

the codec is configured to parse the sixth visible light signal to obtain the second function type to be calibrated and a third value to be calibrated;

the relay is used for switching the switch state according to the second function type to be calibrated;

the resistor-capacitor matrix circuit is used for outputting a third calibration analog quantity through the control of the relay switch state;

the analog quantity output interface is used for outputting a third calibration analog quantity to the multimeter, and the third calibration analog quantity is used for measuring the second function type to be calibrated of the multimeter.

It can be seen that, in this embodiment of the application, the calibration apparatus further includes a relay and a resistance-capacitance matrix circuit, and the specific calibration process includes that the optical signal detector receives a sixth visible light signal output by the multimeter, where the sixth visible light signal represents a second function type to be calibrated and a third value to be calibrated, the codec parses the sixth visible light signal to obtain a calibration instruction, the relay switches a switch state according to the calibration instruction, and controls the resistance-capacitance matrix circuit to output a third calibration analog quantity, and then outputs the third calibration analog quantity to the multimeter through the analog quantity output interface for measuring the second function type to be calibrated. By implementing the embodiment of the application, the calibration device can be used for automatically calibrating the second function type to be calibrated of the multimeter, so that all gears and parameters of the multimeter can be calibrated, and the comprehensiveness, the sufficiency and the accuracy of calibration are ensured.

In a second aspect, embodiments of the present application provide a system, including a calibration apparatus, a multimeter, and a calibration source, where the calibration apparatus is the calibration apparatus described in any of the embodiments of the first aspect; the multimeter comprises a light-emitting device and an optical signal detector, wherein the light-emitting device is used for emitting visible light signals of at least one of the on-off change state and the intensity change state of light, and the optical signal detector is used for detecting the visible light signals emitted by the calibration device; the calibration source is used for outputting a calibration analog quantity, and the calibration analog quantity is used for measurement of a multimeter calibration process or measurement of a detection process.

It can be seen that the present application provides a calibration apparatus for a multimeter. The calibration device receives a calibration instruction sent by the multimeter in an optical communication mode, and does not need to be accessed in a wired mode, so that interference caused by wired communication is successfully avoided; the calibration device is used in the calibration process of the multimeter to realize automatic calibration of the multimeter, and can also be used for checking the calibration result after the calibration is finished to realize automatic checking; the calibration device can be used for calculating a calibration coefficient, and then the calibration coefficient is sent to the universal meter in an optical communication mode for calibration of the universal meter; utilize this calibrating device to calibrate the universal meter, not only use manpower sparingly, and shorten calibration time, improved work efficiency, promoted user experience.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a calibration system for two multimeters provided by an embodiment of the present application;

FIG. 2A is a schematic structural diagram of a specific calibration apparatus, multimeter, and calibration source provided herein;

FIG. 2B is a schematic diagram of another embodiment of a calibration apparatus, multimeter, and calibration source provided herein;

FIG. 3 is a more specific embodiment provided herein;

fig. 4 is a schematic structural diagram of a resistor-capacitor matrix circuit according to an embodiment of the present disclosure;

FIG. 5 is yet another more specific embodiment provided herein.

Detailed Description

The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It is to be understood that the terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only, and is not intended to be limiting of the application. As used in the examples of this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is noted that, as used in this specification and the appended claims, the term "comprises" and any variations thereof are intended to cover non-exclusive inclusions. For example, a system, article, or apparatus that comprises a list of elements/components is not limited to only those elements/components but may alternatively include other elements/components not expressly listed or inherent to such system, article, or apparatus.

It is also understood that the term "if" may be interpreted as "when", "upon" or "in response to" determining "or" in response to detecting "or" in the case of … "depending on the context.

It should also be noted that the terms "first," "second," "third," "fourth," and the like in the description and in the claims, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order.

Referring to FIG. 1, FIG. 1 is a block diagram of a calibration system for two multimeters provided in accordance with an embodiment of the present application involving a multimeter 11, a calibration apparatus 10 or a calibration apparatus 20, and a calibration source 12. The multimeter 11 is provided with a device having a light emitting characteristic, such as an illuminating lamp, a status display lamp or other devices capable of emitting visible light. Multimeter 11 can emit a visible light signal. Accordingly, calibration device 10 or calibration device 20 can receive visible light signals emitted by multimeter 11. The visible light signal output by multimeter 11 can be characterized by at least one of on-off changing state and intensity changing state, and the function type and value of the signal include: for example, the function type and value of the signal can be represented by the on/off changing state, the on represents "1", the off represents "0", the first three bits of the visible light signal represent the function type, wherein "001" represents the voltage type, "010" represents the current type, "011" represents the resistance type, "100" represents the capacitance type, "101" represents the frequency type, etc., the fourth bit to the ninth bit represent the integer part of the value, the tenth bit to the thirteenth bit represent the decimal part of the value, "0010000100000" represents the voltage 2.0 volts, "0100000000010" represents the current 0.2 amperes, and "0110100010000" represents the resistance 17.0 ohms, etc.

Fig. 1 (1) is a schematic structural diagram of a calibration system provided in an embodiment of the present application, and a calibration apparatus 10 is connected to a multimeter 11 and a calibration source 12, respectively. In the calibration process, the multimeter 11 outputs a visible light signal (the visible light signal may also be referred to as a first visible light signal) by using the light emitting device, accordingly, the calibration device 10 receives the visible light signal and analyzes the visible light signal, the calibration source 12 is controlled to output a calibration analog quantity (the calibration analog quantity may also be referred to as a first calibration analog quantity) according to an instruction obtained by the analysis, the calibration source 12 then sends the output calibration analog quantity to the multimeter 11 through the calibration device 10 for measurement of the multimeter 11, and the multimeter 11 performs calibration according to a measurement value (the measurement value may also be referred to as a first measurement value).

In one embodiment, calibration apparatus 10 has a light emitting device capable of emitting visible light, and multimeter 11 has a device capable of receiving and analyzing visible light. The multimeter 11 can also send the above measurement value to the calibration device 10 in an optical communication manner, that is, the multimeter 11 outputs a visible light signal (the visible light signal may also be referred to as a second visible light signal), the calibration device 10 correspondingly receives and analyzes the visible light signal, and a calibration coefficient is calculated according to the data obtained by the analysis. The calibration device 10 then sends the calibration coefficients to the multimeter 11, again by way of optical communication, and the multimeter 11 performs calibration based on the calibration coefficients.

In yet another embodiment, both calibration apparatus 10 and multimeter 11 have Bluetooth installed thereon, calibration apparatus 10 can transmit the calibration coefficients to multimeter 11 by way of Bluetooth transmission, and multimeter 11 performs calibration based on the received calibration coefficients.

Fig. 1 (2) is a schematic structural diagram of another calibration system provided in the embodiment of the present application. Calibration apparatus 20 is connected to calibration source 12, and calibration source 12 is connected to multimeter 11. In the calibration process, the multimeter 11 outputs a visible light signal (the visible light signal may also be referred to as a first visible light signal) by using the light emitting device, accordingly, the calibration device 20 receives the visible light signal, analyzes the visible light signal, controls the calibration source 12 to output a calibration analog quantity (the calibration analog quantity may also be referred to as a first calibration analog quantity) according to an instruction obtained by the analysis, and then the calibration source 12 directly sends the output calibration analog quantity to the multimeter 11 for measurement of the multimeter 11, and the multimeter 11 performs calibration according to a measurement value (the measurement value may also be referred to as a first measurement value).

In one embodiment, calibration apparatus 20 has a light emitting device capable of emitting visible light, and multimeter 11 has a device capable of receiving and analyzing visible light. The multimeter 11 can also transmit the above measurement value to the calibration device 20 through optical communication, that is, the multimeter 11 outputs a visible light signal (the visible light signal may also be referred to as a second visible light signal), and the calibration device 20 correspondingly receives and analyzes the visible light signal, and calculates a calibration coefficient according to the data obtained by the analysis. Calibration device 20 then sends the calibration coefficients to multimeter 11, again by way of optical communication, and multimeter 11 performs calibration based on the calibration coefficients.

In yet another embodiment, both calibration apparatus 20 and multimeter 11 have Bluetooth installed thereon, calibration apparatus 20 can transmit the calibration coefficients to multimeter 11 via Bluetooth transmission, and multimeter 11 performs calibration based on the received calibration coefficients.

Referring to fig. 2A and 2B, fig. 2A and 2B are schematic structural diagrams of specific embodiments provided by embodiments of the present application based on the system architecture.

Referring to fig. 2A, fig. 2A is a schematic structural diagram of a specific calibration apparatus 10, a multimeter 11 and a calibration source 12 provided in an embodiment of the present application. The calibration device 10 includes: the device comprises an optical signal detector 101, a codec 102, a calibration source interface 103, a relay 106, a resistance-capacitance matrix circuit 105, an analog interface 107 and a man-machine interaction interface 104, wherein the codec 102 is respectively connected with the optical signal detector 101, the calibration source interface 103 and the relay 106, and the relay 106 is respectively connected with the resistance-capacitance matrix circuit 105 and the analog interface 107.

The optical signal detector 101 is configured to receive a visible light signal output by the multimeter and convert the optical signal into a digital signal. In a specific embodiment, the optical signal detector 101 may be a photosensitive sensor and a voltage comparator, or a photosensitive sensor and an analog-to-digital AD collecting device, or a photoelectric switch, etc., where the photosensitive sensor can convert an optical signal into an electrical signal, the voltage comparator or the analog-to-digital AD collecting device can convert an analog electrical signal into a digital signal, and the photoelectric switch can directly convert a received optical signal into a digital signal.

The codec 102 is configured to decode and analyze the digital signal to obtain a control command. The codec 102 may be a micro control unit MCU, or may be a specific type of single chip microcomputer, such as STM32F103C8T 6.

The calibration source interface 103 is configured to instruct the calibration source to output a calibration analog quantity (the calibration analog quantity may be a first calibration analog quantity or a second calibration analog quantity) according to the control instruction parsed by the codec 102, and in a specific embodiment, the calibration source interface 103 may be an RS232 interface or an ethernet port, etc.

The relay 106 is configured to switch the switch according to the control instruction obtained by the codec 102, select the calibration analog to be obtained, and output the calibration analog to the multimeter 11. For example, when calibrating the voltage or the current, the relay 106 switches the switch to the calibration source 12 side for obtaining the calibration analog quantity output by the calibration source 12 (the calibration analog quantity may also be referred to as a first calibration analog quantity); when calibrating the resistor or the capacitor, the relay 106 switches to the resistor-capacitor matrix circuit 105 side for obtaining the calibration analog quantity output by the resistor-capacitor matrix circuit 105 (the calibration analog quantity may also be referred to as a third calibration analog quantity). In a particular embodiment, the relay 106 may be a switch or the like.

The rc matrix circuit 105 is configured to output a calibration analog quantity (this calibration analog quantity may also be referred to as a third calibration analog quantity) according to switching of the relay 106, the rc matrix circuit 105 is a circuit configured by a plurality of resistors with different values, a plurality of capacitors with different values, and a switch, and when the relay 106 switches the switch to the rc matrix circuit 105 side according to a control instruction, the rc matrix circuit 105 selects an appropriate branch by switching control according to the control instruction, and outputs the calibration analog quantity.

The analog quantity interface 107 is used for outputting the calibration analog quantity output by the calibration source 12 to the multimeter 11.

In one embodiment, the relay 106 may be coupled to the RC matrix circuit 105 or may be a separate device. When the relay 106 is used as a separate device, the relay 106 is connected to the rc matrix circuit 105 and the codec 102, respectively.

In a specific embodiment, the calibration apparatus 10 may further include a human-machine interaction interface 104, and the human-machine interaction interface 104 is connected to the codec 102. The human-machine interface 104 is used for externally connecting some input and output devices as a command input or data reading interface.

Optionally, the calibration apparatus 10 further comprises a processor 109, and the processor 109 may be a stand-alone device or may be coupled to the codec 102 for calculating the calibration coefficients during the auto-calibration process or performing the verification calculation on the calibration results during the auto-verification process.

Optionally, the calibration apparatus 10 further includes a light emitting device 108, the codec 102 on the calibration apparatus 10 encodes the calculated calibration coefficient, and then outputs a visible light signal representing the calibration coefficient through the light emitting device 108, and accordingly, the multimeter 11 receives the visible light through the light signal detector and performs calibration according to the calibration coefficient obtained by analysis.

In an embodiment, the calibration apparatus 10 may further include a power regulator (not shown) for supplying power to the entire calibration apparatus 10 and regulating the voltage of the power supply to the voltage required by the calibration apparatus 10.

In one embodiment, the calibration device 10 further includes a controller (not shown). The controller is disposed on a circuit board of the calibration apparatus 10, and can control devices on the circuit board according to the meaning of the visible light signal representation analyzed by the codec 102. The controller may be implemented by one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components.

In one embodiment, the calibration device 10 further includes a memory (not shown). The memory is used to store program instructions and data including, but not limited to: calibration coefficients, temporary data generated during calibration, such as function type, calibration values, inspection values, nominal value deviation, errors, measurement values, and the like. The Memory may include Random Access Memory (RAM) and Non-Volatile Memory (NVM). The nonvolatile Memory may include a Hard Disk Drive (Hard Disk Drive, HDD), a Solid State Drive (SSD), a Silicon Disk Drive (SDD), a Read-Only Memory (ROM), a Compact Disc Read-Only Memory (CD-ROM), a magnetic tape, a floppy Disk, an optical data storage device, and the like.

In order to more clearly understand the scheme of the present application, an application scenario is described as an example.

For example, in one application scenario, calibration of the voltage steps is required before the multimeter 11 is shipped, to ensure the accuracy of the data measured using the multimeter 11.

In calibrating the voltage level of multimeter 11, a user can set multiple voltage values for calibration to ensure the correctness of the calibration. Assuming that the multimeter 11 outputs a visible light signal (this visible light can be referred to as a first visible light signal) by means of the light emitting device, the visible light signal is characteristic of the calibration voltage (the first type to be calibrated), a V (the first value to be calibrated), the optical signal detector 101 of the calibration apparatus 10 receives the visible light signal output by the multimeter 11, and converts the optical signal into a digital signal, the codec 102 performs decoding analysis on the digital signal to obtain a calibration command which is a calibration voltage (a first type to be calibrated) a V (a first value to be calibrated), then, the relay 106 switches the switch to the calibration source 12 side, the calibration source interface 103 instructs the calibration source 12 to output the voltage analog a 1V (first calibration analog) according to the calibration instruction, and outputs the voltage analog a 1V (first calibration analog) to multimeter 11 through analog interface 107 on calibration apparatus 10. After receiving the voltage analog a 1V (first calibration analog), multimeter 11 measures it to obtain a measurement value a 2V (first measurement value). And repeating the steps, and measuring the other voltages to be calibrated to obtain a plurality of values to be calibrated and a plurality of corresponding measured values (each value to be calibrated corresponds to one measured value). When the multimeter 11 has the function/capability of calculating the calibration coefficient, the multimeter 11 calculates the calibration coefficient according to the plurality of values to be calibrated and the corresponding plurality of measurement values, and the multimeter 11 performs calibration according to the calibration coefficient. Prior to the entire calibration process, the user can set the sequence of values to be calibrated and types of functions to be calibrated for multimeter 11 to automate the entire calibration process.

Alternatively, calibration device 10 may also calculate calibration coefficients when the computing capabilities of multimeter 11 are weak or multimeter 11 does not have the capability/ability to calculate calibration coefficients. Specifically, the optical signal detector 101 receives a visible light signal (a first visible light signal) output by the multimeter 11, converts the visible light signal into a digital signal, the codec 102 performs decoding analysis on the digital signal to obtain a calibration command, which is a calibration voltage (a first type to be calibrated) and a V (a first value to be calibrated), then the relay 106 switches the switch to the calibration source 12 side, the calibration source interface 103 instructs the calibration source 12 to output a voltage analog a 1V (a first calibration analog) according to the calibration command, and outputs the voltage analog a 1V (the first calibration analog) to the multimeter 11 through the analog interface 107 on the calibration device 10, and the multimeter 11 receives the voltage analog a 1V (the first calibration analog) and then measures the voltage analog a 1V to obtain a measured value a 2V (a first measured value). Multimeter 11 then outputs a visible light signal (which may be referred to as a second visible light signal) that is characteristic of the calibration voltage (first type to be calibrated), a 2V (first measurement value). The optical signal detector 101 of the calibration apparatus 10 receives the visible light signal, and the codec 102 analyzes the visible light signal to obtain a 2V (first measurement value) of the multimeter. By repeating the steps, the measurement of a plurality of values to be calibrated is realized, and corresponding measured values can be obtained. The calibration device 10 calculates a calibration coefficient according to a plurality of values to be calibrated and the measured values, and outputs a visible light signal (the visible light can be referred to as a third visible light signal) through a light emitting device on the calibration device 10, the visible light signal represents the calibration coefficient of the calibration function type, correspondingly, the multimeter 11 receives the visible light signal by using an optical signal detector of the multimeter 11, obtains the calibration coefficient through analysis, and completes calibration according to the calibration coefficient.

In addition, the calibration apparatus 10 of the present embodiment of the application can be used for automatic calibration of the multimeter 11, and can also be used for automatic verification of the calibration result after the automatic calibration, and the automatic verification process is as follows.

The optical signal detector 101 receives a visible light signal (the visible light may be referred to as a fourth visible light signal) output by the multimeter 11 in an optical communication manner, the visible light signal ensures a check voltage (the first function type to be calibrated) and dV (the second function type to be calibrated), and converts the visible light signal into a digital signal, then the codec 102 decodes and analyzes the digital signal to obtain a control command calibration voltage (the first function type to be calibrated) and dV (the second function type to be calibrated), the relay 106 switches the switch to the calibration source 12 side, the calibration source interface 103 instructs the calibration source 12 to output a voltage analog d1V (a second calibration analog) to the multimeter 11 according to the check command, after receiving the voltage analog (the second calibration analog), the multimeter 11 measures the voltage analog (the second calibration analog) to obtain a d2V (a second measurement value), and then the multimeter checks the check voltage (the second function type to be calibrated) again by using visible light (the visible light may be referred to as a fifth visible light signal) ) D2V, the optical signal detector 101 of the calibration device 10 receives the visible light signal and converts the visible light signal into a digital signal, the codec 102 decodes the digital signal to obtain a calibration voltage d2V, then the calibration device 10 calculates according to d2V and dV, and checks whether the calibration result is correct according to the calculation result, and meanwhile, the calibration device can also be externally connected with a display screen through the man-machine interaction interface 104 to output and display the calculation result, or is externally connected with a computer through a USB interface to send the calculation result to the computer and the like.

Referring to fig. 2B, fig. 2B is a schematic structural diagram of another specific calibration apparatus 20, multimeter 11 and calibration source 12 provided in the embodiment of the present application. The calibration device 20 includes: the optical signal detector 201, the codec 202 and the calibration source interface 203, the codec 202 is connected with the optical signal detector 201 and the calibration source interface 203 respectively.

The functions and functions of the optical signal detector 201 and the codec 202 are the same as those of the optical signal detector 101 and the codec 102 in fig. 2A, and are not described herein again.

The calibration source interface 203 is configured to instruct the calibration source 12 to output the first calibration analog quantity according to the control command analyzed by the codec 202, and in a specific embodiment, the calibration source interface 203 may be an RS232 interface or an ethernet port.

In a specific embodiment, the calibration apparatus 20 may further include a human-machine interface 204, and the human-machine interface 204 is the same as the human-machine interface 104 in fig. 2A, and is not described herein again.

Optionally, the calibration apparatus 20 further comprises a processor 209, and the processor 209 may be a stand-alone device or may be coupled to the codec 202 for calculating the calibration coefficients during the auto-calibration process or performing the verification calculation on the calibration results during the auto-verification process.

Optionally, when the multimeter 11 does not have a function of calculating a calibration coefficient, the calibration apparatus 20 further includes a light emitting device 208, the codec 202 on the calibration apparatus 20 encodes the calculated calibration coefficient, and then outputs a visible light signal representing the calibration coefficient through the light emitting device 208, and accordingly, the multimeter 11 receives the visible light through the light signal detector and performs calibration according to the calibration coefficient obtained by analysis.

In an embodiment, the calibration apparatus 20 may further include a power regulator (not shown) for supplying power to the entire calibration apparatus 20 and regulating the voltage of the power supply to the voltage required by the calibration apparatus 20.

In one embodiment, the calibration device 20 further includes a controller (not shown). The controller is disposed on a circuit board of the calibration apparatus 20, and can control devices on the circuit board according to the meaning of the visible light signal representation analyzed by the codec 202. The controller may be implemented by one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components.

In one embodiment, the calibration device 20 further comprises a memory (not shown). The memory is used to store program instructions and data including, but not limited to: calibration coefficients, temporary data generated during calibration, such as function type, calibration values, detection values, measurement values, and the like. The Memory may include Random Access Memory (RAM) and Non-Volatile Memory (NVM). The nonvolatile Memory may include a Hard Disk Drive (Hard Disk Drive, HDD), a Solid State Drive (SSD), a Silicon Disk Drive (SDD), a Read-Only Memory (ROM), a Compact Disc Read-Only Memory (CD-ROM), a magnetic tape, a floppy Disk, an optical data storage device, and the like.

In order to more clearly understand the solution of the present application, the calibration process and the verification process of the calibration device 20 are described below.

The calibration procedure is as follows. The multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a first visible light signal), the visible light signal characterizes a first function type to be calibrated and a first value to be calibrated, the optical signal detector 201 in the calibration apparatus 20 receives the visible light signal and converts the optical signal into a digital signal, the codec 202 decodes and analyzes the digital signal to obtain a calibration instruction, the calibration source interface 203 instructs the calibration source 12 to output a first calibration analog quantity according to the calibration instruction, the first calibration analog quantity of the calibration source 12 is directly output to the multimeter 11, and the multimeter 11 measures the first calibration analog quantity to obtain a first measurement value. Changing the value to be calibrated, repeating the above steps to obtain a plurality of sets of data (a plurality of values to be calibrated and a plurality of corresponding measured values, wherein each value to be calibrated corresponds to one measured value), and calculating the first measured value, the first value to be calibrated and the plurality of sets of data by the multimeter 11 to obtain a calibration coefficient for the calibration process.

Alternatively, the multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a second visible light signal) that represents the first function type to be calibrated and the first measurement value, the optical signal detector 201 in the calibration apparatus 20 receives the visible light signal and converts the visible light signal into a digital signal, and the codec 202 performs decoding analysis on the digital signal to obtain the first function type to be calibrated and the first measurement value. The calibration device 20 calculates a calibration coefficient according to the first measurement value, the first calibration value and the plurality of sets of data. Then, the calibration apparatus 20 outputs again visible light (the visible light signal may be referred to as a third visible light signal) by using the light emitting device, the visible light represents the calibration coefficient corresponding to the calibration function type, and the multimeter 11 receives the visible light, analyzes the visible light to obtain the calibration coefficient, and performs calibration.

After multimeter 11 calibration is complete, the calibration results are verified. The multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a fourth visible light signal), the visible light signal represents a first function type to be calibrated and a second function type to be calibrated, the optical signal detector 201 of the calibration apparatus 20 receives the visible light signal and converts the optical signal into a digital signal, the codec 202 decodes and analyzes the digital signal to obtain a control instruction, the calibration source interface 203 instructs the calibration source 12 to output a second calibration analog quantity according to the calibration instruction, the calibration source 12 directly outputs the second calibration analog quantity to the multimeter 11, and the multimeter 11 measures the second calibration analog quantity to obtain a second measurement value. The multimeter 11 outputs again visible light (this visible light signal may be referred to as a fifth visible light signal) which characterizes the first function type to be calibrated and the second measured value, the optical signal detector 201 of the calibration apparatus 20 receives this visible light and converts the optical signal into a digital signal, the codec 202 performs decoding analysis on the digital signal to obtain the first function type to be calibrated and the second measured value, a check report is calculated according to the first value to be calibrated and the second measured value, and it can be determined whether the calibration result is correct through the check report.

By implementing the scheme of the embodiment of the application, the optical signal detectors (101 and 201) automatically receive the visible light signals sent by the multimeter 11 in an optical communication mode, so that the interference caused by wired communication is successfully avoided; the calibration devices (10 and 20) can be used for an automatic calibration process of the multimeter 11 and can also be used for verifying a calibration result; whole automatic calibration process need not the manually operation instrument, has improved work efficiency, saves time, has also avoided because the potential safety hazard problem that artifical maloperation brought, has promoted user and has used experience.

Referring to FIG. 3, FIG. 3 shows a more specific embodiment of a calibration system provided herein, which includes a calibration apparatus 10, a multimeter 11, and a Fuluke 5080A calibration source 12. The calibration device 10 includes: the system comprises an optical signal detector 101 (comprising a photodiode 1011 and a voltage comparator 1012), an STM 32102, an RS 232103, a human-computer interaction interface 104, a resistance-capacitance matrix circuit 105, a relay 106 and an analog quantity interface 107. The analog quantity interface 107 comprises an analog quantity input interface 1071 and an analog quantity output interface 1072, the analog quantity input interface 1071 is connected with the calibration source 12 of the Fuluke 5080A and used for receiving the calibration analog quantity output by the calibration source 12 of the Fuluke 5080A, and the analog quantity output interface 1072 is connected with the multimeter 11 and used for outputting the calibration analog quantity to the multimeter 11. The human-computer interaction interface 104 includes a touch screen, a USB interface, and the like, the touch screen may be used to output and display data, and may also be used to input some instructions by clicking the touch screen to implement human-computer command interaction, and the USB interface is used to connect a computer for data feedback.

A schematic diagram of the rc matrix circuit 105 is shown in fig. 4. In fig. 4, the rc matrix circuit 105 is composed of a plurality of resistors with different values, a plurality of capacitors with different values, and a plurality of switches, wherein the switches may be analog switches or relay switches. For example, when the capacitor g needs to be calibrated, the switch 8, the switch 11, the switch 14, and the switch 17 are switched to the lower side, the switch 10 is switched to the upper side, and the remaining switches remain unchanged, then the capacitor g is connected to the circuit, and the rc matrix circuit 105 outputs the capacitor analog quantity g.

In the calibration device 10, the photodiode 1011 and the voltage comparator 1012 serve as optical signal detectors, the photodiode 1011 receives an optical signal output by the multimeter 11, and converts the optical signal into an electrical signal according to the on/off state of the optical signal, and the voltage comparator 1012 converts the electrical signal into a digital signal. The single chip microcomputer STM 32102 is used as a coder and decoder, and the STM 32102 decodes and analyzes the digital signals to obtain a calibration instruction. The RS 232103 serves as a calibration source interface, and when receiving a calibration instruction, the RS 232103 instructs the fuilk 5080A to calibrate the source 12 to output a voltage analog quantity or a current analog quantity according to the calibration instruction. Multimeter 11 has a light emitting device thereon, and can output visible light signals in a light-on/off changing state. The reference source 12 of the reference voltage reference circuit is used for calibrating the voltage and the current, namely outputting a voltage analog quantity and a current analog quantity, and cannot be used for calibrating the resistance and the capacitance, namely outputting a resistance analog quantity and a capacitance analog quantity. The calibration source 12 of the Fuluke 5080A is controlled and switched by a single relay switch, and when a voltage and current calibration command is received, the relay 106 controls the switch to be switched to the calibration source 12 of the Fuluke 5080A, so that calibration analog quantity is obtained for calibration.

The calibration device 10 is powered by 220V (or other voltages), and then regulated to 5V by a voltage regulation chip, wherein the voltage regulation chip is L7805C.

The calibration process and the verification process of the calibration apparatus 10 for the multimeter 11 in this embodiment are described below by way of example.

In one example, in calibrating multimeter 11 using calibration device 10, relay 106 can first be connected to a Fulvke 5080A12 calibration source with a banana head connection and connected to a computer via a USB interface.

The multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a sixth visible light signal), the visible light signal represents a calibration resistor (the resistor is a second function type to be calibrated), b (b is a third function type to be calibrated), the photodiode 1011 receives the visible light signal and converts the visible light signal into an electrical signal, the voltage comparator 1012 converts the electrical signal into a digital signal, then the STM 32102 analyzes the digital signal to obtain a control instruction of a calibration resistor b ohm, namely, the relay 106 switches the switch to the resistor-capacitor matrix circuit 105 side, switches the switch 1 and the switch 8 to the upper side, switches the switch 2 and the switch 9 to the lower side, and keeps the rest switches unchanged, so that the resistor-capacitor matrix circuit 105 outputs a resistor analog b ohm (b ohm is a third calibration analog), and outputs the resistor analog b ohm to the multimeter 11 through the analog interface 107. Multimeter 11 measures the received resistance analog b ohms) to obtain a measured value b1 ohms (b1 ohms is the third measured value). And changing the value to be calibrated, repeating the steps to obtain a plurality of groups of data, and calculating by the universal meter 11 according to b1 ohm, b ohm and the measured data to obtain a calibration coefficient for calibration.

In yet another example, calibration results of the above-described resistance types may also be verified.

The multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a seventh visible light signal), the visible light signal represents a calibration resistor (the resistor is a second function type to be calibrated), c ohm (c ohm is a fourth function type to be calibrated), the photodiode 1011 receives the visible light signal and converts the visible light signal into an electrical signal, the voltage comparator 1012 converts the electrical signal into a digital signal, then the STM 32102 analyzes the digital signal to obtain a control instruction for checking the c ohm, namely, the relay 106 switches the switch to the resistor-capacitor matrix circuit 105 side, switches the switch 1 and the switch 10 to the upper side, switches the switch 2, the switch 3 and the switch 8 to the lower side, and keeps the rest switches unchanged, so that the resistor-capacitor matrix circuit 105 outputs a resistor analog quantity c ohm (a fourth calibration analog quantity) and outputs the resistor analog quantity c ohm to the multimeter 11 through an analog quantity interface. Multimeter 11 measures the received resistance analog c ohm to obtain a measured value c1 ohm (c1 ohm is the fourth measured value). The multimeter 11 sends out a visible light signal (the visible light signal may be referred to as an eighth visible light signal) again, the visible light signal represents a calibration resistance (the second function type to be calibrated) and a measured value c1 ohm, the photodiode 1011 receives the visible light and converts the optical signal into an electrical signal, the voltage comparator 1012 converts the electrical signal into a digital signal, the STM 32102 decodes and analyzes the digital signal to obtain the calibration resistance (the resistance is the second function type to be calibrated) and a measured value c1 ohm, and calculates and checks whether the calibration process is correct according to c ohm and c1 ohm. The calibration device 10 may also display the calculation result through a touch screen, or send the calculation result to a computer through a USB interface, and the computer generates a test report according to the calculation result.

Referring to fig. 5, fig. 5 shows an embodiment of a more specific calibration system provided herein, which includes a calibration device 20, a multimeter 11, and a calibration source 12 of fluskx 5500A. The calibration device 20 includes: the system comprises an optical signal detector 201 (a photodiode 2011 and a voltage comparator 2012), an STM32202, an RS232203 and a human-computer interaction interface 204. In the calibration device 20, the photodiode 2011, the voltage comparator 2012, the STM32202 and the human-computer interaction interface 204 have the same functions as the photodiode 1011, the voltage comparator 1012, the STM 32102 and the human-computer interaction interface 104 in fig. 3, and when the RS232203 receives a calibration instruction, the RS232203 instructs the fuilk 5500A calibration source 12 to output one of a voltage analog quantity, a current analog quantity, a resistance analog quantity and a capacitance analog quantity according to the calibration instruction. Multimeter 11 has a light emitting device thereon, and can output visible light signals in a light-on/off changing state. The calibration source is a Fulux 5500A calibration source 12, and the Fulux 5500A calibration source 12 can be used for calibrating voltage and current, namely outputting voltage analog quantity and current analog quantity, and can also be used for calibrating resistance and capacitance, namely outputting resistance analog quantity and capacitance analog quantity.

The calibration device is powered by 220V (or other voltages), and then is stabilized to 5V by the voltage stabilizing chip, the voltage stabilizing chip is L7805C, the touch screen is used for outputting and displaying data, or a user inputs some instructions by clicking the touch screen, and the USB interface is used for connecting a computer for data feedback.

The calibration process and the verification process of the calibration apparatus 20 for the multimeter 11 in this embodiment are described below by way of example.

In an example, when the calibration device 20 is used to calibrate the multimeter 11, the multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a first visible light signal), the visible light signal represents a calibration resistance (a first function type to be calibrated), b ohm (a first calibration value to be calibrated), the photodiode 2011 receives the visible light signal and converts the visible light signal into an electrical signal, the voltage comparator 2012 converts the electrical signal into a digital signal, then the STM32202 parses the digital signal to obtain a control command for calibrating the resistance b ohm, the RS232203 instructs the fuilk 5500A calibration source 12 to output a resistance analog quantity b ohm (a first calibration analog quantity), the fuilk 5500A calibration source 12 directly outputs the resistance analog quantity b ohm to the multimeter, and the multimeter 11 measures the received resistance analog quantity b ohm to obtain a measured value b2 ohm (a first measured value). And changing the value to be calibrated, repeating the steps to obtain a plurality of groups of data, and calculating by the universal meter 11 according to b2 ohm, b ohm and the measured data to obtain a calibration coefficient for calibration.

The multimeter 11 outputs a visible light signal (the visible light signal may be referred to as a fourth visible light signal), the visible light signal represents a calibration resistance (a first function type to be calibrated) and c ohm (a second function type to be calibrated), the photodiode 2011 receives the visible light signal and converts the visible light signal into an electrical signal, the voltage comparator 2012 converts the electrical signal into a digital signal, the STM32202 analyzes the digital signal to obtain a control command for checking the resistance c ohm, the RS232203 instructs the fuilk 5500A calibration source 12 to output a resistance analog quantity c ohm (a second calibration analog quantity), the fuilk 5500A calibration source 12 directly outputs the resistance analog quantity c ohm to the multimeter 11, and the multimeter 11 measures the received resistance analog quantity c ohm to obtain a measured value c2 ohm (a second measured value). The multimeter 11 sends a fifth visible light signal, the fifth visible light signal represents a calibration resistance (a first function type to be calibrated) and a measurement value c2 ohm (a second measurement value), the photodiode 2011 receives the visible light, converts the optical signal into an electrical signal, the voltage comparator 2012 converts the electrical signal into a digital signal, the STM32202 performs decoding analysis on the digital signal to obtain the calibration resistance and the measurement value c2 ohm, and calculates and checks whether the calibration result is correct according to c ohm and c2 ohm, and the calibration device 20 can display the calculation result through a touch screen or externally connect a computer through a USB interface, send the calculation result to the computer, and the computer generates a check report and the like according to the calculation result.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to related descriptions of other embodiments for parts that are not described in detail in a certain embodiment.

The foregoing detailed description has been provided for the embodiments of the present application, and the principles and implementations of the present invention have been explained herein using specific examples, which are provided only to help understand the embodiments and their core ideas of the present application; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and applications, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. A calibration device for a multimeter, the calibration device comprising: the device comprises an optical signal detector, a coder-decoder and a calibration source interface, wherein the optical signal detector is connected with the coder-decoder, and the coder-decoder is connected with the calibration source interface;

2. Calibration device according to claim 1,

the first visible light signal comprises at least one of a light-on/off change state and a light-intensity change state of light emitted by the light-emitting device.

3. The calibration device according to claim 2, wherein the calibration device further comprises an analog input interface and an analog output interface;

the analog quantity input interface is used for acquiring the first calibration analog quantity output by the calibration source, and the analog quantity output interface is used for outputting the first calibration analog quantity to the multimeter.

4. Calibration device according to claim 2,

the calibration source interface is used for instructing the calibration source to output the first calibration analog quantity to the multimeter.

5. The calibration device of claim 3, further comprising a processor;

6. The calibration device of claim 5, further comprising a light emitting device;

the light-emitting device is used for sending a third visible light signal to the multimeter, and the third visible light signal represents the calibration coefficient used by the multimeter for measuring the first function type to be calibrated.

7. Calibration device according to claim 5,

the optical signal detector is further used for detecting a fourth visible light signal output by the multimeter, and the fourth visible light signal represents a first function type to be calibrated and a second function type to be calibrated of the multimeter;

8. The calibration device of claim 7, further comprising a relay connected to the analog input interface;

the relay is used for acquiring the first calibration analog quantity transmitted by the analog quantity input interface through switching the state of the switch according to the first function type to be calibrated.

9. Calibration device according to claim 8,

the relay is further used for acquiring the second calibration analog quantity transmitted by the analog quantity input interface through switching the state of a switch according to the first function type to be calibrated.

10. Calibration device according to any of claims 3 or 5-9, characterized in that it comprises: the coder-decoder is connected with the relay, and the relay is connected with the resistance-capacitance matrix circuit;