CN211453926U - An automatic calibration system for digital multimeter - Google Patents

Abstract

This utility model relates to the field of multimeter calibration technology, specifically an automatic calibration system for digital multimeters. It includes a standard source, a terminal block, a camera, an output control module, and an image recognition module. The standard source outputs voltage, resistance, or current signals and is connected to both the output control module and the terminal block. The output control module controls the output signal of the standard source. The terminal block can hold multiple digital multimeters. The camera is connected to the image recognition module; the camera captures images of the multimeter readings, and the image recognition module identifies the readings and records the values. This utility model solves the problem in existing technologies where digital multimeters rely on manual data acquisition, leading to inconsistent data accuracy.

Description

An automatic calibration system for digital multimeter

technical field

The utility model relates to the technical field of multimeter calibration, in particular to an automatic calibration system of a digital multimeter.

Background technique

A digital multimeter is an instrument that uses digital measurement technology to convert analog quantities into digital forms for measurement, calculation and display. It can usually measure parameters such as AC and DC voltage, AC and DC current, and resistance. Digital multimeters are mainly divided into the following three types: laboratory, desktop and hand-held, which are used for various tests in power system operations. The national metrology administrative department has formulated the calibration specifications for digital multimeters. In order to ensure the accuracy of the value, the digital multimeters need to be calibrated regularly.

Because the digital multimeter does not have a program-controlled interface, it can only display the readings through the LED digital tube, and it is difficult to realize the automatic data collection. Therefore, the data collection and recording during the calibration process of the digital multimeter has always been carried out by manual operation. During the calibration process, it is necessary to manually repeatedly set the output value of the standard source and record the measured value, which will inevitably lead to problems such as artificial reading deviation, scribbled handwriting, and recording errors. Manual data copying takes a long time and cannot be guaranteed. Accuracy; and in the calibration process, the phenomenon of overcurrent burnout of the current gear of the digital multimeter often occurs due to improper operation of the test personnel.

Utility model content

The purpose of the invention of the present utility model is: in order to solve the problem that the digital multimeter in the prior art has been relying on manual operation for data collection, resulting in the problem that the data accuracy cannot be guaranteed, the utility model provides an automatic calibration system of the digital multimeter .

In order to solve the problems existing in the prior art, the utility model adopts the following technical solutions:

An automatic calibration system for a digital multimeter, comprising a standard source, a wiring base, a camera, an output control module and an image recognition module; the standard source is used to output voltage, resistance or current signals, and is respectively connected with the output control module and the image recognition module. the wiring base is connected; the output control module is used to control the output signal of the standard source; the wiring base can place a plurality of the digital multimeters; the camera is connected with the image recognition module, and the camera It is used to collect the indication image of the digital multimeter, and the image recognition module is used to identify the indication image and read and record the indication.

As an improvement of the technical scheme of the automatic calibration system of the digital multimeter of the present invention, the standard source is provided with an output terminal; the wiring base is provided with an input terminal group, and the output terminal is in phase with the input terminal group. connect.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the output terminal includes a voltage or resistance output terminal and a current output terminal; the input terminal group includes a voltage input terminal, a resistance input terminal and a current output terminal. an input terminal, the output terminal is correspondingly connected to the input terminal.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the wiring base is provided with six meter positions for fixing the digital multimeter, and each meter position is provided with a connection with the input A connection end connected to the terminal group, and the connection end is connected with the digital multimeter.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the input terminal group further includes a micro-current input terminal, the micro-current input terminal is connected with the connection end, and the micro-current input terminal is connected with the The output ends are connected; a current protection module is arranged between the connection end and the output end.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the area where the camera collects images is the collection area, and the collection area covers the six epitopes.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the standard source is a FLUKE5522A calibrator.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the digital multimeter is a FLUKE179 digital multimeter.

As an improvement of the technical solution of the automatic calibration system of the digital multimeter of the present invention, the camera is an HF900 wide dynamic industrial camera.

Compared with the prior art, the beneficial effects of the present utility model:

1. The output voltage, resistance or current signal of the standard source is controlled by the output control module, which realizes the intelligent control of the output signal;

2. Collect the indication image through the camera, and identify the indication in the indication image through the image recognition module and read the recorded data, which realizes the automation of data collection;

3. Through intelligent control of output signals and automatic data collection, the problem that the digital multimeter in the prior art has been relying on manual operation for data collection has been solved, resulting in the problem that the data accuracy cannot be guaranteed.

Description of drawings

Fig. 1 is the overall schematic diagram of the utility model;

Fig. 2 is the principle schematic diagram of the calibration voltage or resistance of the present utility model;

FIG. 3 is a schematic diagram of the principle of the calibration current of the present invention.

Description of reference numerals: 1-standard source; 2-connection base; 3-camera; 4-output control module; 5-image recognition module; 6-output terminal; 7-input terminal group; 8-voltage or resistance input terminal; 9-current input terminal; 10-micro current input terminal; 11-current protection module; 12-table position.

Detailed ways

In order to make the invention purpose, technical solutions and beneficial effects of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present utility model. The embodiments described above are only a part of the embodiments of the present invention, but not all of the embodiments.

As shown in FIG. 1 , an automatic calibration system of a digital multimeter includes a standard source 1 , a wiring base 2 , a camera 3 , an output control module 4 and an image recognition module 5 .

The standard source 1 is used to output voltage, resistance or current signals and the standard source 1 is connected to the output control module 4 and the wiring base 2 respectively. The output control module 4 is used to control the output signal of the standard source 1, and the wiring base 2 can place multiple digital multimeter. The camera 3 is connected with the image recognition module 5, the camera 3 is used for collecting the indicated value image of the digital multimeter, and the image recognition module 5 is used for recognizing the indicated value image and reading and recording the indicated value.

During calibration, place multiple digital multimeters on the wiring base 2, and control the standard source 1 to output voltage, resistance or current signals to the wiring base 2 through the output control module 4. After the voltage, resistance or current signals pass through multiple digital multimeters , There are numerical values displayed on multiple digital multimeters. After the values are stable, the camera 3 will collect the displayed value image, and the image recognition module 5 will identify the displayed value in the displayed value image and read and record the displayed value, realizing the digital multimeter. of automatic calibration.

In the present invention, the output voltage, resistance or current signal of the standard source 1 is controlled by the output control module 4 to realize the intelligent control of the output signal, then the camera 3 is used to collect the indication image, and then the image recognition module 5 is used to identify the indication Displaying the numbers in the image and reading the records solves the problem that the existing digital multimeters in the prior art always rely on manual operations to collect data, resulting in the problem that the data accuracy cannot be guaranteed.

Further, the standard source 1 is provided with an output terminal 6 , the wiring base 2 is provided with an input terminal group 7 , and the output terminal 6 is connected with the input terminal group 7 . Further, the output terminal 6 includes a voltage or resistance output terminal and a current output terminal, the input terminal group 7 includes a voltage or resistance input terminal 8 and a current input terminal 9, and the output terminal 6 is correspondingly connected to the input terminal.

Specifically, the input terminal group 7 includes a current input terminal 9 and a voltage or resistance input terminal 8. The voltage or resistance input terminal 8 can be a resistance input terminal or a voltage input terminal according to an input signal. The output terminal 6 includes a current output terminal, a voltage or resistance output terminal, and the voltage or resistance output terminal can become a resistance output terminal or a voltage output terminal according to the output signal. The output terminal 6 is connected to the input terminal group 7 correspondingly, which means that when the output terminal 6 is the current output terminal, the current output terminal is connected with the current input terminal 9; when the output terminal 6 is the voltage output terminal, the voltage output terminal is connected with the voltage input terminal. The terminals are connected; when the output terminal 6 is the resistance output terminal, the resistance output terminal is connected with the resistance input terminal.

The wiring base 2 is provided with six meter positions 12 for fixing the digital multimeter, and each meter position 12 is provided with a connection end connected with the input terminal group 7, and the connection end is connected with the digital multimeter, which can be realized through a Standard source 1 calibrates and acquires data from six digital multimeters.

Further, the input terminal group 7 also includes a micro-current input terminal 10. The micro-current input terminal 10 is connected to the connection end, the connection end is connected to the output end, and a current protection module 11 is arranged between the output end and the connection end. When the input current of the micro-current input terminal 10 is greater than the specified value, the current loop will be automatically cut off to protect the digital multimeter. The function of the current protection module 11 is similar to that of a fuse, and will not be repeated here.

The area where the camera 3 collects images is the collection area, and the collection area covers the six epitopes 12 , and the data of six digital multimeters can be collected at a time through the camera 3 . Also, because the collection area is covered on the six epitopes 12 , the camera 3 can collect the indication image more accurately.

As shown in FIG. 2 , as the first embodiment of the present invention, when the voltage signal of the digital multimeter needs to be collected, the voltage or resistance input terminal 8 becomes the voltage input terminal. Under the control of the output control module 4, the voltage output terminal in the standard source 1 outputs a voltage signal to the voltage input terminal, and the output voltage signal is a standard voltage signal, and the voltage signal is simultaneously provided to six digital multimeters through a parallel circuit. After the multi-function indicator is stable, the camera 3 collects the indicator images one by one, and then the image recognition module 5 recognizes the indicator images and reads and records the indicator.

As shown in FIG. 2 , as the second embodiment of the present invention, when the resistance signal of the digital multimeter needs to be collected, the voltage or resistance input terminal 8 becomes the resistance input terminal. Under the control of the output control module 4, the resistance output terminal in the standard source 1 outputs a voltage signal to the resistance input terminal, and the resistance signal is sequentially supplied to six digital multimeters through a parallel circuit. After the digital multimeter is stable, the camera 3 The indication images are collected one by one, and then the image recognition module 5 identifies the indication images and reads the recorded indications.

As shown in Figure 3, as the third embodiment of the present invention, when the current signal of the digital multimeter needs to be collected, the current output terminal in the standard source 1 outputs the current signal to the current input terminal 9, and the output current signal is Standard current signal, the current signal is simultaneously provided to six digital multimeters through the series circuit. After the digital multimeter is stable, the camera 3 will collect the indication images one by one, and then the image recognition module 5 will identify the indication image and read and record the indication. .

In the present invention, the signal output of the standard source 1 is controlled by the output control module 4, that is, the signal output from the standard source 1 can be intelligently controlled by the output control module 4 to be a voltage signal, a resistance signal or a current signal, or the output control module 4. Control the size of the output signal of the standard source 1, and realize the intelligent control of the output of the standard source 1. After the camera 3 collects the indication images of multiple digital multimeters, the image recognition module 5 can identify the data in the indication images and record the data, thereby realizing the effect of data collection and improving the calibration efficiency.

Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Claims (9)

1. an automatic calibration system of a digital multimeter, is characterized in that, comprises standard source, wiring base, camera head, output control module and image recognition module; Described standard source is used for outputting voltage, resistance or current signal, and respectively with The output control module is connected with the wiring base; the output control module is used to control the output signal of the standard source; the wiring base can place multiple digital multimeters; the camera is connected to the image recognition module connected, the camera is used for collecting the indication image of the digital multimeter, and the image recognition module is used for recognizing the indication image and reading and recording the indication. 2. The automatic calibration system of a digital multimeter according to claim 1, wherein an output terminal is provided on the standard source; an input terminal group is provided on the wiring base, and the output terminal and the input terminal are provided with groups are connected. 3. The automatic calibration system of a digital multimeter according to claim 2, wherein the output terminal comprises a voltage or resistance output terminal and a current output terminal; the input terminal group comprises a voltage input terminal, a resistance input terminal and a current input terminal, the output terminal is correspondingly connected with the input terminal. 4. The automatic calibration system of a digital multimeter according to claim 2, wherein the wiring base is provided with six table positions for fixing the digital multimeter, and each table position is provided with the The connection end connected with the input terminal group is connected with the digital multimeter. 5. The automatic calibration system of a digital multimeter according to claim 4, wherein the input terminal group further comprises a micro-current input terminal, the micro-current input terminal is connected with the connection end, and the micro-current input terminal is connected with the connection end. The output ends are connected; a current protection module is arranged between the connection end and the output end. 6 . The automatic calibration system for a digital multimeter according to claim 5 , wherein the area where the camera collects images is a collection area, and the collection area covers the six epitopes. 7 . 7. The automatic calibration system of a digital multimeter according to claim 1, wherein the standard source is a FLUKE5522A calibrator. 8. The automatic calibration system of a digital multimeter according to claim 1, wherein the digital multimeter is a FLUKE179 type digital multimeter. 9 . The automatic calibration system for a digital multimeter according to claim 1 , wherein the camera is an HF900 wide dynamic industrial camera. 10 .

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