Portable programmable high-precision anti-interference high-voltage resistance voltage sampling box

Abstract

The utility model discloses a portable programmable high-precision anti-interference high pressure voltage division sampling box, including input, control unit, direct connection loop, voltage division loop, output sampling end, built -in programmable controller and high -precision signal relay, realize the complete automation of testing process, adopt full metal shell to carry out electromagnetic shielding, and combine high -precision voltage division resistor design, support the high voltage test range from DC1000V to DC2500V, through the high voltage reed relay of adding the isolation high voltage and low pressure, has further improved the voltage grade of system. The utility model can adapt to most digital multimeter, and the interference killing ability is strong, and the resistance value is stable, improves the voltage grade of ordinary digital multimeter, and greatly improves the test efficiency and accuracy.

Description

TECHNICAL FIELD

[0001] The utility model relates to power supply test technical field especially relates to a portable programmable high-precision anti -interference high -voltage resistance partial pressure sampling box. BACKGROUND

[0002] In the field of power electronics and precision instruments, the calibration and testing of high-precision programmable power supply is the key link to ensure that the performance indicators of the equipment meet the design requirements. Currently, when calibrating and testing high-precision power supply in the industry, high-precision multimeter is needed for output voltage testing, and high-precision multimeter is also needed for output current testing in cooperation with shunt resistor. However, the existing technical solutions have the following significant defects:

[0003] 1. The conventional digital multimeter is subject to input protection circuit and range design, and the upper limit of direct current voltage measurement is usually DC 1000V, and the upper limit of alternating current voltage measurement is AC 750V. For ultra-high voltage equipment, a mega-ohm partial pressure resistor needs to be externally connected, but such high resistance devices are extremely sensitive to space electromagnetic interference, resulting in random jitter of the sampled voltage, which seriously affects the measurement accuracy.

[0004] 2. When testing the current, the multimeter needs to read the sampling voltage on the shunt resistor, and the voltage level is usually not high, so the partial pressure resistor during voltage testing needs to be removed, otherwise the partial pressure resistor value is large and is easily disturbed, resulting in jitter of the read current sampling voltage value.

[0005] 3. The input ports of digital multimeters produced by different manufacturers differ in mechanical structure, plug-in method and signal definition. In order to quickly and reliably plug the partial pressure resistor into the input port, different sampling harnesses need to be made for products of different manufacturers, which also increases the inconvenience of preparing test equipment.

[0006] The multiple defects of the existing technical solutions in terms of testing accuracy, operation efficiency and system compatibility have become a bottleneck problem restricting the improvement of high-precision power supply equipment testing efficiency, and a new integrated testing solution is urgently needed to overcome the above technical obstacles. INVENTION CONTENTS

[0007] The utility model aims at providing a portable programmable high-precision anti-interference high-voltage resistance partial pressure sampling box to solve the problems raised in the above background technology.

[0008] To solve the above technical problems, the utility model provides the following technical scheme:

[0009] The utility model provides a portable programmable high-precision anti-interference high-voltage voltage division sampling box, comprising: an input end for connecting a device under test; a control unit coupled to the input end for switching a direct connection circuit and a voltage division circuit to achieve gear shifting; a direct connection circuit coupled between the control unit and an output sampling end for directly transmitting a signal under test when voltage division is not required; a voltage division circuit coupled between the control unit and the output sampling end, including a high-precision voltage division resistor for voltage division sampling of a high-voltage signal; and an output sampling end for connecting a test device to read the sampled signal.

[0010] Further, the control unit includes a high-precision signal relay and a programmable controller that automatically switches gears according to instructions from an upper computer.

[0011] Further, it also includes a high-voltage reed relay for isolating high and low voltages to improve the voltage rating of the system.

[0012] Further, it includes a Teflon gasket and plastic screws for improving insulation levels.

[0013] Further, the shell is made of all-metal material for electromagnetic shielding of internal components.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] 1. The utility model is designed with exquisite design, which can adapt to most desktop digital multimeters in the industry, greatly widening its application scenarios and flexibility, and providing great convenience for users.

[0016] 2. By using an all-metal shell to electromagnetically shield internal components and a high-precision voltage division resistor design, the utility model exhibits strong anti-interference ability, stable resistance, and is not affected by spatial electromagnetic interference, ensuring the accuracy and reliability of test results.

[0017] 3. The utility model not only supports testing in the conventional voltage range, but also increases the test voltage level from DC1000V to DC2500V, meeting the urgent needs of the high-voltage testing field and widening the use of digital multimeters.

[0018] 4. The built-in programmable controller combined with the high-precision signal relay realizes complete automation of the testing process, allowing users to flexibly switch gears through instructions from an upper computer, greatly improving testing efficiency and accuracy.

[0019] 5. The voltage division resistor has a voltage division proportionality coefficient error of less than or equal to 100ppm, ensuring high precision of the sampled voltage and providing accurate and reliable test data support for scientific research, industrial production, and other fields.

[0020] 6. This utility model fully considers the complex environment of industrial sites in its communication design, ensuring the reliability and stability of communication, and maintaining a stable communication connection even in harsh industrial sites. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them:

[0022] Figure 1 This is a schematic diagram of the sampling box frame.

[0023] Figure 2 This is a schematic diagram of the internal structure of the sampling box.

[0024] Explanation of reference numerals in the attached diagram: 1. Input terminal; 2. Output sampling terminal; 3. Control unit; 31. Signal relay; 32. High-voltage reed relay; 4. Power supply and USB communication module; 5. PCB board. Detailed Implementation

[0025] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the examples in the specification.

[0026] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] like Figure 1 , Figure 2 As shown, this utility model discloses a portable programmable high-precision anti-interference and high-voltage-resistant voltage divider sampling box, including an input terminal 1, a control unit 3, a direct-connection circuit, a voltage divider circuit, and an output sampling terminal 2, as well as a power supply and USB communication module 4 and a PCB board 5. The input terminal 1 is coupled to the control unit 3, the control unit 3 is coupled to the direct-connection circuit and the voltage divider circuit, the direct-connection circuit and the voltage divider circuit are coupled to the output sampling terminal 2, the control unit 3 is also sequentially coupled to an ARM controller, and the power supply and USB communication module 4 includes USB communication and a power supply for power supply.

[0028] Input terminal 1: Used to connect the positive and negative terminals of the device under test;

[0029] The control unit 3 is used for switching the direct connection circuit and the voltage division circuit, and realizes gear switching. Specifically, it includes a high-precision signal relay, which is used for sampling and switching the sampling signal and is programmably controlled by an ARM controller. The program controls the automatic switching of the gear. When receiving the instruction "HIGH VOLTAGE" sent by the upper computer, the high-voltage gear is switched. When receiving the instruction "LOW VOLTAGE" sent by the upper computer, the low-voltage gear is switched. The lower computer control board based on the STM32F103 chip and the upper computer maintenance software respond to the control instructions of the upper computer through the lower computer firmware program, check whether the control is correct, and can also detect whether the relay is correctly actuated after sending the control instruction. The STM32 series MCU is used to realize programmable operation, and can communicate with the upper computer and save the resistance coefficient through USB communication.

[0030] The direct connection circuit is used for directly transmitting the signal to be measured to the output sampling end 2 without voltage division. The direct connection circuit adopts a low-impedance design to minimize the loss in the signal transmission process, and is suitable for low-voltage gear measurement.

[0031] The voltage division circuit includes a voltage division resistor, which includes two groups of fixed voltage division ratio resistor configurations: 20MΩ:20KΩ and 20MΩ:40KΩ, and is used for sampling high voltage. A high-precision voltage division resistor is used, and the voltage division ratio coefficient error of the voltage division resistor is less than 0.01%. The voltage division resistor coefficient can be saved and read. When the voltage division resistor needs to be used, the high-voltage gear of the voltage division circuit is switched. When voltage division is not needed, the direct connection circuit is switched to directly connect to the multimeter to realize direct connection of the low-voltage gear.

[0032] The output sampling end 2 can be directly inserted into the input port of the multimeter for use, which is convenient and suitable for most desktop digital multimeters in the industry.

[0033] The embodiment also improves the high-voltage resistance, insulation level, and anti-interference. More specifically, a high-voltage reed relay is used in the embodiment to isolate high voltage and low voltage, resist high voltage, and resist voltage up to DC 2500V, which can test most power supplies in the industry.

[0034] At the same time, a slot is arranged on the PCB 5, specifically, the slot width is greater than or equal to 0.762mm, and the depth completely penetrates the PCB substrate, which improves the voltage resistance between the pins of components and improves the overall voltage resistance. The overall volume can be compressed to a minimum. In the embodiment, the volume is 83*38*40mm, which does not occupy too much space in the test system.

[0035] Use Teflon gasket, improve the output terminal and the shell between the insulation level. Use plastic screws and plastic pad high column to improve the internal insulation level. Double insulation of Teflon gasket and plastic screw can ensure the safety use under DC2500V. The full metal shell is electromagnetic shield to the internal voltage dividing resistor, so that the voltage jitter of the voltage dividing resistor sampling is less than 10ppm, and the anti-interference ability is strong.

[0036] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced by equivalent, without departing from the spirit and scope of the technical solutions of the present application, which should be covered in the scope of the claims of the present application.

Claims

1. A portable programmable high-precision anti-interference high-voltage resistance voltage division sampling box, characterized in that, The application relates to a high-voltage signal sampling device, which comprises the following parts: an input end for connecting a device to be tested; a control unit coupled to the input end, used for switching a direct connection circuit and a voltage division circuit to realize gear switching; a direct connection circuit coupled between the control unit and an output sampling end, used for directly transmitting a signal to be tested when voltage division is not needed; a voltage division circuit coupled between the control unit and the output sampling end, comprising a high-precision voltage division resistor, used for voltage division sampling of a high-voltage signal; an output sampling end used for connecting a testing device to read a sampling signal.

2. The portable programmable high-precision anti-interference high-voltage dividing sampling box according to claim 1, characterized in that, The control unit comprises a high-precision signal relay and a programmable controller, and the programmable controller automatically switches gears according to an instruction of an upper computer.

3. The portable programmable high-precision anti-interference high-voltage dividing sampling box according to claim 1, characterized in that, A high-voltage dry reed relay is further arranged for isolating high voltage and low voltage, so that the voltage resistance level of the system is improved.

4. The portable programmable high-precision anti-interference high-voltage dividing sampling box according to claim 1, characterized in that, A Teflon gasket and a plastic screw are further arranged for improving insulation level.

5. The portable programmable high-precision anti-interference high-voltage dividing sampling box according to claim 1, characterized in that, The shell is made of full metal material, and is used for electromagnetic shielding of internal elements.

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