CN213813788U

CN213813788U - Induction type three-phase alternating current phase sequence measurement intelligent digital multimeter

Info

Publication number: CN213813788U
Application number: CN202023001755.3U
Authority: CN
Inventors: 张健
Original assignee: Shenzhen Hanyan Tech Co ltd
Current assignee: Shenzhen Hanyan Tech Co ltd
Priority date: 2020-12-14
Filing date: 2020-12-14
Publication date: 2021-07-27
Anticipated expiration: 2030-12-14

Abstract

The utility model relates to a technical field is measured to the phase sequence, discloses an intelligent digital multimeter is measured to induction type three-phase alternating current phase sequence, including AD conversion chip and respectively with the electrical power generating system, decay circuit, magnetism that AD conversion chip electricity is connected, operational amplifier, integrator, button, LCD drive circuit, liquid crystal display and test needle, AD conversion chip has signal input port VR, the test needle is connected with signal input port VR electricity, electrical power generating system with the VDD and the VSS pin electricity of AD conversion chip are connected, electrical power generating system and operational amplifier and integrator series connection, and liquid crystal display is connected with LCD drive circuit electricity, and the decay circuit keeps the conversion circuit electricity with magnetism to be connected. The technical scheme of the utility model can show current measuring phase sequence ABC value through liquid crystal display in real time, and is more directly perceived, and it is more convenient to read, makes original complicated phase sequence measurement become simple, directly perceived, swift, and the practicality is strong.

Description

Induction type three-phase alternating current phase sequence measurement intelligent digital multimeter

Technical Field

The utility model relates to a phase sequence measures technical field, in particular to induction type three-phase alternating current phase sequence measures intelligent digital multimeter.

Background

The phase sequence refers to the sequence of three-phase alternating-current voltage, and is the sequence of alternating-current instantaneous value changing from negative value to positive value and passing through zero value, three conductors are arranged in an alternating-current power system and are divided into ABC three phases, the three-phase voltage and the current are symmetrical under the normal condition, the phase difference is 120 degrees, and in the three-phase alternating-current power system, whether the phase sequence and the phase position of a generator, a transformer and the like are consistent or not is directly related to whether the three-phase alternating-current voltage and the three-phase alternating-current voltage can run in parallel or not. Meanwhile, the positive and negative phase sequences also directly influence the rotation direction of the motor, and the phase sequence of the equipment in use cannot be reversed, so that the operation procedure of the equipment can be changed, and sometimes the equipment is dangerous, so that in a three-phase power system, the phase sequence and the phase of the equipment are often required to be measured to determine the operation mode of the equipment.

However, most of the existing phase sequence measuring devices are cumbersome to operate, inefficient, and unable to visually display specific phase sequence values, and further improvement is needed.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an induction type three-phase alternating current phase sequence measures intelligent digital multimeter aims at solving current phase sequence measuring device complex operation, and is inefficient, and the technical problem that can not audio-visually show specific phase sequence value.

In order to realize the above-mentioned purpose, the utility model provides an induction type three-phase alternating current phase sequence measures intelligent digital multimeter, including AD conversion chip and respectively with electrical power generating system, decay circuit, magnetic latching converting circuit, operational amplifier, integrator, button, LCD drive circuit, liquid crystal display and the test needle that AD conversion chip electricity is connected, AD conversion chip has signal input port VR, the test needle with signal input port VR electricity is connected, electrical power generating system with the VDD and the VSS pin electricity of AD conversion chip are connected, electrical power generating system with operational amplifier and integrator series connection, liquid crystal display with LCD drive circuit electricity is connected, decay circuit with the magnetic latching converting circuit electricity is connected.

Further, the A/D conversion chip adopts an SD7501 chip.

Further, the operational amplifier adopts an AD8541 chip.

Further, the integrator employs an a42S4 chip.

Adopt the technical scheme of the utility model, following beneficial effect has: the technical scheme of the utility model, through AD conversion chip respectively with electrical power generating system, decay circuit, magnetic latching conversion circuit, operational amplifier, integrator, button, LCD drive circuit, liquid crystal display and test needle, AD conversion chip has signal input port VR, the test needle with signal input port VR electricity is connected, electrical power generating system with VDD and VSS pin electricity of AD conversion chip are connected, electrical power generating system with operational amplifier and integrator series connection, liquid crystal display with LCD drive circuit electricity is connected, decay circuit with magnetic latching conversion circuit electricity is connected, can show current measuring phase sequence ABC value through liquid crystal display in real time, and is more directly perceived clear, and it is more convenient to read, makes original complicated phase sequence measurement become simple, directly perceived, The method is fast and practical.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a connection diagram of an overall frame of an inductive three-phase ac phase sequence measurement intelligent digital multimeter according to an embodiment of the present invention;

fig. 2 is an overall circuit schematic diagram of an inductive three-phase ac phase sequence measurement intelligent digital multimeter according to an embodiment of the present invention;

fig. 3 is a schematic circuit diagram of a power supply system of an inductive three-phase ac phase sequence measurement intelligent digital multimeter according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a phase sequence conversion circuit of the inductive three-phase ac phase sequence measurement intelligent digital multimeter according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a signal input conversion circuit of the inductive three-phase ac phase sequence measurement intelligent digital multimeter according to an embodiment of the present invention.

The purpose of the present invention is to provide a novel and improved method and apparatus for operating a computer.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The utility model provides an induction type three-phase alternating current phase sequence measures intelligent digital multimeter.

As shown in fig. 1 to fig. 2, in an embodiment of the present invention, the induction type three-phase ac phase sequence measurement intelligent digital multimeter comprises an a/D conversion chip 101, and a power system 102, an attenuation circuit 103, a magnetic latching conversion circuit 104, an operational amplifier 105, an integrator 106, a key 107, an LCD driving circuit 108, an LCD 109 and a testing pin 110 electrically connected to the a/D conversion chip 101, the A/D conversion chip 101 has a signal input port VR, the test pin 110 is electrically connected to the signal input port VR, the power system 102 is electrically connected to the VDD and VSS pins of the a/D conversion chip 101, the power supply system 102 is connected in series with the operational amplifier 105 and the integrator 106, the liquid crystal display screen 109 is electrically connected to the LCD driving circuit 108, and the attenuation circuit 103 is electrically connected to the magnetic latching conversion circuit 104.

Specifically, the a/D conversion chip 101 employs an SD7501 chip.

Specifically, the operational amplifier 105 employs an AD8541 chip.

Specifically, the integrator 106 employs an a42S4 chip.

Specifically, the utility model discloses a phase sequence measurement principle and process are: contacting a test needle of the digital multimeter with a phase line to be tested, enabling a sine input signal to enter A2 after being switched by VR through PTC1 and a magnetic latching relay of a magnetic latching conversion circuit, outputting the sine input signal through an A3 port after internal conversion, outputting a square wave signal through an integrator after being switched by an operational amplifier IC4 (serving as a follower to provide input impedance), outputting the square wave signal through the integrator, capturing the maximum value of the rising edge of the square wave and recording the current time when a first phase line is tested according to the phase sequence difference of three phase lines ABC, capturing the current maximum value when a second phase line is tested and recording the current time because the signal is already changed into the square wave signal after being compared by an operational amplifier AD8541 chip and an integrator A42S4 chip, wherein the first phase line leads the second phase line by 120 degrees and the second phase line leads the third phase line by 120 degrees according to the principle that the phase lines differ by 120 degrees, the time between the phase lines is different, the phase sequence of the first phase line, the second phase line and the third phase line can be distinguished according to the time difference as long as three phase lines are respectively measured in a short time, and the currently measured phase sequence ABC value is displayed through the liquid crystal display screen in real time.

The above only be the preferred embodiment of the utility model discloses a not consequently restriction the utility model discloses a patent range, all are in the utility model discloses a conceive, utilize the equivalent structure transform of what the content was done in the description and the attached drawing, or direct/indirect application all is included in other relevant technical field the utility model discloses a patent protection within range.

Claims

1. The intelligent digital multimeter is characterized by comprising an A/D conversion chip, a power supply system, an attenuation circuit, a magnetic latching conversion circuit, an operational amplifier, an integrator, a key, an LCD (liquid crystal display) driving circuit, a liquid crystal display screen and a test pin, wherein the power supply system, the attenuation circuit, the magnetic latching conversion circuit, the operational amplifier, the integrator, the key, the LCD driving circuit, the liquid crystal display screen and the test pin are respectively electrically connected with the A/D conversion chip, the A/D conversion chip is provided with a signal input port VR, the test pin is electrically connected with the signal input port VR, the power supply system is electrically connected with VDD and VSS pins of the A/D conversion chip, the power supply system is connected with the operational amplifier and the integrator in series, the liquid crystal display screen is electrically connected with the LCD driving circuit, and the attenuation circuit is electrically connected with the magnetic latching conversion circuit.

2. The induction type intelligent digital multimeter for measuring the phase sequence of the three-phase alternating current according to claim 1, wherein the A/D conversion chip is an SD7501 chip.

3. The inductive three-phase alternating current phase sequence measurement intelligent digital multimeter of claim 1, wherein the operational amplifier employs an AD8541 chip.

4. The inductive three-phase alternating current phase-sequence measuring intelligent digital multimeter of claim 1, wherein the integrator employs an a42S4 chip.